• 제목/요약/키워드: pressure effects

검색결과 7,977건 처리시간 0.031초

The Effects of the Upright Body Type Exercise Program on Foot Plantar Pressure of Archers

  • Kim, Dong-Kuk;Lee, Joong-Sook
    • 한국운동역학회지
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    • 제26권3호
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    • pp.285-292
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    • 2016
  • Objective: This study collected data on muscle fatigue and ground reaction force during walking to provide a basis for development of custom-fitted outdoor walking shoes. The study analyzed an upright body exercise program using spine stabilization technique to determine the effect on foot plantar pressure in archers, demonstrate the effectiveness of upright body exercise, and develop a new, effective, and efficient training program. Method: A 12-week upright body exercise program was evaluated for the effect on plantar pressure in archers. Ten prize-winning archers (3 men, 7 women) in B metropolitan city, each with ${\geq}10years$ of experience, were given an explanation of the content and purpose of the program, and provided informed consent. Upright body exercise was performed 3 times a week for 12 weeks. A resistive pressure sensor was used to measure foot plantar pressure distribution and analyze quantitative information on variation in postural stability and weight shifting in dynamic balance during shooting, as well as plantar pressure in static balance with the eyes open and closed. Results: There were no significant differences in foot plantar pressure before and after participation in the exercise program. There was no statistically significant difference in foot plantar pressure in static balance with the eyes open or closed, or in foot plantar pressure in dynamic balance during shooting. Conclusion: An upright body exercise program had positive effects on foot plantar pressure in static and dynamic balance in archers by reducing body sway and physical imbalance during shooting and with eyes closed. This program is expected to help archers improve their posture and psychological state, and thereby improve performance.

사궁산(莎芎散)이 실험동물(實驗動物)의 지혈(止血), 뇌압(腦壓), 혈압(血壓) 및 심혈관계(心血管系)에 미치는 영향(影響) (Effects of Sagungsan on the Hemostasis, Intracranial Pressure, Blood Pressure and Cardiovascular System in Expreimental Animals)

  • 안일회;박영순;김세길
    • 대한한방내과학회지
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    • 제15권1호
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    • pp.80-98
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    • 1994
  • According to the original documents, Sagungsan is considered as an effective drug for controlling the hypertensive epistaxis induced by tension of autonomic nerve and it's hyperfunction. The present experiment was designed to understand the effect of Sagungsan extract on the hemostatic action, intracranial pressure, blood pressure and cardiovascular system in experimental animals. And thus the bleeding time, prothrombin time, capillary dilation, blood pressure, Intracranial pressure, and enzymatic analysis of the ATPase activities were studied. The result obtained here were as followings: 1. Sagungsan water extract reduced the bleeding time in mouse, and prolonged the prothrombin time in rabbits. 2. The drug extract increased the tail volume by capillary dilation in rats. 3. The drug extract inhibited the increase of intracranial pressure and arterial blood pressure in rabbits. 4. At the early time, the increase of arterial blood pressure by the drug extract significantly inhibited by pretreated atropin and regitine in rabbits. 5. The drug extract relaxed the smooth muscle by stimulating the Mg2+-Ca2+-ATPase activities of gastric sarcoplasmic reticulum isolated from rabbit stomach. 6. The drug extract stimulated the heart contraction by inhibiting the $Mg^{2+}-Ca^{2+}-ATPase$ activities of cardiac sarcoplasmic reticulum isolated from rabbit heart. The inhibitory mechanism was reversible and noncompatitive. 7. The drug extract increased the hepatic blood volume by stimulating the hepatic total ATPase activities and hepatic metabolism. 8. The drug extract acted as a tranquilizer by inhibiting the neural Na+-K+-ATPase activity. According to the results, Sagungsan water extract dilated the capillaries, stimulated the heart beat, and thus increased the blood flow with decreasing the intracranial pressure and blood pressure. These effects stanches the epistaxis collectively.

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半圓周形 윤활홈을 갖는 저어널 베어링의 熱效果에 관한 연구 (A Study of Thermal Effects for a Half-Circumferential Grooved Journal Bearing)

  • Chun, Sang-Myung;Lalas, Demetrius P.
    • Tribology and Lubricants
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    • 제6권1호
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    • pp.36-51
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    • 1990
  • A parametric study of the thermal effects of a half-circumferential grooved journal bearings under aligned and misaligned conditions has been carried out by solving numerically the coupled Reynolds and energy equation system. Five different sets of boundary conditions for the energy equation have been used which include mixing between recirculating oil and inlet oil and a contraction ratio for the cavitation region. The effects of changes of the inlet oil temperature and pressure, the wall temperature and the L/D ratio have also been examined. For the range of parameters found in internal combustion engines, the mixing effectiveness at the groove and the resulting final mixture temperature have been found to be as important as the wall temperature and the heat transfer rate. The variability of the temperature, though, has been shown to smooth out the peaks of both pressure and friction during misaligned condition Distributions of friction and pressure in the oil are also examined which may be useful in attempts to reduce friction without reducing load. Results for an axial grooved bearing are also presentsed for comparision purpose.

흡기중의 수증기분압과 점화시기 및 연료 변화에 따른 스파크 점화기관의 화염 전파 특성 분석 (An Experimental Analysis of the Effects of Water Vapor Partial Pressure in Inlet Air, Spark Advance and Fuel Type on the Flame Propagation in a Spark Ingnition Engine)

  • 이택헌;전광민
    • 한국자동차공학회논문집
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    • 제6권5호
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    • pp.191-198
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    • 1998
  • In this study, the effects of water vapor in inlet air, spark advance and fuel type in the spark ignition engine were investigated through the experiments of combustion and flame arriving pattern analysis using ionization probe. The results of flame propagation experiment using ionization probe show that the flame which ignited from spark plug located at the center of the combustion chamber propagated faster in exhaust side than in intake side due to the mixture flow motion inducted into combustion chamber from intake tumble port at all conditions. And as the partial vapor pressure increased, the flame propagation became slower in all direction. Especially effects were greater for intake side than the exhaust side.

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YSZ/CeO$_2$/Ni 에서 산소 분압의 완층충 특성에 대한 영향 (The effects of $O_2$ partial pressure on the property of buffer layer in YSZ/CeO$_2$/Ni)

  • 이규한;염도준
    • 한국초전도학회:학술대회논문집
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    • 한국초전도학회 1999년도 High Temperature Superconductivity Vol.IX
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    • pp.326-328
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    • 1999
  • We investigated the effects of residual gas partial pressure on the property of a CeO$_2$ buffer layer on a textured Ni tape, where the buffer layer was deposited by e-beam evaporation. The oxygen partial pressure were varied from 10$^{-7}$ to 10$^{-4}$ Torr. we also changed the surface condition for the surface oxygenation. We'll describe the detail of the resultant textures of the buffer layers and effects of YBCO growth on them

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속도의 영향에 따른 3차원 거친 표면의 혼합윤활해석 (Effect of Sliding Velocity on 3D Rough Surface in Mixed Lubrication Regime)

  • 임동진;문석만;조용주
    • Tribology and Lubricants
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    • 제29권1호
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    • pp.27-32
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    • 2013
  • This study examined the effects of surface roughness in the mixed lubrication regime of smooth and rough surfaces for roller bearings. The average flow model was adopted for interaction between the flow rheology of the lubricant and the surface roughness. The average Reynolds equation and related flow factor that describes the coupled effects of surface roughness and flow rheology, the viscosity-pressure and density-pressure equations, the elastic deformation equation, and the force balance equation were solved simultaneously. The results showed that the effects of surface roughness on the film thickness and pressure distribution should be considered, especially in elastohydrodynamic lubrication contact problems.

경사진 배플이 있는 셀측의 수치적 해석 (Numerical prediction of shell-side flow with inclined baffles)

  • 김은필
    • Journal of Advanced Marine Engineering and Technology
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    • 제24권5호
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    • pp.119-124
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    • 2000
  • A finite element method is applied to investigate the characteristics of the fluid flow and heat transfer performance in a channel in terms of the various effects of baffle cuts, baffle angles, and leakages. The results show that the decrease of a baffle cut gives a good heat transfer enhancement. However, it also increases pressure drop. In the case of an inclined baffle, the result shows that the pressure drop decreases with a reasonable heat transfer performance. But a steeply inclined baffle gives adverse effects on the performance of the channel. The clearances between baffle-to-shell and tube-to-baffle affect the overall performance. The effects of these parameters are discussed in details.

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항공기용 연료계통 압력조절밸브의 FMEA를 적용한 신뢰성 설계 (Reliability Design Using FMEA for Pressure Control Regulator of Aircraft Fuel System)

  • 배보영;이재우;변영환
    • 한국항공운항학회지
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    • 제17권1호
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    • pp.24-28
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    • 2009
  • The reliability assessment is performed for Pressure Control Regulator of Aircraft Fuel System using reliability procedure which consists of the reliability analysis and the Failure Modes and Effects Analysis(FMEA). The target reliability as MTBF(Mean Time Between Failure) is set to 5000hr. During the reliability analysis process, the system is categorized by Work Breakdown Structure(WBS) up to level 3, and a reliability structure is defined by schematics of the system. Since the components and parts that have been collected through EPRD/NPRD. The predicted reliability to meet mission requirements and operating conditions is estimated as 4375.9hr. To accomplish the target reliability, the components and parts with high RPN have been identified and changed by analyzing the potential failure modes and effects. By changing the configuration design of components and parts with high-risk, the design is satisfied target reliability.

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초임계 압력상태에서 기체수소/액체산소 국소화염구조 해석 (Analysis for Local Structure of Gaseous Hydrogen/liquid Oxygen Flame at Supercritical Pressures)

  • 김태훈;김성구;김용모
    • 한국분무공학회지
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    • 제15권4호
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    • pp.182-188
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    • 2010
  • Significant real fluid behaviors including rapid property changes take place where high pressure combustion devices such as rocket engines. The flamelet model is the reliable approach to account for the real fluid effects. In the present study, the flamelet equations are extended to treat the general fluids over transcritical and supercritical states. The real fluid flamelet model is carried out for the gaseous hydrogen and cryogenic liquid oxygen flames at the wide range of thermodynamic conditions. Based on numerical results, the precise discussions are made for effects of real fluid, pressure, and differential diffusion on the local flame structure.

후두 수직운동이 성대에 미치는 영향 (The Effects of Vertical Laryngeal Movements on the Vocal Folds)

  • 홍기환;김현기
    • 음성과학
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    • 제1권
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    • pp.261-274
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    • 1997
  • In spite of the presumed importance of the strap muscles on laryngeal valving and speech production, there is little research concerning the physiological role and the functional differences among the strap muscles. Generally, the strap muscles have been shown to cause a decrease in the fundamental frequency(Fo) of phonation during contraction. In this study, an in vivo canine laryngeal model was used to show the effects of strap muscles on the laryngeal function by measuring the Fo, subglottal pressure, vocal intensity, vocal fold length, cricothyroid distance, and vertical laryngeal movement. Results demonstrated that the contraction of sternohyoid and sternothyroid muscles corresponded to a rise in subglottal pressure, shortened cricothyroid distance, lengthened vocal fold, and raised Fo and vocal intensity. The thyrohyoid muscle corresponded to lowered subglottal pressure, widened cricothyroid distance, shortened vocal fold, and lowered Fo and vocal intensity. It was postulated that the mechanism of altering Fa and other variables after stimulation of the strap muscles is due to the effects of laryngotracheal pulling, upward or downward, and laryngotracheal forward bending, by the external forces during strap muscle contraction.

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