• Journal of computational fluids engineering
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• v.12 no.4
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• pp.1-6
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• 2007

In the present study, the wind pressure transients on platform screen door in side platforms caused by passing trains have been investigated numerically. The transient compressible 3-D full Navier-Stokes solution is used with actual operational condition of subway train by adopting the moving mesh technique considering the train movement. To achieve more accurate analysis, the entrance and exit tunnel connecting the stations are included in a computational domain with modeling the detailed shape of the train. Numerical analyses are conducted on five operational conditions which include the variation of the train speed, case with or without the train stopped in the other track, and case for two trains passing each other inside the station. The results show that pressure load on platform screen door is maximized when the two trains are passing each other. It is also seen from the computational results that the maximum pressure variation for the cases considered in the present study is found to be satisfactory to various foreign standards.

• Journal of the Korea Convergence Society
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• v.11 no.4
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• pp.63-69
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• 2020

This study was conducted to investigate the immediate effects of abdominal pressure blet on limited of stability and gait parameter in patients after stroke. Thirty stroke patients were recruited to measured pre and post wearing the abdominal pressure belt. The assessment measured limited of stability and spatiotemporal gait parameter. This study result were significantly increase in paretic side area, non-paretic side area, forward side area, backward side area (p<.05) and cadence, gait velocity, stride length (p<.05). This study found that abdominal pressure belt had an immediate effect on improving balance and gait function in stroke patients. Future studies require studies of efficient abdominal pressure levels and intervention periods to improve the balance and walking function of stroke patient.

• Journal of the Korean Society of Clothing and Textiles
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• v.13 no.2 s.30
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• pp.109-116
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• 1989

Korean clothings are admired for their beauty and traditional value. On the other hand, many of Korean women complain of chest restriction. Korean skirts may give high garment pressure to the wearers because the Korean skirt-band do not resolve physical tensions in size or in stretch. This paper aims at the identification of the garment pressure caused by the Korean skirt-band and the cardiopulmonary change caused by garment pressure. The Korean skirt-band were made in 3 kinds of size, and 21 women were selected for wearing test. The garment pressure was measured in front, side, and back parts of the body. The measured cardiopulmonary parameters were vital capacity, respiratory rate, heart rate, and blood pressure. The results were as follows: 1. The smaller the size of the Korean skirt-band, the greater the garment pressure. The pressure during inspiration was significantly greater than the pressure during expiration. 2. The pressure in side part was the greatest of the three measurements and the pressure in back part was the smallest. 3. The small size of the Korean skirt-band revealed low vital capcity and great respiratory rate. 4. As the small size grement was dressed, the respiratory rate and the heart rate during walking and rest after walking were significantly high. 5. Subjects felt uncomfortable when they wore small sized garment.

• Progress in Superconductivity and Cryogenics
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• v.6 no.3
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• pp.56-61
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• 2004

An optimal cooling method for a long HTS power transmission cable was scrutinized by using theoretical models. Cooling length of HTS cable is determined by pressure range and temperature range of LN2 in the HTS cable. Results showed limitation from temperature range is stricter than that from pressure range. The well-known one-side cooling was modified to two-side cooling. It was shown that cooling length can be nearly doubled by adopting two-side cooling of the same capacity.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.435-440
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• 2009

For the effective control of a $CO_2$ air-conditioning system, the system high-side pressure algorithm, the indoor temperature algorithm, and the outdoor fan algorithm were developed. The system high-side pressure algorithm was composed of the setpoint algorithm, the reset algorithm, and the electronic expansion valve control algorithm. The indoor temperature algorithm was composed of the compressor control algorithm and the indoor fan control algorithm. These algorithms were tested by using mathematical models developed from the previous study. Results from the setpoint step change test and the disturbance test showed good control performances. Therefore, algorithms developed in this study may practically used for the control of a $CO_2$ air-conditioning system.

• Proceedings of the SAREK Conference
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• 2005.11a
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• pp.480-485
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• 2005

In the respect of the environmental protection viewpoint, the $CO_2$ may be regarded as one of the most attractive alternative refrigerants for an automotive air-conditioning system. Control methods for a $CO_2$ system should be newly developed, because properties of $CO_2$ are different compared with those of classical refrigerants. Especially, high-side pressure of a $CO_2$ system should be controlled for the effective operation of the system. In this study, intelligent control algorithms for a $CO_2$ system were developed ‘ These are a high-side pressure control algorithm and an indoor air temperature control algorithm. These algorithms were analysised by using dynamic models of a $CO_2$ system.

• Proceedings of the SAREK Conference
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• 2006.06a
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• pp.681-686
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• 2006

In order to protect the environment from the refrigerant pollution, the $CO_2$ may be regarded as one of the most attractive alternative refrigerants for an automotive air-conditioning system. Control methods for a $CO_2$ system should be different because of $CO_2's$ unique propel-ties as a refrigerant. Especially, the high-side pressure of a $CO_2$ system should be controlled for the effective operation of the system. In this study, dynamic models of a $CO_2$ air-conditioning system were developed by using experimental data. Control algorithms for a high-side pressure control and an indoor air temperature control were developed and analysed by using the dynamic simulation program of a $CO_2$ system.

• Journal of Korean Society of Water and Wastewater
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• v.29 no.1
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• pp.133-138
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• 2015

Pressure retarded osmosis (PRO) process is one of membrane processes for harvesting renewable energy by using salinity difference between feed and draw solutions. Power is generated by permeation flux multiplied by hydraulic pressure in draw side. Membrane fouling phenomena in PRO process is presumed to be less sever, but it is inevitable. Membrane fouling in PRO process decreases water permeation through membrane, resulting in significant power production decline. This study intended to investigate the effect of hydraulic pressure in PRO process on alginate induced organic fouling as high and low hydraulic pressures (6.5 bar and 12 bar) were applied for 24 h under the same initial water flux. In addition, organic fouling in draw side from the presence of foulant (sodium alginate) in draw solution was examined. As major results, hydraulic pressure was found to be not a significant factor affecting in PRO organic fouling as long as the same initial water flux is maintained, inidicating that operating PRO process with high hydraulic pressure for efficient energy harvesting will not cause severe organic fouling. In addition, flux decline was negligible from the presence of organic foulant in draw side.

• Journal of the Ergonomics Society of Korea
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• v.31 no.3
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• pp.455-461
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• 2012

The aim of this study was to investigate the appropriate elasticity of the textile material used for making women's girdle. Background: The elastic textiles have been used for making girdle. The hard type girdle gave high pressure on the body to make slim look. However, excessively high garment pressure caused negative effect to human bodies. This study studied the material giving proper garment pressure in girdle. Method: In this study five experimental girdles were made fabrics with various elasticities. The change of garment pressures and body girths were measured after subjects wearing the experimental girdles. The garment pressure was measured at 10 points. Body girths measured at abdomen, hip, and thigh. Results: The garment pressure of the commercial girdle was high at side of waistband, side femur and back gluteal fold. The experimental girdles made with high elasticity material definitely lowered garment pressure at those points. After wearing experimental girdle their abdomen and hip girths measurements were decreased. But, thigh girth was not reduced. Conclusion: The girdle made with excellent elasticity materials reduced garment pressure significantly and it made body slim as much as the commercial girdle except the thighs. Application: This study provides guideline for the developing girdle that applying optimum range of garment pressure with body slim effect.

• The KSFM Journal of Fluid Machinery
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• v.3 no.2 s.7
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• pp.36-43
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• 2000

This study presents the centrifugal compressor performance for three different vane stagger angles and wall pressure distribution within vaned diffuser channels, and is also discussed about the stability with respect to the compressor components. As the vane stagger angle decreases, the flow rate for the stall onset decreases, and higher pressure can be obtained at the low flow rate region, however, the effective operation range of the compressor decreases because of the blockage effect of the diffuser vane. Low pressure pocket within the vaned diffuser channel moves from the pressure side of leading edge to the suction side as the flow rate decreases. The compressor system stability mainly depends on that of the diffuser.