• 제목/요약/키워드: rate effects

검색결과 17,037건 처리시간 0.042초

Effects of Massage on Musculoskeletal Ultrasound and Heart Rate Variability in Middle Age Women of Office Worker

  • Yon, Jung-Min;Lee, Og-Kyoung
    • 대한의생명과학회지
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    • 제19권1호
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    • pp.55-60
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    • 2013
  • This study was to know the effects of massage on the back region in order to reduce stress in middle age women. To investigate the effects of massage to the stress levels of middle aged women, we evaluated blood pressure (BP), heart rate variability (HRV), and ultrasonography before and after back massage. The blood pressure after massage was reduced when compared to that of pre-massage. The HRV spectrum analysis was used Frequency domain analysis such as Mean HRV, normalized low frequency (norm LF), norm high frequency (norm HF), and LF/HF ratio. Post-massage BP tended to be low, but not statistical significant. After Massage, the Mean HRV, norm LF, and LF/HF ratio were significantly reduced, while norm HF was significantly increased as compared with pre-massage. The muscle layer and fat layer were significantly diminished by massage. The study was suggested that massage may be an effective treatment for relief of stress.

A Study on the Effects of System Pressure on Heat and Mass Transfer Rates of an Air Cooler

  • Jung, Hyung-Ho
    • Journal of Mechanical Science and Technology
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    • 제16권5호
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    • pp.696-702
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    • 2002
  • In the present paper, the effects of inlet pressure on the heat and mass transfer rates of an air cooler are numerically predicted by a local analysis method. The pressures of the moist air vary from 2 to 4 bars. The psychrometric properties such as dew point temperature, relative humidity and humidity ratio are employed to treat the condensing water vapor in the moist air when the surface temperatures are dropped below the dew point. The effects of the inlet pressures on the heat transfer rate, the dew point temperature, the rate of condensed water, the outlet temperature of air and cooling water are calculated. The condensation process of water vapor is discussed in detail. The results of present calculations are compared with the test data and shows good agreements.

Fast(submillisecond) Switching of Nematic Liquid Crystals and Effects of Dielectric Dispersion; Theory and Experiment

  • Shiyanovskii, Sergij V.;Golovin, Andrii B.;Yin, Ye;Lavrentovich, Oleg D.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.I
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    • pp.181-186
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    • 2005
  • We demonstrate that the finite rate of dielectric relaxation in liquid crystals which has been ignored previously causes profound effects in the fast dielectric reorientation of the director. The phenomenon is relevant for submillisecond switching of the director when the switching rate approaches the rate of dielectric relaxation through the reorientation of the molecular dipoles. A submillisecond switching ($15-400\;{\mu}s$ for an optical retardation shift $0.3-2.2\;{\mu}m$ in $10-15\;{\mu}m$ thick cells) is demonstrated for dual frequency nematic cells with high pretilt that maximizes the dielectric torque acting on the director. We propose the theory of dielectric response in which the electric displacement depends not only on the present (as in the standard theory) but also on the past values of electric field and director. We design an experiment in which the standard "instantaneous" model and our model predict effects of opposite signs; the experimental data support the latter model.

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Effects of Steroid Hormones on Collagen Biosynthesis in Rat Aorta and Uterus

  • 민병무;김왕국;정동균
    • 대한치과의사협회지
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    • 제19권7호통권146호
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    • pp.609-614
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    • 1981
  • Effects of steroid hormones on the collagen biosynthesis in aorta and uterus were studied with ovariectomized Sprague-Dawley rats. Effects of administration of hormones, such as estrogen, testosterone and prednisolone, to the ovariectomized animals were studied, comparing with the control. Each group was injected with ³H-proline and sacrificed, followed by removals of aorta and uterus. Separations and quantitative analyses of proline and hydroxyproline were performed by means of thin layer chromatography; and radioactivities of the separated amino acids were assayed by liquid scintillation counter. Normally the incorporation of ³H-proline into hydroxyproline was greater in uterus than in aorta, and collagen turnover rate of uterus was observed rapid as well than that of aorta. In the two tissues from ovariectomized rats, the incorporation rate of ³H-proline into hydroxypoline was markedly decreased than that of the former. Changes in the turnover rate of collagen in these tissues were not observed. Decrease in ³H-proline incorporation into collagen in ovariectomized rats was markedly antagonized by estrogen, but not influenced by prednisolone in the tissues tested.

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Effects of Non-absorbable Gases in the Absorption of Water Vapor by Aqueous LiBr Solution Film on Horizontal Tube Banks

  • Kwon, Ky-Seok;Kim, Byong-Joo
    • International Journal of Air-Conditioning and Refrigeration
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    • 제9권2호
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    • pp.19-27
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    • 2001
  • In the present study, the effects of film Reynolds number (60∼200) and volumetric content of non-absorbable gases (0∼10%) in water vapor on the absorption process of aqueous LiBr solution were investigated experimentally. The formation of solution film on the horizontal tubes of six rows was observed to be complete for Re>100. Transition film Reynolds number was found to exist above which the Nusselt number and Schmidt number diminishes with solution flow rate. As the concentration of non-absorbable gases increased, mass transfer rate decreased more seriously than heat transfer rate did. the degradation effects of non-absorbable gases seemed to be significant especially when small amount of non-absorbable gases was introduced to the pure water vapor.

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항염 및 해열효과에 미치는 Ibuprofen과 Prednisolone의 약 상호 작용 (Drug Interactions of Ibuprofen and Prednisolone in Antiinflammatory and Antipyretic Effects)

  • 강영자;조윤성
    • 약학회지
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    • 제25권3호
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    • pp.109-114
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    • 1981
  • The authors investigated drug interaction of ibuprofen and prednisolone in antiinflammatory and antipyretic activities. We have found significant differences of the antiinflammatory and antipyretic activities between single and concurrent administration of ibuprofen and prednisolone, using Sprague-Dawley Strain rats, carrageenin as a phlogistic agent and brewer's yeast as a fever inducing agent. 1) Ibuprofen(20mg/kg) was administered to the rats orally and resulted in significant reduction of (31.70 %) the swelling of rat paw induced by carrageenin, 2) prednisolone (9mg/kg) showed significant reduction of (45.76%) the swelling, 3) concurrent administration of ibuprofen (20mg/kg) and prednisolone (9mg/kg) also reduced (57.40%) the swelling. In ibuprofen (125mg/kg) administration, the inhibition rate of edema was 39.32% and in prednisolone (1mg/kg) administration, the rate was 39.04%. In concurrent administration of ibuprofen (125mg/kg) and prednisolone (1mg/kg), the inhibition rate of edema was 63.09%. Concurrent administration of ibuprofen and prednisolone showed more anti-inflammatory effects than single administration of ibuprofen and prednisolone respectively. Prednisolone itself did not show antipyretic effect, but concurrent administration of ibuprofen and prednisolone showed more antipyretic effects than ibuprofen single administratron.

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수평관군에서 리튬브로마이드 수용액 막의 수증기 흡수과정에 대한 비흡수가스의 영향 (Effects of non-absorbable gases in the absorption process of water vapor Into the Lithium Bromide-water solution film on horizontal tube bank)

  • 김병주;권기석
    • 설비공학논문집
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    • 제12권2호
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    • pp.218-225
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    • 2000
  • In the present study, the effects of film Reynolds number (60∼200) and volumetric content of non-absorbable gases (0∼10%) in water vapor on the absorption process of aqueous LiBr solution were investigated experimentally. The formation of solution film on the horizontal tubes of six rows were observed to be complete for Re>100. Transition film Reynolds number were found to exist above which the Nusselt number and Schmidt number diminishes with solution flow rate. As the concentration of non-absorbable gases increased, mass transfer rate decreased more seriously than heat transfer rate did. The degradation effects of non-absorbable gases seemed to be significant especially when small amount of non-absorbable gases were introduced to the pure water vapor.

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Equity across Generations and Uncertainty within a Generation: A Welfare Analysis of the National Pension System

  • KWON, KYOOHO
    • KDI Journal of Economic Policy
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    • 제41권2호
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    • pp.1-39
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    • 2019
  • This paper utilizes a life-cycle overlapping-generations model to quantify the welfare effects of plans to postpone the depletion of the National Pension Fund. In order for the model to incorporate the rapidly changing demographic structure of Korea fully, we build and calibrate a model in transition directly. The model is considered suitable for analyzing the effects of demographic changes on the Korean economy and the effects of plans to change the National Pension System. According to a simulation of the model, to postpone the depletion of the National Pension Fund for 30 years, the premium rate must be increased to 18.3% from the current rate of 9%. By postponing the depletion of the fund reserve, young and future generations gain significantly at the expense of the older generations. The simulation results should be, however, interpreted as meaning that the current system is unjustifiably partial to the older generations. Moreover, given the current premium rate, it is desirable to strengthen the income-redistribution function of the National Pension System.

Igniter and Thickness Effects on Upward Flame Spread

  • J.Q. Quintiere;Lee, C.H.
    • 한국화재소방학회:학술대회논문집
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    • 한국화재소방학회 1997년도 International Symposium on Fire Science and Technology
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    • pp.154-161
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    • 1997
  • Several studies have developed upward flame spread models which use somewhat different features. However, the models have not considered the transient effects of the igniter and the burning rate. Thus, the objective of this study is to examine a generalized upward flame spread model which includes these effects. We shall compare the results with results from simpler models used in the past in order to examine the importance of the simplifying assumptions. We compare these results using PMMA, and we also include experimental results for comparison. The results of the comparison indicate that flame velocity depends on the thermal properties of a material, the specific model for flame length and transient burning rate, as well as other variables including the heat flux by igniter and flame itself. The results from the generalized upward flame spread model can provide a prediction of flame velocity, flame and pyrolysis height, burnout time and position, and rate of energy output as a function of time.

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Effects of various freezing containers for vitrification freezing on mouse oogenesis

  • Kim, Ji Chul;Kim, Jae Myeoung;Seo, Byoung Boo
    • Journal of Animal Science and Technology
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    • 제58권3호
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    • pp.13.1-13.7
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    • 2016
  • Background: In the present study, various freezing containers were tested for mouse embryos of respective developmental stages; embryos were vitrified and then their survival rate and developmental rate were monitored. Mouse two cell, 8 cell, and blastula stage embryos underwent vitrification freezing-thawing and then their recovery rate, survival rate, development rate, and hatching rate were investigated. Methods: EM-grid, OPS, and cryo-loop were utilized for vitrification freezing-thawing of mouse embryos. Results: It was found that recovery rate and survival rate were higher in the group of cryo-loop compared to those of EM-grid (p < 0.05). Embryonic development rate, two cell embryos to blastocyst, as well as hatching rate were higher in the control group compared to the EM-grid group and OPS group (p < 0.05), yet no difference was noted between the control group and cryo-loop group. Development rate and hatching rate of eight cell morulae and blastocysts were all lower in the treatment groups than the control group whilst hatching rate of blastocysts was higher in the control group compared to the groups of EM-grid and OPS (p < 0.05); although the cryo-loop group was shown to be slightly higher than other groups, it was not statistically significant. Conclusions: In the study, we investigate effects of freezing containers on vitrified embryos of respective developmental stages; it was demonstrated that higher developmental rate was shown in more progressed (or developed) embryos with more blastomeres. There was however, no difference in embryonic development rate was shown amongst containers. Taken together, further additional studies are warranted with regards to 1) manipulation techniques of embryos for various vitrification freezing containers and 2) preventive measures against contamination via liquid nitrogen.