• 기계와재료
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• v.22 no.3
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• pp.110-119
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• 2010

인공아가미기술은 수중에서 용존산소를 분리하여 호흡에 사용하는 것을 말한다. 이를 위해 아가미의 특성을 분석하고 현재까지 제시되고 있는 용존산소의 분리를 위한 메커니즘 특성을 기술하였다. 즉 압력 강하, 캐리어 용액, plastron의 관점에서 용존산소를 분리하여 수중 호흡에 사용하는 부분에 대해 소개하였다. 또한, 현재 진행 중인 용존산소 분리실험장치를 이용한 수중 용존산소의 감소특성을 제시하였다. 압력을 감소함에 따라 용존산소량이 비례하여 감소함을 알 수 있었다. 중공사막에 공급되는 유량을 증가시키면 용존산소량의 감소가 둔화되는 특성을 나타낸다. 휴대형 인공아가미기술은 물놀이와 관련된 레저활동의 안전도구로 활용이 가능하고, 스쿠버다이버, 마이크로연료전지, 인공부레, 잠수함 그리고 인공 폐 분야에 사용이 기대된다.

• Journal of the Korean Society of Marine Environment & Safety
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• v.16 no.4
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• pp.339-344
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• 2010

Oxygen depleted water mass can damage aquatic animals not only in direct way but also in indirect way by generating toxic substances including occurrence of hydrogen sulfide and ammonia which are also highly detrimental to animal life in the water mass. An oxygen dissolution device was developed, which makes turnover of the oxygen rich (over 20 mg/L) surface water down to the bottom where hypoxia is evident and tested the device in terms of oxygen recovery in the oxygen depleted bottom water. the device with turnover rates of $3.6\;m^2$/min at the liquid oxygen injection rate of 48~26.3 L/min could recover dissolved oxygen level to 7~25 mg/L at depth 7 m to lead to the dissolution level of over 90% by the supply of liquid oxygen. The running advantage of the device is that it does not require any auxiliary tank and higher energy for operation. Therefore, it can be highly useful device to relieve damages to the farmed animals in the oxygen depleted waters.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.676-677
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• 2010

In Naro Space Center, Naro launch vehicle launched 2 times. Launch pad for Naro launch vehicle in Naro space center equipped propellant feeding facility for operating launch process. This paper studied development process and operating method for liquid oxygen filling system of cryogenic propellant systems in launch pad propellant feeding facility.

• KSBB Journal
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• v.23 no.6
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• pp.551-553
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• 2008

In order to optimization germination condition of broccoli, we carried out germination ratio experiment under soaking time, soaking temperature, oxygen concentration. The germination ratio results 98.5% following as soaking water having 10 ppm DO(demanded oxygen) during 4 hr at $20{\sim}30^{\circ}C$. The result of provide the dissolved oxygen water, when the concentration of oxygen water were 7, 12 ppm, germination ratio were observed about 76%, 92%. Also, we showed the growth rate of 2 times in 12 ppm compared with 7 ppm. Consequently, germination ratio of broccoli increased cultivation condition at soaking water having high concentration oxygen more than supply to oxygen water of high concentration.

• Proceedings of the Membrane Society of Korea Conference
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• 1994.04a
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• pp.13-18
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• 1994

99.9% 이상의 고순도 산소를 대량으로 생산하기 위하여는 주로 냉동 증류(cryogenic fractionation)가 사용된다[1]. 그러나 의료 분야를 비롯하여 소량의 산소를 필요로 하는 많은 분야에서 요구되는 산소의 순도는 40-90% 범위에 있다[2,3]. 이 정도 등급의 산소의 공급은 PSA(Pressure Swing Adsorption)과 MP(Membrane Permeation)의 공정에 의존하게 될 가능성이 크다[4,6]. 이는 이 공정들이 작은 규모의 생산에 적합할 뿐만 아니라 조업이 용이하고, 유지비가 적게 들며 장치의 재배치가 용이하기 때문이다.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.239-240
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• 2000

용존산소는 양식 시설 내 생산량을 결정짓는 중요한 수질 조건으로서, 시설 내 용존산소를 충분히 공급하기 위해 많은 연구자들이 여러 가지 형태의 에어레이터의 고안(Boyd and Tucker, 1979)및 순수산소의 이용에 관해 연구해왔다. 그러나 에어레이터 또는 순수 산소의 이용은 추가 에너지가 필요한데, 송어 양식장에는 전체비용의 13∼15%, 부화장의 경우에는 23%(Petit, 1990) 및 순환여과식 시설에서는 8.6%(Timmons and Aho, 1998)의 경비가 추가된다고 한다. (중략)

• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.4
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• pp.1022-1032
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• 1990

본 연구에서는 기체연료 연소시 산소부화연소의 적용에 대한 연구를 시작하는 단계에서 상용 프로판을 산소부화연소 시킴으로써 첨가된 산소에 의한 반응시간의 단 축과 공급 공기량중의 질소량 저감에 희한 연소가스중의 NO농도를 측정하고, 이에 따 른 화염장의 온도 및 연소가스중의 $O_{2}$ 및 N$_{2}$농도를 측정하여 그들의 상관관 계를 가지고 NO의 배출특성을 고찰함으로써 기체연료의 산소부화연소에 따른 효율적인 에너지 이용을 위한 연소장치개발과 오염물질 저감대책에 기초자료를 제공하는데 그 목적이 있다.

• Journal of Biomedical Engineering Research
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• v.24 no.4
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• pp.267-273
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• 2003

The present study attempted to observe what changes the supply of highly concentrated (30%) oxygen cause to people's ability of visuospatial cognition, compared to air of normal oxygen concentration (21%). This study sampled eight male university students (the average age : 23.5) as subjects for functional Magnetic Resonance Imaging (MRI) study It also developed equipment that supplies 21% and 30% oxygen) at a constant rate of 8L/min. Two questionnaires containing 20 questions were developed to measure the ability of visuospatial cognition, and accuracy was calculated from the result of task performance. The experiment paradigm consisted of the run conducting tasks at 30%'s concentration of oxygen and another run at 21%'s concentration of oxygen. Each run was composed of four blocks and each block included eight control tasks and five visuospatial taks. 3T MRI was used and fMRI was obtained through the single-shot EPI method. The activation in the occipital-associated area, bilateral superior parietal lobes, bilateral inferior parietal lobes. bilateral precuneus, bilateral postcentral gyri, bilateral middle frontal gyri, bilateral inferior frontal gyri, bilateral medial frontal gyri, bilateral superior frontal gyri, bilateral cingulate gyri was significantly increased at the 30%'s concentration of oxygen rather than 21%'s. Furthermore, the result of task performance showed the accuracy increased at 30%'s concentration of oxygen rather than 21%'s. From the result of this study, it is concluded that the supply of highly concentrated oxygen has a positive effect on the ability of visuospatial cognition.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.11a
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• pp.122-126
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• 2006

Two types of pressurization system and low weight feeding piping system are developed. With sub-system tests, ullage pressure control performance was verified for 1 step and 2 step pressurization system and the feeding performance of feeding piping system was also verified. The weight of the feeding piping system is low enough for the application of launch vehicle. In addition, LOX conditioning system is developed for avoiding geysering and LOX temperature rise. Integrated performance was verified through integrated on-board feeding system performance tests.

• KSBB Journal
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• v.5 no.3
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• pp.307-313
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• 1990

A microcomputer-aided fermentation system was constructed for high density fed-batch culture using dissolved oxygen(DO) as a substrate feeding indicator. DO signal was processed prior to aquisition to computer. Agitation speed and oxygen flow rate was changed stepwisely to maintain DO value at a constant level. Agitation speed was controlled by the output signal of D/A converter. Oxygen flow rate was controlled by a flow rate control valve connected to a stepping motor. Substrate was fed with a feeding pump operated by the abrupt increase of DO signal. Methylobacillus sp. SK1 was cultivated to test the system and 16.53g/l of cell density was obtained after 10 hr.