• Transactions of the Korean Society of Automotive Engineers
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• v.19 no.5
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• pp.29-34
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• 2011

This study investigates the potential of DME/Diesel dual fuel engine for reducing emissions with same power. Dual fuel engine controls the combustion using two different fuels, DME and diesel with different auto-ignition timings. In the previous work, the caracteristics of combustion and emissions under single cylinder engine and ignition is done by compression ignition. Pre-mixture is formed by injecting low-pressure DME into an intake manifold and high-pressure fuel (diesel or DME) is injected directly into the cylinder. Both direct diesel injection and port fuel injection reduced the significant amount of Smoke, CO and NOx in the homogeneous charge compression ignition engine due to present of oxygen in DME. In addition, when injecting DME directly in cylinder with port DME injection, there is no changes in emissions and energy consumption rate even operated by homogeneous charge compression ignition.

• Journal of the Korean Society of Combustion
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• v.5 no.2
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• pp.37-50
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• 2000

In the present study, a systematic chemical kinetic calculations were made to investigate the augmentation of $NO-NO_2$ conversion due to the addition of various hydrocarbons (methane, ethylene, ethane, propylene, propane) in the nonthermal plasma treatment. It is included in the present conclusion that the reaction between hydrocarbon and oxygen radicals induced by electron collision, is believed to be a primarily process for triggering the overall NO oxidation and the eventual NOx reduction. Upon the completion of the initiating step, various radicals (OH, $HO_2$ etc.) successively are produced by hydrocarbon decomposition form the primary path of $NO-NO_2$ conversion. When the initiating step is not activated, hydrocarbon consumption rate appeared to be very low, thereby the targeted level of NO conversion can only be achieved by the addition of more input energy. Present study showed ethylene and propylene to have higher affinity with O radical under all conditions, thereby both of these hydrocarbons show very fast and efficient $NO-NO_2$ oxidation. It was also shown that propylene is superior to ethylene in the aspect of NOx removal.

• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.576-580
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• 1997

Lipoxygenase activity in Chinese cabbage was measured at various concentrations of brines. Lipoxygenase activity on linoleic acid substrate was determined by changing the rate of dissolved oxygen consumption. The inactivation of lipoxygenase by salting was increased when concentration of sodium chloride and soaking time were increased. About 60% of enzyme activity was reduced after submerging in 13% brine solution for 5 hr. The addition of calcium chloride (0.7%) reduced about $10{\sim}15%$ of lipoxygenase activity rather than without. Residual activity of lipoxygenase in Chinese cabbage submerged in 13% brine was 20% and about 60% of lipoxygenase was also inhibited by addition of garlic extract.

• Korean journal of applied entomology
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• v.26 no.3 s.72
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• pp.145-150
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• 1987

Carborhydrate contents were compared between diapausing and non-diapausing pupae of the fall webworm, Hyphantria cunea DRURY. Glycogen content in the whole body of diapausing pupae kept at $-5{\pm}1^{\circ}C$ was less than that of those left at room temperature, while the amounts of trehalose and sorbitol showed the reverse trend. The osmotic pressure of haemolymph was higher in diapausing pupae than that in non-diapausing pupae. The mean oxygen consumption rate of diapausing pupae was $4{\sim}6.7$ times less than that of non-diapausing, normal pupae.

• The Korean Journal of Malacology
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• v.14 no.1
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• pp.51-59
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• 1998

담수산 이매패류인 참재？, Corbicula leana를 대상으로 크기와 수온별로 카드뮴, 구리 및 수은 등의 중금속에 노출시켜 반수치사농도, 호흡률 및 여수율 등의 생리적 내성에 관하여 알아보았다. 17%C에서 작은 개체rnhr,-LC$^{50}$ 은 수은이 1.63 ppm이었으며, 카드뮴과 구리는 각각 7.45및 8.71 ppm으로서 수은에 비해 상당히 높은 값을 나타내었다. 큰 개체구의 경우는 수은이 2.62ppm이었으며, 카드뮴과 구리가 각각10.15와 10.20 ppm이었다. 22$^{\circ}C$의 경우 작은 개체구의 96 hr-LC$^{50}$ ppm은 카드뮴, 구리 및 수은이 각각 5.94, 7.08및 1.63 ppm이었으며, 큰 개체구에서는 각각 8.29, 8.35, 1.87ppm으로서 두수온구에서 모두 작은 개체구에서 중금속 오염원에 의한 영향이 컸으며, 독성순위는 수은>카드뮴>구리 순이었다. 한편 중금속 오염원에 노출시킨 참재첩의 수온-개체크기별 산소소비율과 여수율은 오염원의 농도증가에 따라 고수온에서 영향을 많이 받았으며, 특히 수은의 경우, 22%C-작은 개체구에서 호흡률이 50.7%, 여수율이 52.15%감소되고 있어 여수율이 보다 크게 영향을 받았다.

• Journal of Advanced Marine Engineering and Technology
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• v.33 no.6
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• pp.896-902
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• 2009

EGR is applied in order to lower temperature of combustion chamber by using the specific heat of carbon dioxide in engine exhaust gas. However, the problem of EGR system in diesel engine is high PM concentration. Combined EGR system can be reduced it by mixing exhaust gas of gas engine into the intake air of diesel engine. This experimental study was designed for EGR system for both engines use. The results of EGR experimental study by using diesel engine and gas engine are as follows. 1) The pressure of combustion and rate of heat release decreased. 2) The specific fuel consumption increased. But, up to middle load, it little increased. 3) NO concentration has decreased up to 50% in almost all combustion area. 4) The variation of the PM concentration at low load is not so seen. But at high load, PM increased rapidly when concentration of oxygen is decreased and most of it caused the increasing of Dry Soot.

• YAKHAK HOEJI
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• v.37 no.1
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• pp.84-88
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• 1993

Brovincamine is a selective cerebral vasodilator that was apparently produced via a slow calcium blockade. Brovincamine has been shown to increase ATP production and glucose and oxygen consumption in brain, improving energy metabolism. Also brovincamine inhibited platelet aggregation induced by ADP and collagen in vivo and in vitro via an increase of cAMP concentration, promoting therapeutic effects on cerebral circulatory disorders. So we investigated and represented the clinical effects and safety of brovincamine in patients with cerebral stroke. Thirty patients of cerebral stroke that was older than 2 months, who were 22 cases of cerebral infarction, 6 of cerebral embolism that originated from carebral infarction, 6 of cerebral embolism that originated from cardiac diseases, and 2 of cerebral embolism that originated from cardiac diseases, and 2 of cerebral hemorrhage, were administered of 20 mg of oral brovincamine three times daily for 8 weeks. Improvement rates of each symptom after 8 week administration were 30.8% for subjective symptoms, 76% for psychiatric symptoms and 65.6% for neurologic symptoms. In final global improvement rates, much improvement was 10%, improvement was 23.3% slight improvement is 36.7%, and no change was 30%. So global improvement rate including slight improvement was 70%. As for side effects, there were 3 cases of mild gastrointestinal symptoms, but there were no other subjective side effects and significant fluctuation in laboratory examination. Conclusively throughout the present study, brovincamine is judged to be well tolerated and effective in patients with cerebral stroke.

• Fire Science and Engineering
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• v.24 no.1
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• pp.128-133
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• 2010

The aim of study intends to investigate effect of weight of fire fighting protective equipment for physical activity ability and to provide the base data for the safety of firefighter. The results of the study are as follows. The maximum all-out time is short about 18.8% in weight-jacket case which weight is same with fire-protective equipment than case of gym suit. The maximum oxygen consumption increased 17.6% in gym suit case than case of weight-jacket. The maximum heart rate is high 5.4% in gym suit case than case of weight-jacket.

• Journal of Life Science
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• v.18 no.10
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• pp.1455-1463
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• 2008

The purpose of this study was to evaluate the effect of various exercise intensity on Excess post exercise energy expenditure (EPEE), Resting Metabolic Rate (RMR),thyroid hormonal changes and biochemical variables in obese and NIDDM patients. The subject of the present study were divided into four groups and four periods: trained (T; n=10), control (C; n=10), obese (O; n=10) and NIDDM (N; n=10) group. And the periods were divided as follows; Resting (RE), Maximal (MA), High intensity (HI), and Low intensity (LI). There was significant difference in RMR among different intensity of exercise. in the T (p<0.05) not in the C, O, and N groups. however, there was no significant different percent body fat among all groups. In the energy expenditure, there was significant different among C, O, N groups compare to T in HIEE (high intensity exercise energy expenditure), LIEE (low intensity exercise energy expenditure), HIEEPE (high intensity exercise energy expenditure post exercise) and LIEEPE (low intensity exercise expenditure post exercise). In the hormonal level, there was significant different in T4 level in the T group at LI period and there was also significant difference in T4, Free T3, & Free T4 levels in T group at LI period, however there was no significant different in the O and N groups except LI period. In the fatigue variables, there was significant different in lactate and ammonia levels in the N group in the period of HI compare to C. The present cross-sectional study was design to investigate the relationship between exercise intensity and RMR in four groups. The focus of this investigation was to compare RMR in aerobically trained (T), control (C), obese (O) and NIDDM (N) group. The relationship among RMR, exercise intensity and percent body fat would best be investigated using Meta Lyzer 3B, MMX3B and body composition analyzer. Each subject completed measurement of percent body fat, RMR, hormone in the period of maximal oxygen uptake exercise (MA), high intensity exercise (HI), and low intensity exercise (LI). From the results, High and Low intensity of exercise, there was a trend for an increased RMR (kcal/day) in the trained groups and control group (in case of LI) not for the obese and N groups. This is best explained not by the reduced percent body fat but by the highly induced energy expenditure (during exercise and post exercise energy expenditure) and increased T4, Free T3, and Free T4 hormonal levels in the low intensity exercise for the T group and sometimes C group.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.12 no.3
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• pp.155-160
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• 1979

Mechanical agitation in fermentation process enhances the fermentation activity of microbes by means of oxygen supply and frequent collision with substrate. However, the fermentation activity of microaerophilic bacteria is inhibited by the excess oxygen resulted from the mechanical agitation. On this account, a a strain of Lactobacillus bulgarius was cultured to know the inhibition effect of the mechanical agitation and determine the optimum conditions for tile process of lactic acid fermentation. The growth rate of L. bulgaricus and the consumption rate of tile substrate revealed an identical pattern in changes. The two rates were constant in the range of the modified Reynolds number of $1\times10^5\;to\;5\times10^5$ while they showed linear increase in the range of the modified Reynolds number of $1\times10^5\;to\;10\times10^5$. Under the conditions of the modified Reynolds number more than $10\times10^5$, the both rates decreased. At the modified Reynolds number of $10\times10^5$, the maximum specific growth rate and the saturation constant of L. bulgaricus were 0.58/hr and 6.74g/l, respectively.