• Journal of the Korean Society of Propulsion Engineers
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• v.9 no.3
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• pp.38-48
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• 2005

For the development of Scramjet engine technology, intake designing processes are investigated. The basic geometry is determined by the inviuld relation such as shock wave relations and geometric relations. Furthermore, bleed duct is installed for preventing boundary layer development and shock wave impingement. Performance of the designed intake is validated by numerical analysis. As a result, double- wedge intake showed better characteristics in total pressure recovery than single-wedge intake.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.03a
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• pp.480-485
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• 2008

In this study, two types of ramjet intake were designed for the flight condition of Mach number 2 and 5 and numerical analysis was performed. In order to widen the flight envelope range(Mach number $2{\sim}6$), movable intake concept was applied. The central body was designed so that the capture area ratio which is one of most important factors of ramjet intake design could be adjusted. And various types of cowl and movable insert part of shell were designed in order to control throat area which could increase total pressure recovery. The numerical results showed that the designed ramjet intake could be applied in various flights Mach number.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.6
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• pp.1045-1049
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• 1996

Purpose of this study was to investigate correlation between blood pressure(systolic and diastolic) and dietary Na, K intake pattern in the family members of normal and hypertension disease patients, besides patients themselves. Mean values of $systolic(126.6\pm18.0$ vs $119.3\pm17.2mmHg)$ and diastolic $(77.6\pm14.6$ vs $71.6\pm12.5mmHg)$ blood pressure in the family members of hypertension patients were significantly higher than those of normal subjects. Systolic blood pressure in normal subject group was positively correlated with age, body weight, sodium in soybean paste, and was negatively correlated with potassium in hotpepper paste, soybean paste and meats. Systolic blood pressure in the family member of hypertension patient was positively correlated with age, body weight, sodium in soybean Paste, and table salt intake, but urinary potassium excretion was negatively correlated. Diastolic blood pressure was positively correlated with age, body weight, and table salt intake, and was negatively correlated with potassium in hotpepper paste and soybean paste in normal subjects groups. In the family members of hypertension patients group, diastolic blood pressure was positively correlated with age, body weight, and table salt intake, and was negatively correlated with sodium in hotpepper Paste and soybean paste and urinary potassium excretion. In total, tendency of negative correlation between Na intake pattern and systolic blood pressure in normal subjects was much obvious than that in the family members of hypertension patients. Urinary potassium excretion in the family members of hypertension patients was also negatively correlated with both systolic and diastolic blood pressure.

• Transactions of the Korean Society of Automotive Engineers
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• v.5 no.6
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• pp.175-182
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• 1997

The purpose of this study is to investigate the effects of intake manifold shapes to improve the engine performance in a 3-cylinder LPG engine with a closed loop fuel supply system. To know the flow resistance of intake manifolds with shape, the intake negative pressure of each runner in intake manifolds were measured by using the digital pressure meter at each driving condition. And, the engine torque and power have been measured with an engine dynamometer while adjusting the optimal fuel consumption ratio with a solenoid driver. As 속 results form this experiment, the torque characteris- tics were more improved with the plenum chamber(B type intake manifold) than with the banana type(A type intake manifold). The torque characteristics were improved at mid-engine speed(rpm) range as the inner diameter of the intake manifold became smaller. And also the optimum volume among the examined plenum chamber volume was 0.74 times(590cc) the displacement of the test engine.

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.5
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• pp.35-44
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• 2002

Engine cycle simulation using a two-zone model was performed to investigate the effect of the engine parameters on NO and soot emissions in a DI diesel engine. The present model was validated against measurements in terms of cylinder pressure, BMEP, NO emission data with a 2902cc turbocharger/intercooler DI diesel engine. Calculations were made for a wide range of the engine parameters, such as injection timing, ignition delay, Intake air pressure, inlet air temperature, compression ratio, EGR. This parametric study indicated that NO and soot emissions were effectively decreased by increasing intake air pressure, decreasing inlet air temperature and increasing compression ratio. By retarding injection timing, increasing ignition delay and applying EGR. NO emission was effectively reduced, but the soot emission was increased.

• Journal of the korean Society of Automotive Engineers
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• v.13 no.6
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• pp.48-56
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• 1991

This paper describes the experimental investigations on the pressure variations of intake and exhaust manifold and mass flow rate through exhaust turbine of turbocharged 6-cylinder diesel engine. The turbocharger of experimental diesel engine is constructed with the radial ty pe exhaust turbine and blower driven by exhaust gases. The pressure variations were measur ed by pressure transducer at the points such as turbine inlet and outlet, compressor inlet and outlet, and inlet pipe and exhaust manifolds for normal and combined charging engines with the change of engine speed. The experimental results of this study show that the mass flow rate of exhaust turbine and the variations of pressure in intake and exhaust manifold are all increased with the increase of engine speed.

• Journal of Nutrition and Health
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• v.20 no.1
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• pp.25-37
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• 1987

The purpose of this study was to estimate the sodium and potassium intakes and their metabolisms of preschool children, and to evaluate the relationship between the blood pressure and the related variables. The subjects consisted of ninety-five preschool children aged two to six years (male 57, female 38). Twenty-four hour urines of subjects were collected for the measurements of their volume, sodium, potassium, creatinine and urea nitrogen. At the same time, the questionnaire was designed to assess the sodium and potassium intakes. The' results obtained were as follows; 1) The urinary excretion of sodium in 24 hours was 54.6$\pm$22.4mEq(orI255.8mg)and dietary sodium intake was 2147.0$\pm$518.4mg. The dietary sodium intake significantly increased with increasing age(p=O.0151). However, daily sodium intake per unit body surface area did not show significant difference by age. 2)The urinary excretion of potassium in 24 hours was 14.2$\pm$7.6 mEq (or 555.2mg) and the potassium intake was 1133.8mg. 3) The urinary excretions of creatinine and urea nitrogen were 240.2$\pm$126.2mg and 2946.7$\pm$1693.9mg, respectively. 4) The principal food SOUTce of sodium intake was the seasoning group, which con\ulcornertributed 49.9% to total sodium intake. 5) The main food source of potassium intake was milk and milk products; from which 28.6% of total potassium intake was obtained. 6) The blood pressure showed highly positive correlations with height, weight and body surface area (p$\leq$O.OOl) . In addition, the blood pressure was found to be correlat\ulcornered with urinary sodium excetion and dietary sodium intake (p$\leq$O.Ol).

• Journal of the Korean Dietetic Association
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• v.8 no.3
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• pp.250-259
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• 2002

The purpose of this study was to confirm that calcium intake and healthy status play a role in reducing the risk of cardiovascular disease, to assure that calcium intake and regular exercise are important in reducing serum lipid levels in middle-aged women. Daily nutrient intakes were analyzed by convenient method. Anthropometric measurement such as body weight and height and blood pressure were measured. The subjects divided into two groups : women in group I under 50 years of age($\leq$49 yr group) and those in group II 50 years up($\geq$50 yr group). Average ages of group I and II were 43.87 and 53.46 years. The nutrients intake of subjects were higher than Korean recommended dietary allowances(KRDA) except calorie, iron, calcium, vitamin B1. They showed significant difference each other in vitamin B2(p<0.05), calcium(p<0.01) intake. Mean daily calcium intake was 540.88mg in $\leq$49 yr group and 519.50mg in $\geq$50 yr group. The levels of serum cholesterol, triglyceride, blood pressure, Atherogenic Index(AI), LDL/HDL and Cardiac Index(CI) were increased with age. The triglyceride and total cholesterol concentrations and LDL/HDL in $\geq$50 yr group were significantly higher than those of $\leq$49 yr group. There was a highly significantly positive correlation between age and triglyceride, total cholesterol and Atherogenic Index(AI). Triglyceride, total cholesterol, LDL-cholesterol concentration and Atherogenic Index(AI) were positively correlated with body weight and WHR(waist-hip ratio). Also ther was a significantly negative correlation between exercise and Cardiac Index(CI). Also a significantly negative correlation was found between Ca intake and LDL-cholesterol. Exercise and Cardiac Index(CI) also had a significantly negative relation. The results suggest that increased habitual physical activity and calcium intake should be recommended as a way of decreasing blood lipids and blood pressure in middle-aged women.

• Journal of Korean Clinical Nursing Research
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• v.20 no.1
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• pp.113-122
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• 2014

Purpose: The purpose of this study was to examine the effects of drinking water on the change in blood pressure after spinal surgery. Methods: A quasi-experimental nonequivalent control group, pretest and posttest design was employed. Subjects were consisted of 40 elderly patients who underwent spine surgery (20 in the experimental group, 20 in the control group). Data were collected from May 9th to September 30th, 2013. The experimental design involved patients drinking 400 mL of water in 5 mins after surgery and the blood pressure was measured in a standing position following the first 30 minutes after surgery. Control group received the same treatment and care as experimental group, except for the water intake. Data were analyzed using SPSS WIN 19.0 for $x^2-test$, t-test and independent t-test. Results: Experimental group with water intake demonstrated a significant higher level of systolic blood pressure compared to the control group (t=9.065, p=.005), but showed a non-significant level of diastolic blood pressure. Conclusion: This study indicates that water intake can be utilized as a useful nursing intervention to monitor changes in systolic blood pressure in elderly patients after spinal surgery.

• Transactions of the Korean Society of Automotive Engineers
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• v.20 no.1
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• pp.88-94
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• 2012

One of the effective ways to reduce both $NO_x$ and PM at the same time in a diesel CI engine is to operate the engine in low temperature combustion (LTC) regimes. In general, two strategies are used to realize the LTC operation-dilution controlled LTC and late injection LTC - and in this study, the former approach was used. In the dilution controlled regime, LTC is achieved by supplying a large amount of EGR to the cylinder. The significant EGR gas increases the heat capacity of in-cylinder charge mixture while decreasing oxygen concentration of the charge, activating low temperature oxidation reaction and lowering PM and $NO_x$ emissions. However, use of high EGR levels also deteriorates combustion efficiency and engine power output. Therefore, it is widely considered to use increased intake pressure as a way to resolve this issue. In this study, the effects of intake pressure variations on performance and emission characteristics of a single cylinder diesel engine operated in LTC regimes were examined. LTC operation was achieved in less than 8% $O_2$ concentration and thus a simultaneous reduction of both PM and $NO_x$ emission was confirmed. As intake pressure increased, combustion efficiency was improved so that THC and CO emissions were decreased. A shift of the peak Soot location was also observed to lower $O_2$ concentration while $NO_x$ levels were kept nearly zero. In addition, an elevation of intake pressure enhanced engine power output as well as indicated thermal efficiency in LTC regimes. All these results suggested that LTC operation range can be extended and emissions can be further reduced by adjusting intake pressure.