• Korean Journal of Applied Biomechanics
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• v.22 no.2
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• pp.151-158
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• 2012

The purpose of this study was to investigate variables of significantly difference as the structure of the spine, pelvic deviation and foot pressure between undergraduates and golf player subjects. The subjects of study were composed of 20 male golf players and 20 male undergraduates. Both groups were right handed persons. The measurement tools of this study were Formetric 4D(Diers, Germany) which is a three dimensional measure. The result are the follows: there were a significant difference between golf players and general students of trunk imbalance, pelvic tilt, pelvic torsion, pelvic rotation, surface rotation, lumbar lordotic curve, foot pressure(fore & behind foot), weight distribution(right & left foot). In conclusion, golf players might cause transform of spine and foot pressure due to golf exercise for several years. Such as imbalance affect to induce functional impairment and pain of musculoskeletal system, and appropriate evaluation and treatment were necessary for golf players.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2002.09a
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• pp.75-82
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• 2002

The Mononobe-Okabe method is generally used to evaluate the dynamic earth force for the seismic design of retaining walls. However, the Mononobe-Okabe method does not consider the effects of the dynamic interactions between the backfill soil and the wall. In fact, a phase difference exists between the inertia force and the seismic earth pressure. In this study, shaking table tests were peformed on gravity walls retaining dry backfill sand to analyze the influence of several parameters (the unit weight of the wall, the input acceleration and base friction) on the development of the seismic earth pressure. The experiments revealed that the magnitude of the inertia force mobilized during seismic loading affected the seismic earth pressure. The difference in the phase angles between the inertia force and the seismic earth pressure was retained at 180 degrees before the wall failed but its magnitude changed significantly as the wall began to fail.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.4 s.97
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• pp.46-56
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• 1999

A semi-actively controlled impact system which adjusts an impulse exerted by the external impact is studies. The main control variables are internal pressure difference inside the cylinder and the shock absorber displacement while it travels. Compared to a conventional one so called a passive system with a variable orifice inside the cylinder, a semi-actively controlled system utilizes an external orifice controlled by a highly fast responding electrical proportional valve. This device overcomes the temperature and viscosity change due to continuous operating and keeps the desired pressure difference and displacement in every operation. In this article a new prototype impact system is designed and manufactured based on a semi-actively control system. Through computer simulations and experiments, we verify the possibility of controlling the shock absorber pressure and displacement. After investigating the control performance a modified semi-actively controlled system with better control performance is also proposed.

• Journal of Environmental Science International
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• v.31 no.12
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• pp.999-1012
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• 2022

To investigate the reason for the spatial difference in PM_2.5 (Particulate Matter, < 2.5 ㎛) concentration despite a similar synoptic pattern, a synoptic analysis was performed. The data used for this study were the daily average PM_2.5 concentration and meteorological data observed from 2016 to 2020 in Busan and Seoul metropolitan areas. Synoptic pressure patterns associated with high PM_2.5 concentration episodes (greater than 35 ㎍/m³) were analyzed using K-means cluster analysis, based on the 900 hPa geopotential height of NCEP (National Centers for Environmental Prediction) FNL (Final analysis) data. The analysis identified three sub-groups related to high concentrations occurring only in Busan and Seoul metropolitan areas. Although the synoptic patterns of high PM_2.5 concentration episodes that occur independently in Busan and Seoul metropolitan areas were similar, there was a difference in the intensity of pressure gradient and its direction, which tends to be an important factor determining the movement time of pollutants. The spatial difference in PM_2.5 concentration in the Korean Peninsula is due to the difference and direction of the atmospheric pressure gradient that develops from southwest to northeast direction.

• Journal of the Korean Society for Railway
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• v.12 no.1
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• pp.65-71
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• 2009

The pressure transient inside the passenger cabin of high-speed train has been assessed using computational fluid dynamics (CFD) based on the axi-symmetric Navier-Stokes equation. The pressure change inside a train have been calculated using first order difference approximation based on a linear equation between the pressure change ratio inside a train and the pressure difference of inside and outside of the train. The numerical results show that the pressure change inside the new Korean high-seed train passing through a tunnel of Seoul-Busan high-speed line at the speed of 330km/h satisfied well the Korean regulation for pressure change inside a passenger cabin if the train is satisfying the train specification for airtightness required by the regulation.

• Proceedings of the IEEK Conference
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• 1999.11a
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• pp.1067-1070
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• 1999

Anesthesia gas to pour to patients affects the flow and volume as the pressure difference of an oxygen and an anesthesia gas. An anesthesia gas, being injurious and polluting an environment, must control the pressure of an oxygen gas because of being used by closing up tight. But a pressure sensor to use for measuring an oxygen gas appears other pressure as the characteristic and the error difference of elements to use for implementing an system. A medical machine such as an anesthesia ventilator must be accurate because of using for the person's body. So we intend to implement an system for a sensor pressure measurement not to be change regardless of an environment. This papers is the target that a sensor pressrue measurement to be changed in environment is equal to actual sensor pressure measurement. So an implemented system is using analog filter and digital filter to reduce a noise. And we are using auto-zeroing and calibration to correct a sensor pressure which is changed in environment. Through such a process we increase the accuracy and the confidence of an anesthesia ventilator by controlling the flow of an anesthesia gas.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.19 no.3
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• pp.220-227
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• 2007

Heat transfer and momentum transfer under conditions of both oscillating flow and oscillating pressure within pulse tubes show very different behavior from those for steady state conditions. The analytic solutions of axial velocity and temperature of the gas within pulse tubes were obtained by assuming that the variations in pressure and temperature were purely sinusoidal and small. The shear stress and the heat flux at the tube wall obtained from the solutions are expressed in terms of the cross-sectional averaged velocity, the difference between mean temperature and instantaneous cross-sectional averaged temperature and the difference between mean pressure and instantaneous pressure. It is shown that the complex shear factor, which has been applied to momentum transfer of incompressible oscillating flow, and the complex Nusselt number, which has been applied to either heat transfer with oscillating pressure only or heat transfer of incompressible oscillating flow, could also be used for momentum transfer and heat transfer subjected to both oscillating flow and oscillating pressure, respectively.

• The Research Journal of the Costume Culture
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• v.1 no.2
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• pp.131-144
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• 1993

Even though it has been to research on the variance of clothing pressure and on its effect of human body, it has not been available to evaluate the clothing pressure as an objective standard ta for the determination of an extra quantity of bodice' basic pattern. In this paper the basic pattern(the close adherence original shape) is determined by a drawing of plane figure after detaching an unweaving clothing from the inside of the gypsum, and the extra quantity is figured by a extension quantity when is formatted with 0.5, 1.0, 1.5 cm extra quantity longitudinal-cross section figures. With our experimental method, review the variance of clothing pressure according to difference of the extra quantity which was figured with subjects wearing experimental clothing including the extra quantity. The difference of the extra quantity was able to calculate with data form the subjects when anatomical position and five movements, then compare with subjects wearing non-extra quantity experimental clothing. The results of experiment as the follows : 1. There is only few body portions with the significant variance according to the increasing of he extra quantity at he body portion and the sleeve portion. 2. The clothing pressure of the sleeve portion was higher than the clothing pressure of the body portion. The difference of clothing pressure according to the variance of the extra quantity at the sleeve portion is more significant than the body portion. 3. Consider several important pressure points which wil be the No. 1 at the front of body portion. No. 17, 18 at the back of body portion and No. 21 at the sleeve portion. 4. It is important to have plane figure of gypsum when format an basis pattern.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.2
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• pp.721-727
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• 2013

This study sought to compare the difference of Phonation Threshold Pressure and Nasalance according to vowels. We tested 28 normal females(20~30age) who be in attendance at a school from May to August 2012. We measured Phonation Threshold Pressure through PAS(Phonatory aerodynamic system, model 6600, KAY electronics, Inc) that aero-mechanical instrument called. Phonation Threshold Pressure was measured by using the consonant /p/ and the three vowels /a, i, u/ and was analyzed the three times of Phonation the five times. Also We measured Nasalance through the Nasometer${\Pi}$(model 6450, KAY electronics, Inc). The vowel's phonation was recored by using the three vowels /a, i, u/. the nasalance score was measured via Nasometer. As a Result, Phonation Threshold Pressure according to three vowels show significantly difference. Also, Nasalance according to three vowels show significantly difference. Finally, Correlation coefficient of Phonation Threshold Pressure and Nasalance according to three vowels show positive relation ship. Therefore Phonation Threshold Pressure and Nasalance according to three vowels have closely relationship.

• Journal of Korean Public Health Nursing
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• v.17 no.1
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• pp.144-152
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• 2003

The purpose of this study is to identify the prevalence rate of hypertension and diabetes a in the urban communities and to provide the basic data for development of health promot The subjects of this study were 526 people over the age of 20, living in Seoul. Data for this collected from June 19, 2001 to September 25, 2001. The results of this study are as follows: 1. The subject group is comprised of males, $57.4\%$ and females, $42.6\%$. Their ages range from 20 to 89, and the weights from 40 to 94 kilograms. 2. In the systolic blood pressure, $36.1\%$ showed high, $56.5\%$ normal. and $7.4\%$ low. In the diastolic blood pressure, $50.5\%$ showed high, $48.9\%$ normal, and $1.7\%$. low. In the blood glucose, $70.3\%$ showed normal. $27.9\%$ high, and $1.7\%$. low. 3. There was a significant difference in the mean(SD) of the systolic blood pressure by age(p=.017) and weight(p=.005). Another significant difference was found in the mean (SD) of the diastolic blood pressure by age(p=.006) and weight(p=.007). There was a significant difference in the mean(SD) of the blood glucose by sex and age(p=.001). 4. There were significant correlations between the blood pressure and the blood glucose and the sex, age and weight. 5. The multiple regression analysis showed that the age and weight explained $9.9\%$ of the systolic blood pressure, that the weight and age explained $7.1\%$ of the diastolic blood pressure, and that the age and systolic blood pressure explained $7.0\%$ of blood glucose. The results were useful in developing health promotion programs. This study suggests that a further study be needed.