• Title/Summary/Keyword: Working pressure

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The Physiological Responses of Material-improved Working Clothes for Construction Site Worker (건설현장 작업복의 소재 기능성 향상에 따른 생리반응)

  • Kim, Seong-Suk;Kim, Hee-Eun
    • Fashion & Textile Research Journal
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    • v.13 no.5
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    • pp.752-758
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    • 2011
  • In this paper, experiments to develop working clothes and evaluated, including the current and material-improved working clothes in relation to physiological functionality measurement. Experiments were conducted on subjects after wearing working clothes in an climate chamber, and the thermo-physiological response, such as human body temperature, micro-climate within the clothes, blood pressure, heart rate were measured. In this manner, the physiological functionality of improved working clothes was compared with that of current working clothes and evaluated. The summary of obtained results is as follows: For physiological functionality evaluation through material-improved working clothes, P working clothes showed significantly lower rectal temperature than C working clothes. For mean skin temperature, P's skin temperature was significantly higher than C's in the second half of the experiment. P working clothes's temperature around the thighs in Micro climate was significantly lower than that of the C working clothes. Also, humidity within the clothes showed similar trends. During the exercise period, C working clothes showed higher blood pressure than P, but P showed higher heart rates than C. Also, the oxygen uptake amount was higher in C than P during the exercise period, it explains that the energy consumption amount of P working clothes was smaller than that of C working clothes. Of the subjective evaluation, for temperature sensation, workers wearing P working clothes felt cooler. For humidity, C working clothes showed more humidity. For comfort, P working clothes were better, and for sense of fatigue, workers felt less tired wearing P working clothes. From results above, we can see that physiological functionality improved in the material-improved working clothes in the working clothes for construction site workers. The improvement of working clothes through functionality improvements not only will provide personal pleasantness to constriction site workers, but will also generate efficiency and productivity improvements at construction sites. All in all, the continuous study of functionality improvements in working clothes taking into consideration the human body's physiological responses is required.

Working Point Control Characteristics of Pressure-Fed Rocket Propulsion System (가압방식 로켓추진기관시스템의 작동점 제어특성)

  • 하성업;정영석;이중엽;정태규;조상연
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2003.10a
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    • pp.31-34
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    • 2003
  • To trace the working point of pressure-fed rocket propulsion system, direct analogy model was suggested, by which propellant mass flow rate and combustion chamber pressure were calculated from propellant tank pressures, levels and flight acceleration. In this paper, the analysis of KSR-III flight test results was taken by example, and it can be described that working point transition tendency of pressure-fed rocket propulsion system can be calculated by this direct analogy model.

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Effects of the Mass of Working Fluid on the Thermal Performance of Heat Pipe with Axial Grooves (그루브형 히트파이프에서 작동유체량이 히트파이프 성능에 미치는 영향)

  • Suh, Jeong-Se;Park, Young-Jun
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.15 no.1
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    • pp.1-8
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    • 2003
  • An analytical and experimental study of the thermal performance of axial heat pipe with axial groove is conducted to determine the optimal mass of working fluid for the maximum heat transport capacity of heat pipe with axial grooves. Generally, the mass of working fluid has been fully charged by considering only a geometrical shape of axial grooves embedded in a heat pipe. When the heat pipe is operated in a steady state, the meniscus re-cession phenomena of working fluid is occurred in the evaporator region. In this work, the optimal mass of working fluid was obtained from the axial variation of capillary pressure, the radius of curvature and wetting angle of meniscus of liquid-vapor interface. Experimental results were also obtained by varying the mass of working fluid within a heat pipe, and presented for the maximum heat transport capacity corresponding to the operating temperature and the elevation of heat pipe. Finally, the analytical results of the optimal mass of working fluid were compared with those of the experimental mass of working fluid.

A Study on the Optical Properties of Diamod-Like Carbon Film (Diamond-Like Carbon 박막의 광학적 특성에 관한 연구)

  • 권도현;박성계;남승의;김형준
    • Journal of the Korean Vacuum Society
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    • v.10 no.2
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    • pp.194-200
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    • 2001
  • In this study, the optical properties of diamond-like carbon(DLC) films, which was synthesized by 13.56 MHz rf plasma enhanced chemical vapor deposition system(PECVD), were investigated. We observed the variation of the transmittance and optical band gap with respect to deposition condition. The change of the transmittance and optical band gap of the DLC films were investigated as a function of RF power, working pressure, and additional gas. The optical band gap decreased with the increase of RF power and working pressure. We could verify the bond structures change of DLC films by observing the content of hydrogen using FT-IR spectroscopy. And the addition of hydrogen and nitrogen decreased the optical band gap by the breakage of C-H bond of DLC films during the deposition.

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Properties of IZTO Thin Films Deposited on PEN Substrates with Different Working Pressures

  • Park, Jong-Chan;Kang, Seong-Jun;Yoon, Yung-Sup
    • Journal of the Korean Ceramic Society
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    • v.52 no.3
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    • pp.224-227
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    • 2015
  • In this work, the properties of Indium-Zinc-Tin-Oxide (IZTO) thin films, deposited on polyethylene naphthalate (PEN) with a $SiO_2$ buffer layer, were analyzed with different working pressures. After depositing the $SiO_2$ buffer layer on PEN substrates by plasma-enhanced chemical vapor deposition (PECVD), the IZTO thin films were deposited by RF magnetron sputtering with 1 to 7-mTorr working pressure. All the IZTO thin films show an amorphous structure, regardless of the working pressure. The best morphological, electrical, and optical properties are obtained at 3-mTorr working pressure, with a surface roughness of 2.112-nm, a sheet resistance of $8.87-{\Omega}/sq$, and a transmittance at 550-nm of 88.44%. These results indicate that IZTO thin films deposited on PEN have outstanding electrical and optical properties, and the PEN plastic substrate is a suitable material for display devices.

Transmission Loss and Back-pressure Analysis for Inner-separated Muffler (내부 분할된 단순확장관의 투과손실 및 배압 전산해석)

  • Jeong, Weuibong;Kim, Yeon Woo
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2014.10a
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    • pp.687-689
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    • 2014
  • This paper deals with the optimal muffler model by using acoustic analysis and CFD(computational fluid dynamics) analysis. The complicated muffler model could be better noise reduction performance. However, it could be worse affected to back-pressure performance by pressure drop in working fluid. High back-pressure is caused to low system efficiency. Therefore, it is important for the muffler design to consider the pressure drop. The muffler models are changed their partition plate position. Acoustic power transmission loss(TL) and pressure drop of working fluid are calculated by using computational analysis and used to build database for finding their trends. The optimal muffler model in user-interested frequency range could be selected by analyzing this database.

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Feasibility Analysis of Simulation on the Mechanical Properties of Neutron Irradiated Austenitic Stainless Steels by Cold-working (냉간가공을 통한 중성자조사된 오스테나이트 스테인리스강의 기계적물성 모사 타당성 분석)

  • Kim, Jin Weon;Kim, Yun Jae
    • Transactions of the Korean Society of Pressure Vessels and Piping
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    • v.15 no.2
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    • pp.9-18
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    • 2019
  • The objective of this study is to investigate the feasibility of simulating the mechanical properties of irradiatied austenitic stainless steels by cold-working. In this study, the tensile properties, cyclic hardening behaviors and fracture toughness of cold-worked TP316L stainless steel were compared with those of austenitic stainless steels irradiated by neutrons. It showed that cold-working can properly simulate the increase in strength and the decrease in ductility and fracture resistance of austenitic stainless steels by neutron irradiation, even though it could not perfectly simulate the microstructures of irradiated austenitic stainless steels. Also, cold-working can appropriately simulate the hardening behaviors of neutron irradiated austenitic stainless steels under monotonic and cyclic loading conditions.

Effect of Coning Combinations on Working Performances of Wavy Mechanical Face Seal (코닝 조합이 물결 프로파일이 가공된 미케니컬 페이스 실의 작동 성능에 미치는 영향)

  • Kim, Dong-Wook;Jin, Sung-Sik;Kim, Jun-Ho;Kim, Kyung-Woong
    • Tribology and Lubricants
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    • v.28 no.2
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    • pp.70-80
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    • 2012
  • Non-contact type mechanical face seals installed in mechanical systems prevent leakage of working fluid using thin working fluid film between stator and rotor. For that purpose, various kinds of surface profiles, grooves and conings have been applied on seal surfaces of stator and rotor to generate hydrodynamic and hydrostatic pressure. The thickness distribution of working fluid film is one of important factors which affect the working performances of mechanical face seal, and it is strongly affected by the surface height profiles of stator and rotor. Therefore, appropriate design of surface height profiles of stator and rotor is necessary to optimize the working performances and life of mechanical face seal. In this study, numerical analysis using finite volume method was conducted to estimate the working performances of wavy mechanical face seals which have 36 coning combinations. As results, minimum thickness of working fluid film, leakage volume of working fluid and friction torque in static equilibrium condition of mechanical face seal, and stiffness of working fluid film were obtained. The results show that the working performances of mechanical face seal were affected by the coning combinations which can change the thickness distribution of working fluid film and pressure distribution in sealing region of mechanical face seal.

Nursing Interventions Classification(NIC) Use in Korea : Oriental Medicine Hospitals and General Hospitals (간호중재분류(NIC)에 근거한 간호중재수행분석 II -한방병동과 일반병동 간호사를 중심으로-)

  • 염영희;김성실;김인숙;박원숙;김은주
    • Journal of Korean Academy of Nursing
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    • v.29 no.4
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    • pp.802-816
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    • 1999
  • The purposes of this research were to identify nursing interventions performed by Korean nurses and to compare the interventions performed by nurses working in the oriental medicine hospitals and with those performed by nurses working in the general hospitals. The samples consisted of 144 Korean nurses working in three hospitals, 70 nurses working in the oriental medicine hospitals and 74 nurses working in the general hospitals. The Nursing Interventions Classification (NIC) Use Questionnaire developed by the Iowa Intervention Project team was translated to Korean and verified using the method of back-translation. The questionnaire consists of 433 intervention labels and definition. Thirteen interventions were used at least daily by nurses working in the oriental medicine hospitals, while twenty-one interventions were used at least daily by nurses working in the general hospitals. The most frequently used interventions by nurses working in the oriental medicine hospitals were Documentation, Shift Report Vital Signs Monitoring, Pressure Ulcer Prevention, Positioning, Fall Prevention, Exercise Promotion, Intravenous (IV) Therapy, Pressure Ulcer care, and Bed Rest Care in that crder. For nurses working in the general hospitals the most frequent intervention was Analgesic Administration, followed by the interventions of Medication Administration : Parenteral and Intravenous Therapy (IV) Therapy, Documentation, Intravenous(IV) Insertion, Shift Report, Fall Prevention, Vital Signs Monitoring, Medication Adnninistraction : and, Fluid Monitoring, and Medication Maragement in that order. The interventions performed least often by nurses working in the oriental medicine hospitals were Hemodialysis Therapy and Bleeding Reduction : Antepartum Uterus, while the interventions performed least often by nurses working in the general hospitals were Rape Trauma Treatment and Contact Lens Care. The nurses working in the oriental medicine hospitals performed the interventions in the Physiological : Complex domain significantly more often than the nurses working in the general hospitals, while the nurses working in the general hospitals performed the intervention in the Behavior domain significantly more often than the nurses working in the oriental medicine hospitals. This study suggests that further study will be needed to developed and validate more interventions sensitive to Korean culture.

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Theoretical Analysis of the Pressure Drop in Loop Heat Pipe by Sintered Porous Wick Structure (다공성소결윅구조에 따른 루프 히트파이프에서 압력손실의 이론적 분석)

  • Lee, K.W.;Lee, W.H.;Park, K.H.;Lee, K.J.;Chun, W.P.;Ihn, H.M.
    • Proceedings of the KSME Conference
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    • 2004.04a
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    • pp.1225-1230
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    • 2004
  • In this paper, the pressure drops were investigated according to the sintered porous wick structure in loop heat pipe(LHP) by theoretical analysis. LHP has the wick only in evaporator for the circulation of working fluid, so utilizes porous wick structure which pore diameter is very small for large capillary force. This paper investigates the effects of different parameters on the pressure drops of the LHP such as particle diameter of sintered porous wick, wick porosity, vapor line diameter, thickness of wick and heating capacity. Working fluid is water and the material of sintered porous wick is copper. According to the these different parameters, capillary pressure, pressure drop in wick were analized by theoretical design method of LHP.

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