• Title/Summary/Keyword: Total-to-Total Pressure Ratio

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Comparative Study on the Pulse Wave Variables and Sasang Constitution in Diabetes Mellitus Patients and Healthy Subjects (당뇨병 환자와 건강인의 맥상과 사상체질에 관한 연구)

  • Park, Su-Jeong;Kim, Kyung-Yo;Lee, Si-Woo;Kwon, Young-Mi;Kil, Eun-Young;Joo, Jong-Cheon
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.21 no.6
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    • pp.1601-1610
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    • 2007
  • The purpose of this study was to determine whether a pulse analyzer was useful 1) to characterize the variables of pulse wave of diabetes mellitus group, compared with those of healthy subjects, and 2) to determine Sasang Constitution in diabetes mellitus group and healthy subjects. 1. The sum of pulse pressure (energy) and the ratio of systolic period area (As%), called pulse pressure-related variables, were higher in diabetes mellitus group than healthy group, while the height of dicrotic wave (h5) and the ratio of height of dicrotic wave to height of percussion wave (h5/h1), correlated with arterial compliance, were lower in diabetes mellitus group than healthy group. 2. Taeumin of diabetes mellitus group showed higher pressure-related variables than that of healthy group. 3. Soumin of diabetes mellitus group had shorter the time to dicrotic wave (t5) than that of healthy group. 4. Soyangin of diabetes mellitus group showed higher heart rates and lower values in pulse wave time-related variables, including time to dicrotic wave(t5), time to incisura (t4), total time minus time to incisura (t-t4), total time (t), width of percussion wave (w), and the ratio of width of percussion wave to total time (w/t), than that of healthy group. 5. Contact pressure (CP), sum of pulse pressure (energy), height of pre-incisura (h2), height of incisura (h4), width of percussion wave (w), time to incisura (t4), time to percussion wave (t1), variance of total time (Vt), variance of height of percussion wave(Vp) and the ratio of height of incisura to height of percussion wave (h4/h1) were used to develop the rules of Sasang Constitution Classification with about seventy five percents accuracy. These suggested that the pulse analyzer was useful to evaluate the risk degree of diabetes mellitus and to determine Sasang Constitution among either diabetes mellitus group or healthy group.

Numerical study of compression waves passing through two-continuous ducts (두 연속 덕트를 전파하는 압축파의 수치해석적 연구)

  • Kim, Hui-Dong;Heo, Nam-Geon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.22 no.6
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    • pp.823-831
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    • 1998
  • In order to investigate the impulsive noise at the exit of high-speed railway tunnel and the pressure transients inside the tunnel, numerical calculations using a Total Variation Dimishing difference scheme were applied to axisymmetric unsteady compressible flow field. Some compression wave forms were assumed to model the compression wave produced in real high-speed railway tunnel. The numerical data were extensively explored to analyze the peak over-pressure and maximum pressure gradient in the pressure wavefront. The effect of the distance and cross-sectional area ratio between two-continuous ducts on the characteristics of the pressure waves were investigated. The peak over-pressure inside the second duct decreases for the distance and cross-sectional area ratio between two tunnels to increase. The peak over-pressure and maximum pressure gradient of the pressure wavefront inside the second duct increase as the maximum pressure gradient of initial compression wave increases. The present results were qualitatively well agreed with the results of the previous shock tube experiment.

Effects of Pressure on Combustion Characteristics of Conical Flameholder

  • Yamamoto, Takeshi;Shimodaira, Kazuo;Kurosawa, Yoji
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2004.03a
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    • pp.99-105
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    • 2004
  • The effects of pressure on combustion characteristics of the conical flameholder were investigated experimentally in the pressure range from 0.11 ㎫ to 0.40 ㎫. The result shows that the total equivalence ratio of lean limit becomes lower as the combustor inlet pressure rises and NOx emission is proportional to the pressure to the 0.5th power.

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A Study on the Health and Nutritional Status of Bus Drivers in the Masan Area (마산지역 시내버스 운전자의 건강상태 및 영양소 섭취실태)

  • 윤현숙;김기련
    • Korean Journal of Community Nutrition
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    • v.7 no.3
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    • pp.316-326
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    • 2002
  • This study was carried out on 178 bus drivers in the Masan area to investigate their health and nutritional status. THe nutritional status of the subjects was surveyed using a self-administered questionnaire, and blood analyses were conducted through annual health examinations in June, 1999. The results were as fellows: About 51% were classified as normal, 33% as health-concerned, and 17% as disease-suspected. The levels of total seam cholesterol were significantly higher in the over 20 year group (194.64 $\pm$ 41.42 mg/dl) than in the under 10 year group (175,00 $\pm$ 31.33 mg/dl) with respect to the length of their driving careers. Systolic blood pressure (SBP) was significantly higher in the 51 to 60 age group than in the other groups (p < 0.05) . The total seam cholesterol increased with increasing age (p < 0.001), and SBP increased with increasing Body Mass Index (BMI) (p < 0.001). Diastolic blood pressure (DBP), total cholesterol (p < 0.01), hemoglobin (p < 0.05) and glutamate-pyruvate-aminotransferase (GPT) (p < 0.05) were significantly higher in the BMI of over 20, than in the BMI under 20. The GPT was significantly higher in the BMI over 25 than in the BMI under 25. In The mean daily energy intake was 1912.7 kcal (76.5% of the RDA) ultra the protein intake was 74.3 g (106.2% or the RDA). Compared with the recommended allowance, the energy, calcium, thiamin, and riboflavin intakes were below, and the Fe, vitamin A, vitamin C intakes were above the Korean RDA. The average carbohydrate, protein, fat ratio of energy intake was 66 : 15 : 19, respectively. The length of their driving careers had a positive correlation with their ages and total serum cholesterol levels, and their ages had a positive correlation with their blood pressures, total seam cholesterol and hemoglobin levels and BMI. Their BMI had a positive correlation with their ages, blood pressures, total serum cholesterol, hemoglobin, GPT and GOT levels. The results of this study indicate that bus drivers needed regular exercise, and control of their body weights to prevent chronic diseases, and that their health status should be monitored as the length of their driving careers and ages increase.

Relationship between Osteoporosis and Cardiovascular Risk Factors according to Sasang Constitution in Rural Wonju Cohort (원주농촌코호트에서 사상체질별 심혈관위험인자와 골다공증의 관계)

  • Song, Hak-Soo;Choi, Jae-Wan;Yu, Jun-Sang;Park, Jong-Ku
    • Journal of Sasang Constitutional Medicine
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    • v.25 no.2
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    • pp.81-97
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    • 2013
  • Objectives The purpose of this study was to investigate the relationship between osteoporosis and cardiovascular risk factors according to Sasang constitution. Methods A total of 1773 participants, over 40 years old, were examined as part of a community-based cohort in Wonju city in Gangwon province of South Korea, from June 2006 to August 2009. We measured bone mineral density by Achilles ultrasonometer, serum levels of lipids, fasting blood sugar, insulin and other cardiovascular risk factors like blood pressure and waist circumference. Constitution was verified by a Sasang constitution specialist using the results of PSSC(Phonetic System for Sasang Constitution), facial photos and a simplified Sasang constitutional questionnaire. Results The prevalence rate was 11.2% in total participants, and 10.6% in Soyangin, 10.4% in Taeeumin and 13.9% in Soeumin. In general characteristics, educational and economic property and exercise were concerned with osteoporosis. Systolic blood pressure, pulse rate and total cholesterol were significantly high in osteoporosis group. Age and menopause were the key risk factors for osteoporosis. There was a significantly high prevalence in Soeumin for osteoporosis in men alone. Low physical activity was a major risk factor for osteoporosis. Waist circumference and hip circumference had significantly high odds ratio and weight had significantly low odds ratio. By Sasang constitution, Soyangin has the negative correlation with free fatty acid, Taeeumin has the negative correlation with waist circumference, pulse rate, systolic blood pressure, total cholesterol and low density lipoprotein and Soeumin has the positive correlation with body fat amount. Conclusions Regimens on osteoporosis should be considered according to Sasang constitution. Cardiovascular diseases should be considered according to Sasang constitution. Soeumin should be cautious of osteoporosis and gain weights and reasonable amount of fat food. Soyangin had better do exercise lower body and eat little food containing triglyceride. Taeeumin had better lose weights and eat little cholesterol food.

A Study on Performance Characteristics of an Axial Compressor with the Casing Groove (케이싱 그루브가 존재하는 축류압축기의 성능특성 연구)

  • Choi, Kwang-Jin;Kim, Jin-Hyuk;Kim, Kwang-Yong
    • The KSFM Journal of Fluid Machinery
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    • v.13 no.2
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    • pp.24-29
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    • 2010
  • This paper presents a study on the performance of NASA Rotor 37 with the casing grooves based on three-dimensional numerical analysis. Reynolds-averaged Navier-Stokes equations are solved on a hexahedral grid with the shear stress transport model as a turbulence closure model. The governing equations are discretized by a finite volume method. The validation of the numerical results is performed through experimental data for the total pressure ratio and the adiabatic efficiency. The investigation for an axial compressor with a smooth casing and the casing grooves is carried out to compare the performance parameters, for example, surge margin and efficiency, etc. The surge margin is improved in the case of the casing grooves while remarkable improvement of the efficiency is not produced. The result shows that the casing groove is beneficial to expand the operating range of NASA Rotor 37.

Preliminary Design of Movable Air-Turbo Ramjet Engine Intake

  • Lee, Kyung-Jae;Kang, Sang-Hun;Lee, Yang-Ji;Yang, Soo-Seok;Lee, Dae-Sung;Kwak, Jae-Su
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2008.03a
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    • pp.480-485
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    • 2008
  • In this study, two types of ramjet intake were designed for the flight condition of Mach number 2 and 5 and numerical analysis was performed. In order to widen the flight envelope range(Mach number $2{\sim}6$), movable intake concept was applied. The central body was designed so that the capture area ratio which is one of most important factors of ramjet intake design could be adjusted. And various types of cowl and movable insert part of shell were designed in order to control throat area which could increase total pressure recovery. The numerical results showed that the designed ramjet intake could be applied in various flights Mach number.

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Study of the Flow Characteristics of Supersonic Coaxial Jets (초음속 동축제트의 유동특성에 관한 연구)

  • Lee, Gwon-Hui;Gu, Byeong-Su;Kim, Hui-Dong
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.25 no.12
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    • pp.1702-1710
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    • 2001
  • Supersonic coaxial jets are investigated numerically by using the axisymmetric, Wavier-Stokes equations which are solved using a fully implicit finite volume method. Three different kinds of coaxial nozzles are employed to understand the flow physics involved in the supersonic coaxial jets. Two convergent-divergent supersonic nozzles are designed to have the same Mach number 2.0, and used to compare the coaxial jet flows with those discharging from one constant-area nozzle. The impingement angle of the annular jets are varied. The primary pressure ratio is changed in the range from 2.0 to 10.0 and the assistant jet ratio from 1.0 to 3.0. The results obtained show that the fluctuations of the total pressure and Mach number along the jet axis are much higher in the constant-area nozzle than those in the convergent-divergent nozzles, and the constant-area nozzle lead to higher total pressure losses, compared with the convergent-divergent nozzles. The assistant jets from the annular nozzle affect the coaxial jet flows within the distance less than about ten times the nozzle throat diameter, but beyond it the coaxial jet is conical with self-similar velocity profiles. Increasing both the primary jet pressure ratio and the assistant jet pressure ratio produces a longer coaxial jet core.

Emergy Evaluation of Korean Agriculture (한국 농업의 에머지 평가)

  • Kang, Daeseok
    • Journal of Environmental Science International
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    • v.26 no.9
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    • pp.1087-1099
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    • 2017
  • Emergy methodology was used to analyze the biophysical basis of Korean agriculture and assess its sustainablility. Total yearly emergy input into Korean agriculture was $7.72{\times}10^{22}sej/yr$ in 2013. Purchased inputs were the dominant emergy source, accounting for 90.1% ($6.95{\times}10^{22}sej/yr$) of the annual input. This clearly indicates that the Korean agriculture is a modern, industrialized system that depends mostly on market goods and services derived from nonrenewable resources. The monetary equivalent of the total emergy input was 18.9 trillion \/yr, 1.5 times greater than the total production cost from farm expense surveys. Emergy return on investment of Korean agriculture was low, with an emergy yield ratio of 1.11. Korean agriculture appears to exert pressure on the environment as revealed by the high environmental loading ratio of 9.30. With very low emergy input from renewable sources (9.7%) and high environmental pressure, Korean agriculture is not sustainable, with an emergy sustainability index of 0.12. This study suggests that higher use efficiency of and lower dependence on nonrenewable purchased inputs need to be prioritized in an effort to enhance the sustainability of Korean agriculture.

The Effects of Weight Control Program on Body Composition, Blood Pressure, Serum Lipid and Self-Regulation Behavior in Obese College Women (비만중재프로그램이 비만 여대생의 신체구성, 혈압, 혈중지질 및 자기조절행위에 미치는 효과)

  • Kim, Kyung Hae;Chung, Bok Yae;Byun, Hye Sun
    • Korean Journal of Adult Nursing
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    • v.19 no.3
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    • pp.339-352
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    • 2007
  • Purpose: The purpose of this study was to investigate the effect of weight control program on body composition(body mass index and waist-hip ratio), blood pressure, serum lipids(total cholesterol, triglyceride, high density lipoprotein and low density lipoprotein) and self-regulation behavior in obese college women. Methods: Forty seven obese subjects were divided into experimental(22) and control(25) groups. The weight control program lasting 12 weeks consisted of a traffic-light diet, jumping-rope exercises, and behavior modification methods with e-mail counseling. The data were collected from 29 March to 17 September of 2004. The variables were assessed before and after intervention for 12 weeks in two groups. Then, those were repeated after a 12 week suspension of intervention in the experimental group. The data were analysed by the SPSS computer program. Results: BMI, HDL, LDL and self-regulation behavior levels showed significant differences between the experimental and control groups. While there were no significant differences in waist-hip ratio, blood pressure, total cholesterol and triglyceride. Conclusion: The weight control program had a positive effect on obese college women, and can be used to control obesity.

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