• Korean Journal of Fisheries and Aquatic Sciences
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• v.24 no.5
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• pp.303-314
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• 1991

Hypoxic bottom $(\leq2.0ml/l),\;40\%\;oxygen\;saturation)$ is formed in the semi-closed Wonmun bay during summer and autumn early. This study was carried out to know seasonal distribution of marine bacteria and the role of marine bacteria for forming the hypoxic bottom at Wonmun bay during summer and autumn early, 1990. During the study periods, 170 bacterial strains were isolated from sea water and sediment. Viable cell counts were ranged between $10^5-10^7\;cells/ml$. The dominant species were Acinetobacter spp. in spring, Flavobacerium spp. in summer, Pseudomonas spp. in autumn, Serratia spp. in winter. Because ETSA(Electron Transport System Activity) reveals potential consumption of oxygen in the aquatic microorganisms, the ETSA was used as potential consumption of oxygen in this study. The potential consumption of oxygen was in the range of $232.4-637.5{\mu}l/O_2/l/day$ by marine organism and $142.6-432.4{\mu}l/O_2/l/day$ by marine bacteria during the study periods. The ratio of potential oxygen consumption of marine bacteria to total marine microorganism was 0.54. The potential consumption of oxygen by marine bacteria closely related with the number of viable cells. Consequently, bacteria play an important role to form Hypoxic bottom at marine environment.

• Journal of the Korea Convergence Society
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• v.9 no.11
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• pp.363-369
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• 2018

The purpose of this study was to investigate the differences of lumbar muscle activity (LMA) and oxygen consumption (OC) according to bike saddle height in healthy young men. Twenty-two subjects without musculoskeletal disorders participated in this study. Subjects performed 3 min cycling at 3 different saddle heights with 10 minutes of resting time respectively. Surface EMG was used to assess muscle activity in LMA, and OC was assessed by potable gas analyzer. In the result, there was a statistically significant difference in internal oblique abdominis activity (p<0.05), and the OC was significantly higher in high saddle height than the optimal and the low position of the saddle (p<0.05). This study suggest that changes in saddle height affected internal oblique abdominis activity and OC in subjects, however, saddle height does not have much effect on lumbar stabilizer muscle.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2013.11a
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• pp.49-49
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• 2013

실규모급 화재 실험의 신뢰성 있는 발열량 측정을 위해서 흡입 배관의 직경 1.6 m, 직선길이 26m, 후드 직경 10 m 그리고 흡입용량 $2,000m^3/min$ 이상의 대형 콘 칼로리미터를 구성하여 헵탄의 화재 크기별 연소 실험을 진행하였다. 발열량 측정을 비교 분석하기 위해서 산소 소모 지수법, 질량 소모법, 복사열 그리고 대류열 측정 기법에 따라서 각각의 발열량을 산출하고 크기를 비교하였다. 그 결과 대형 콘 칼로리미터에 의해서 측정한 산소 소모 지수법은 이론 발열량에 해당하는 질량 소모법과 최대 약 2.3 % 정도, 복사열에 의한 발열량 산출법은 12.2 % 정도, 연소면적에 의한 이상적인 발열량과는 최대 30 % 정도, 그리고 대류열만 고려한 경우 약 50 % 정도 차이가 나는 것을 확인하였다.

• Korean Journal of Environment and Ecology
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• v.33 no.5
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• pp.596-604
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• 2019

This study conducted a sediment culture experiment to investigate the effects of sediment oxygen demand (SOD) and environmental factors on sediment and water quality. We installed a leaching tank in the laboratory, cultured it for 20 days, and analyzed the relationship between P and Fe in the sediment. As a result, the dissolved oxygen of the water layer decreased with time, while the oxidation-reduction potential of the sediment progressed in the negative direction to form an anaerobic reducing environment. The SOD was measured to be 0.05 mg/g at the initial stage of cultivation and increased to 0.09 mg/g on the 20th day, indicating the tendency of increasing consumption of oxygen by the sediment. The change is likely to have caused by oxygen consumption from biological-SOD, which is the decomposition of organic matter accumulated on the sediment surface due to the increase of chl-a, and chemical-SOD consumed when the metal-reducing product produced by the reduction reaction is reoxidized. The correlation between SOD and causality for sediment-extracted sediments was positive for Ex-P and Org-P and negative for Fe-P. The analysis of the microbial community in the sediment on the 20th day showed that anaerobic iron-reducing bacteria (FeRB) were the dominant species. Therefore, when the phosphate bonded to the iron oxide is separated by the reduction reaction, the phosphate is eluted into the water to increase the primary productivity. The reduced substance is reoxidized and contributes to the oxygen consumption of the sediment. The results of this study would be useful as the reference information to improve oxygen resin.

• Analytical Science and Technology
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• v.26 no.6
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• pp.401-406
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• 2013

Oxygen($O_2$) consumption and carbon dioxide($CO_2$) excretion of a fertile chicken egg during incubation were measured by a gas mass spectrometer. A closed sample chamber was developed to collect gas samples during the 20 days of artificial incubation of both a fertile and an infertile egg. After leaving an egg in the sample chamber for an hour, using a gas-tight syringe, samples of 2 mL of gas were collected from the closed sample chamber and analyzed using a gas mass spectrometer in 2~4 day intervals. The $O_2$ consumption and $CO_2$ excretion of chicken embryos increased rapidly after 10 days from the starting point of incubation. After 20 days, 23 mL of $O_2$ was consumed and 16 mL of $CO_2$ was excreted per hour. Throughout the whole period of incubation, concentration of $O_2$ decreased 4.3 mol% and $CO_2$ increased only 3.1 mole%, i.e., the mole of consumed $O_2$ and the mole of excreted $CO_2$ were not the same. On the other hand, during the same period, concentration of $N_2$ increased about 1.3 mol% and the increased mole fraction of $N_2$ was comparable with the difference (1.2 mol%) between the mole fraction of consumed $O_2$ and excreted $CO_2$. Therefore, we can attribute the increase of $N_2$ mole% to the difference of mole fraction between consumed $O_2$ and excreted $CO_2$. In this study, through the analysis of gas, we could explain the respiration of a fertile chicken egg during incubation.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2008.04a
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• pp.303-307
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• 2008

In this study, we have carried out the cone calorimeter test to examine the thermal characteristics, such as total smoke production(TSP), smoke temperature and oxygen consumption, of significant parts of above trees which are representative species of Young Dong Province of Korea. The smoke production of dead leaves and living leaves of pinus densiflora was increased rapidly at the early period of combustion. So the total smoke production of this parts was 8.3 times higher than other parts. The TSP of branches and barks of quercus dentata was 14.4 and 7.2 times higher than of pinus densiflora respectively. And also the maximum smoke temperature was about $338.35{\sim}353.25\;K$. The significant difference of oxygen consumption was not detected for dead leaves, branches and barks. However, the oxygen consumption of living leaves which have high percentage of moisture content is the lowest.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.656-657
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• 2010

The ground oxidizer supply system in the launch site of NARO space center had operated 9 times from the start of tests with ILV on May, 2009 to the 2nd flight test of the NARO vehicle. This system operated successfully for twice launches of the NARO vehicle. To judge the successful operation of the ground facility, it should have reproducibility and reliability. In this report, we have analyzed the liquid oxygen consumption of the system to judge of its reproducibility and it can be a reference for using this system for the next generation of KSLV system.

• Fire Science and Engineering
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• v.22 no.2
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• pp.104-107
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• 2008

Heat release rates of main combustibles in residence area were measured by a calorimeter using oxygen consumption method. It was found that the peak heat release rates of the combustibles were 1.0MW for a refrigerator, 0.8MW for a desk, 4.2MW for a wardrobe and 0.4MW for a bed. Especially, the refrigerator and wardrobe were found to be very hazardous because of their fast fire growth rate.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.9
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• pp.4001-4007
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• 2011

In this study, we selected ten normal women in their 20's and 4 weeks measured Exercise Intensity, Voluntary Ventilation, Respiratory Exchange Ratio, Oxygen and Calorie Consumption and Ventilation Equivalent of them during Normal Gait, Splint-equipped Gait and Crutch Gait With Splint in order to find out whether the movement limitation and the weight of orthosis could have an effect on energy consumption. Each gait was conducted at a comfortable speed, 2.74 km/h for 30 minutes equipped with splint whose average weight is 1.2 kg. In the result of the study, The Crutch Gait With Splint showed high Exercise Intensity compaired to Normal Gait and Splint-equipped Gait. In addtion, in The Voluntary Ventilation and Oxygen Consumption, The Crutch Gait showed higher figures than two the others and the difference was significant as well(p<0.05). As for The Calorie Consumption, it also showed higher figures than two the others but the difference was not statistically significant. Finally, in The Respiratory Exchange Ratio and The Ventilation Equivalent, there was no significant difference among three conditional variables.

• 건강소식
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• v.32 no.4 s.353
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• pp.20-21
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• 2008

따스한 봄볕에 이제는 옷을 한 겹씩 벗어놓아야 할 때다. 지난 겨울 옷으로 꽁꽁 감춰두었던 내 몸매에 대한 관심이 서서히 살아나면서 이맘 때쯤 다이어트에 대한 갈망이 더욱 커지기 마련이다. 그러나 나른해지기 쉽고, 겨우내 움츠렸던 신체 활동량이 늘어나면서 식욕이 돋아나는 봄에는 다이어트가 쉽지 않다. 게을러지기 쉬운 봄에 꼭 필요한 다이어트는 바로 유산소 운동. 산소운동이란 역기 등 무거운 기구를 이용하여 단시간 내에 체력을 모하는 무산소운동과는 달리 달리기, 줄넘기, 조깅 등 체내 산소소모량을 가능한 한 많이 늘릴 수 있는 운동을 말한다. 봄철 올바른 운동법과 생활 속에서 쉽게 할 수 있는 유산소운동에 대해 알아보자.