• Title/Summary/Keyword: reduced pressure

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The Change of Garment Pressure and Body Measurement by Material of Women's Girdle

  • Park, Jee-Hye;Chun, Jong-Suk
    • 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.

Experimental study on the alleviation of micro-pressure waves radiated from the tunnel exit with the slanted portals on the high-speed train operations of 300km/h (300km/h급 고속철도의 터널 미기압파 저감을 위한 경사갱구의 실험적 연구)

  • Kim, Dong-Hyeon;Min, Dong-Ho
    • Proceedings of the KSME Conference
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    • 2000.04b
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    • pp.841-846
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    • 2000
  • The compression wave produced when a high-speed train enters a tunnel propagates along the tunnel ahead of the train. The micro pressure wave related to He compression wave is a special physics Phenomena created by high-speed train-tunnel interfaces. On this work, the method for reducing the micro pressure wave is to delay the gradient of the compression wave by using aerodynamic structures. The objective of this paper is to determine the optimum angle of the slanted portal using the moving model rig. According to the results of the present study, the maximum value of micro pressure wave is reduced by 19.2% fer the $45^{\circ}$ slanted portal installed at the entrance of the tunnel and reduced by 41.9% far the $45^{\circ}$ slanted portals at the entrance and exit of the tunnel. Also it is reduced by 34.6% for the $30^{\circ}$ slanted portals installed at the entrance and exit of the tunnel.

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Development of Low Pressure Carburizing and High Pressure Gas Quenching System (뺏치식 저압침탄 고압가스냉각 시스템 개발)

  • Jang, Byoung-Lok;Han, Hyoung-Ki;Kim, Won-Bae;Dong, Sang-Keun;Kim, Han-Suck;Cho, Han-Chang
    • 한국연소학회:학술대회논문집
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    • 2005.10a
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    • pp.78-84
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    • 2005
  • The development of eco-friendly low pressure carburizing system with high pressure gas quenching (LPC_GQ, 500kg/charge) led to new stage in the fundamental case-hardening treatments. This is due to its ability to provide tighter tolerances on the carburizing process with notable reductions in distortion of the carburized and hardened workpiece. This system is characteristics by high uniformity and reproducibility of heat treatment results, absence of an intergranular oxidation layer, carburizing of complex shapes, reduced cycle time, low operating costs, simplified production, eliminate post washing, and reduced grinding costs.

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Effect of Calendering on Compressibility and Surface Properties of Sheets Made of Various Pulps (캘린더 처리가 펄프별 종이의 압축 및 표면 특성에 미치는 영향)

  • Youn Hye Jung;Lee Hak Lae;Chin Seong Min;Lee Sang Gil
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.36 no.3
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    • pp.67-73
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    • 2004
  • Effect of calendering on structural and surface properties of sheets made of various pulp was investigated. BKP, BCTMP and KOCC were used as raw materials for handsheets and sheets were calendered at the different calendering temperature and pressure conditions. Caliper, air permeability, and PPS roughness were reduced by calendering, but their effects were a little different depending on pulp type and calendering condition. Increase of density with increase of calendering Pressure was remarkable on sheet made of BCTMP or KOCC, and the effect of temperature was more significant than pressure. PPS roughness of sheet made of BCTMP or KOCC was reduced by calendering, but BKP sheet showed little reduction of roughness at higher calendering pressure. The compressibility of sheet increased logarithmetically with calendering pressure and surface compressibility of KOCC sheet was relatively higher than other pulps.

Dehumidifying Performance of Material-Saving Fin in Fin-tube Heat Exchanger (흰-관 열교환기에서 재료절감 흰의 제습특성)

  • 강희찬;김무환
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.13 no.8
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    • pp.730-738
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    • 2001
  • This work discusses the pressure droop, heat and mass transfer of the finned-tube heat exchangers having 7 mm tubes and offset strips in dehumidifying applications. It focuses on the fin material saving and the reduction of pressure drop. The experiment was conducted using three times scaled-up models to simulate the performance of the prototype. Eight kinds of fins having different strips and S shape edges were tested. the area density of the strip was a major factor and its shape and the location were secondary factors on the pressure drop, the heat and mass transfer. The reduced-area fin can almost equal the non-reduced fin in the aspect of heat and mass transfer. The strip fins proposed in the present work can considerably reduce both the pressure drop and the fin material for similar thermal load.

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The Effect of Pressure on Laminar Film Condensation along a Horizontal Plate (수평평판의 층류 막응축에서 압력의 영향)

  • Lee, Euk-Soo;Lee, Sung-Hong
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.32 no.12
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    • pp.945-953
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    • 2008
  • Laminar film condensation of saturated vapor in forced flow over a flat plate is analysed. The problem is formulated as exact boundary-layer solution and integral approximate solution. From numerical solutions of the governing equations, it is found that the energy transfer by convection and the effect of inertia term in the momentum equation in negligibly small for low pressure but quite important for high pressure. The condensate rate, liquid-vapor interfacial shear stress and local heat transfer are strongly dependent on the reduced pressure $P_r$ and the modified Jacob number Ja/Pr.

Manipulation of Microstructures of in-situ Phosphorus-Doped Poly Silicon Films deposited on Silicon Substrate Using Two Step Growth of Reduced Pressure Chemical Vapor Deposition (감압화학증착의 이단계 성장으로 실리콘 기판 위에 증착한 in-situ 인 도핑 다결정 실리콘 박막의 미세구조 조절)

  • 김홍승;심규환;이승윤;이정용;강진영
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.13 no.2
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    • pp.95-100
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    • 2000
  • For the well-controlled growing in-situ heavily phosphorus doped polycrystalline Si films directly on Si wafer by reduced pressure chemical vapor deposition, a study is made of the two step growth. When in-situ heavily phosphorus doped Si films were deposited directly on Si (100) wafer, crystal structure in the film is not unique, that is, the single crystal to polycrystalline phase transition occurs at a certain thickness. However, the well-controlled polycrtstalline Si films deposited by two step growth grew directly on Si wafers. Moreover, the two step growth, which employs crystallization of grew directly on Si wafers. Moreover, the two step growth which employs crystallization of amorphous silicon layer grown at low temperature, reveals crucial advantages in manipulating polycrystal structures of in-situ phosphorous doped silicon.

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The effect of exit opening rate on exhaust gas pressure, temperature, and engine performance (배기 출구 개도율이 배기 압력과 온도 및 엔진 성능에 미치는 영향)

  • Kim, Cheol-Jeong;Choi, Byung-Chul;Park, Kweon-Ha
    • Journal of Advanced Marine Engineering and Technology
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    • v.38 no.1
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    • pp.15-22
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    • 2014
  • Multiple devices have been installed to reduce exhaust emissions and to increase thermal efficiency. Those devices reduce the exhaust pipe opening area and increase the exhaust gas pressure. The pressure increase disturbs a gas flow and has a bad effect on the engine performance. However there is some study that NOx can be reduced with exhaust gas pressure increase. In this study an engine performance is tested with various opening ratios. The result shows that the fuel consumption rate is reduced in case of little amount of the pressure increase, and NOx is reduced with the pressure increase, while the concentration of the toxic exhaust gases are increased in the case of high back-pressure.

The Effect of Protective Socks with Functional Insoles on Plantar Foot Pressure in Diabetes Patients

  • Kim, Hyun Soo;Jung, Do Young
    • The Journal of Korean Physical Therapy
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    • v.30 no.6
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    • pp.224-228
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    • 2018
  • Purpose: The most common cause of plantar ulceration is an excessive plantar pressure in patients with peripheral neuropathy. Foot orthosis and therapeutic footwear have been used to decrease the plantar pressure and prevent the plantar ulceration in in diabetes patients. We investigated whether protective sock with functional insoles reduce plantar pressure while walking in 17 diabetes patients. Methods: An in-shoe measurement device was used to measure the peak plantar pressure while walking. Peak plantar pressure data were collected while walking under two conditions: 1) wearing diabetic sock and 2) wearing the protective sock with functional insoles. Each subject walked 3 times in 10-m corridor under three conditions, and data were collected in 3 steps in the middle of corridor with in right and left feet, respectively. Pared t-test was used to compare the peak plantar pressures in three plantar areas under these two conditions. Results: The protective sock with functional insoles significantly reduced the peak plantar pressure on the lateral rearfoot, but significantly increased the peak plantar pressure on the middle forefoot, and medial midfoot (p<0.05). However, there were not significant in medial and lateral forefoot, lateral midfoot, and medial rearfoot between diabetic sock and the protective sock conditions (p>0.05). Conclusion: The protective sock with functional insoles reduced plantar pressures in the rearfoot and supported the medial longitudinal arch. However, it is necessary to change the position of metatarsal pad in the insole design of forefoot area to prevent diabetic foot ulceration.

Hydrogen Gas Pick-Up of Al-alloy Melt During Lost Foam Casting (소실모형 주조시 알루미늄 합금 용탕의 수소 용해에 관한 연구)

  • Shin, Seung-Ryoul;Choi, Hyun-Jin;Lee, Kyong-Whoan;Lee, Zin-Hyoung
    • Journal of Korea Foundry Society
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    • v.22 no.4
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    • pp.167-173
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    • 2002
  • The hydrogen gas pick-up problem that can occur during Lost Foam Casting was investigated by reduced pressure test and practical Lost Foam Casting. The proper test pressure of reduced pressure test was determined by experiments not to use polystyrene and gas contents of the melt were calculated from density measurement results. The results showed that the hydrogen pick-up increased with the increased amount of polystyrene that was replaced by melt. The hydrogen pick-up was larger in the case of no degassed melt than that of degassed melt. So the hydrogen pick-up depended on the initial hydrogen content of the melt and the contact time of the melt with the decomposed gas phase. The mold evacuation decreased the hydrogen pick-up and increased the flow length of melt during Lost Foam Casting. And the error of calculated hydrogen pick-up was calculated by numerical method.