• Proceedings of the KSME Conference
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• 2004.11a
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• pp.1698-1703
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• 2004

To understand the high expansion effects by adopting intake closing time in the cases of compensating intake air-mass and effective compression ratio simultaneously, fundamental study was carried out by using RICEM realizing Atkinson cycle. Intake air-mass and effective compression ratio were compensated by increasing supercharged pressure and geometric compression ratio. The results showed that the increasing rates of expansion ratio and expansion-compression ratio were increased by compensating both a intake air-mass and effective compression ratio the same tendencies were obtained with the increases of compression ratio and cut off ratio It was also found that LIVC has more advantages in expansion ratio and effective work than those of EIVC under above conditions.

• International Journal of Automotive Technology
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• v.6 no.6
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• pp.579-584
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• 2005

Unsteady state free natural gas jets injected from several types of injectors were numerically simulated. Simulations showed good agreements with the schlieren experimental results. Moreover, injections of natural gas in intake manifolds of a single-valve engine and a double-valve engine were predicted as well. Predictions revealed that large volumetric injections of natural gas in intake manifolds led to strong impingement of natural gas with the intake valves, which as a result, gave rise to pronounced backward reflection of natural gas towards the inlets of intake manifolds, together with significant increase in pressure in intake manifold. Based on our simulations, we speculated that for engines with short intake manifolds, reflections of the mixture of natural gas and air were likely to approach the inlets of intake manifolds and subsequently be inbreathed into other cylinders, resulting in non-uniform mixture distributions between the cylinders. For engines with long intake manifolds, inasmuch as the degrees of intake interferences between the cylinders were not identical in light of the ignition sequences, non-uniform intake charge distributions between the cylinders would occur.

• Journal of Nutrition and Health
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• v.37 no.7
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• pp.509-514
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• 2004

This study was conducted to investigate the supplementary effects of Lentinus edodes on blood pressure and blood lipid levels in the Hypertensive Rat. We supplied 3 kinds of experimental diets (Control; CO, cap of Lentinus edodes; LC, and stipe of Lentinus edodes; LS) to spontaneously hypertensive rats (SHR) for 8 weeks. Diet intake, body weight, organ weights, and serum lipid levels were measured. There was no significant difference in diet intake, and body, liver and epididymal fat pad weights among experimental groups. The levels of systolic and diastolic blood pressure were significantly lower in LC and LS groups than CO group. The concentrations of serum total cholesterol were lower in LC and LS groups than CO group. These results suggested that Lentinus edodes decrease blood pressure levels and serum total cholesterol concentration in the spontaneously hypertensive rats. But these effects of Lentinus edodes didn't show any significant difference between animals fed cap and stipe of this mushroom.

• Transactions of the Korean Society of Automotive Engineers
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• v.2 no.6
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• pp.76-86
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• 1994

Combustion of diesel engine depends on the mixing of air and evaporating fuel during ignition delay greatly. Variation of air-fuel mixing rate and ignition delay for engine operating condition causes difference of combustion, performance and exhaust emissions. This study is investigated in a turbocharged diesel engine of IDI swirl chamber type. In the results, As injection timing is advanced until $12.6^{\circ}$ BTC, ignition delay decreases. NOx concentration and smoke level in exhaust gas increases for advanced injection timing Ignition delay, combustion period, pressure rise rate and exhaust gas temperature are increased with increasing engine speed. And ignition delay at high load is more decreased than that at low load. Ignition delay and combustion period are decreased with increasing intake pressure. Power increases, temperature and CO, NOx concentration in exhaust gas decreases as intake pressure increases. With increasing load, ignition delay is decreased and combustion period, motoring pressure are increased.

• Journal of the Korea society of information convergence
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• v.7 no.2
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• pp.25-29
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• 2014

In this study, it examined the effects of alcohol on the physiology of the eye and ocular function. It was measured to IOP(intraocular pressure), tear secretion, stereoscopic parallax, AC A ratio, convergence ability, divergence ability alcohol intake before and after. The results were as follows. The mean IOP before alcohol intake 15.14mmHg and the mean IOP after alcohol intake 12.8mmHg. Average decreased 15.44%. The mean tear secretion before alcohol intake 17.125mm and the mean secretion after alcohol intake 9.875mm. Average decreased 42.33%. Stereoscopic parallax has increased by about four times that 40' before alcohol intake to 165' after that. AC/A ratio has increased by 14.6% that $5.40{\Delta}/D$ before alcohol intake to $6.19{\Delta}/D$ after that. Convergence and divergence ability was no significant change in both distance and close range.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.3
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• pp.977-985
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• 2012

Performance optimization of a small engine intake port has been studied through computational and experimental approach. Port angle, flange area and port shape are very important design parameters affecting performance of an intake port. Especially, radius of curvature of intake port inner surface has major effect on the flow coefficient of an intake port. As increasing port angle and flange area, flow coefficient is increased because pressure distribution and pressure gradient in the intake port are improved. Even though computational results over-predict maximum 8% compared with experimental result, they describe the tendency of flow coefficient according to the design parameters. Optimized intake port shows about 4.5% improved flow performance.

• Nutrition Research and Practice
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• v.1 no.2
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• pp.131-142
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• 2007

The purpose of this study was to investigate differences in the body composition, dietary habits, daily intake of nutrients and clinical blood indices in female college students by body mass index of normal weight, overweight and obese. The subjects of this research were 141 respondents of a survey carried out on students, and subjects were given 60 minutes to answer questionnaires, by recording their own answers. The average heights and weights of subjects by BMI were 162.17 cm, 52.73 kg in normal weight group, 162.35 cm, 62.22 kg in overweight group and 161.72 cm, 69.82 kg in obesity group, respectively. As for the survey daily of meals, starving breakfast and kind of snacks of subjects were significantly different among the groups by BMI. In animal protein food intakes, meat intake was the highest 'every day' food consumed by subjects, and there was a significant difference in distribution of BMI among subjects. Fruits, and greenish and yellow vegetables intakes were the highest 'every day' foods indicated by the normal weight group. Consumption of carbonated beverages and juices showed a significant difference among groups by BMI. The average of total-cholesterol was the overweight group was the higher value. There was a significant difference in diastolic blood pressure and systolic blood pressure among the groups by BMI. Average daily calories intake levels were insufficient and the intake ratio of carbohydrates, protein, and fat was the normal weight group 68 : 17 : 15, the overweight group 64 : 18 : 18 and the obese group 73 : 14 : 13. Results of the daily vitamin intake analyses displayed riboflavin, niacin, vitamin C, and folic acid levels lower than the RI levels. Fe intake was the normal weight group 81%, overweight group 76%, obese group 59% of the RI level. Therefore, it is necessary for college students to establish regular meals, good quality snacks and consuming more vitamin and mineral nutritions for optimal health conditions.

• Journal of the Korean Home Economics Association
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• v.33 no.6
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• pp.89-97
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• 1995

This study was undertaken to examine the correlations between dietary intakes or anthropometric parameters and the plasma lipid level. measurements of dali nutrients intake, body weight, height, body bass index, skinfold thickness, blood pressure, plasma total lipid, triglyceride and cholesterol were made to each of 124 healthy adult(25-59yrs) : 56 males and 65 females. The mean energy and nutrients intake, anthropometric parameters and plasma lipid levels were all in normal range. In females, the fat and protein intake, the amount and percents to total energy intake, had positive association with the plasma total lipid, but the energy percent from carbohydrate intake was correlated negatively. And body mass index positively correlated with plasma total lipid level, in male and female, Therefore we could postulated the dietary fat intake and body mass index affected to plasma lipid levels in normal conditions of healthy adult.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.11a
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• pp.202-207
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• 2006

The aeroacoustic noise from intake head of a vacuum cleaner is caused by complicated transient pressure fluctuation and it greatly affects the overall SPL of the vacuum cleaner. In this study, we intended to decrease the overall SPL by reducing the aeroacoustic noise from intake head. In the first the place, we analyzed the aeroacoustic noise from the unsteady fluid analysis of intake head. And then, we grasped the dominant frequency band from the aeroacoustic noise by comparing the spectrum distributions between examinations and analyses. Also, we systematically investigated the aeroacoustic noise sources from each part composing the intake head. Consequently, we redesigned each part of the dominant noise sources and suggested the modified intake head, resulting in the reduction ortho overall SPL by 3.6dB(A).

• Journal of Nutrition and Health
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• v.30 no.6
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• pp.669-678
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• 1997

This study was designed to estimate the sodium intake of preschool children . To determine the sodium intake & excretion of preschool children in Korea, dietary behaviors, anthropometry, intakes of dietary nutrients, urinary sodium excretion and preference for salty foods were measured in 42 preschool children (male 26 , female 16, average6.5 years old) and their mothers. The results are summarized as follows. Mean daily urinary sodium excretion was 52.7 mEq(1,212.1mg). This value did not show remarkable change compared with the other studied that were accomplished in the similarage group for about the last ten years. And the subjects showed lower preference for salty taste than those of elementary school children and adults. Mean daily lower preference for salty taste than those of elementary school children and adults. Mean daily urinary sodium excretion were significantly correlated with the frequency of eating out (p<0.01), potassium intake(p<0.001) and urinary sodium to potassium excretion ratio(p<0.001). But there weren't any correlations with mean daily sodium intake, blood pressure, dietary nutrients intake and the preference for salty taste.