• 제목/요약/키워드: Total Pressure

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용융염계에서 자전연소합성법에 의한 α-Si3N4분말의 제조 - 2. 반응물의 증가 (Preparation of α-Si3N4 Powder in Reaction System Containing Molten Salt by SHS - Part 2. Scale-Up)

  • 윤기석;양범석;박영철;원창환
    • 한국세라믹학회지
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    • 제41권9호
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    • pp.703-708
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    • 2004
  • 앞선 논문 분말의 제조에서 정립한 $\alpha$-Si$_3$N$_4$ 분말의 제조를 위한 최적의 조성에서 반응 혼합물의 양에 따른 압력 및 생성물의 변화를 관찰하였다. 5L 반응기 내에서 반응 혼합물의 양이 100g일 때 필요한 최저 $N_2$ 압력은 60atm이었다. 그러나 반응 혼합물의 양이 200g 이상일 때부터 반응기 내부의 압력 증가로 인해 반응은 완료될 수 없었으며, 혼합물이 증가할수록 반응율은 직선적으로 감소하였다. 반응물의 양이 증가할수록 최초 반응기 내부의 $N_2$압력을 감소시킴으로써 반응을 완료시킬 수 있었으며, 500g일 때 초기 $N_2$ 압력을 약 20atm까지 감소시킴으로써 반응은 완료될 수 있었다. 반응이 중간에 멈추는 원인은 반응기 내부의 압력 증가로 인해 기화되지 못한 채 혼합물 안에 존재한 NH$_4$Cl때문인 것으로 밝혀졌다.

The Relationships Among Body Fat Distribution, Blood Pressure, Blood Lipids and Exercise in Healthy Men and Women

  • 최미자
    • 동아시아식생활학회지
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    • 제3권2호
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    • pp.29-40
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    • 1993
  • A variety of studies show that a centraized rather than a generalized pattern of subcutaneous fat distribution is more directly associated with disorers of carbohydrate and lipid metabolism, as possibly hypertension, This study was an attempt to observe the relationship of body fat distribution, blood lipids, blood pressure and exercise in 85 healthy men and women. Within this group there was a gradation of fat distribution progressing from LBSO and UBSO defined on the basis of WHR. This paper reports the relationship of body fat distribution defined by WHR to plasma glucose, lipids, blood pressure, and exercise in this population. Although the obesity indices(RBW and BMI) were slightly higher in the UBSO group, significant differences existed between UBSO and LBSO groups with respect to WHR blood pressure, and total cholesterol concentration in female. WHR values were substantially different and this was primarily due to greater degrees of differences in waist as opposed to hips circum ference. Although no significant differences existed between UBSO and LBSO groups with respect to age, body weight, and hips circumference, energy intake, total cholesterol, LDL-cholesterol and WHR values were substantially different in male. Positive, significant correlations were found between WHR and both systolic and diastolic blood pressure and between WHR and the total plasma cholesterol concentration and age. When 26 pairs of exercise and nonexercise groups were matched according to sex, age and body weight, blood pressure and blood lipids were significantly lower in the exercise groups than those in the nonexercise groups. In conclusion, these findings suggest that an altered blood lipid profiles will manifast in men and women with upper body obese. Furthermore these findings suggest that exercise and physical activity may be beneficial for controlling blood lipids and blood pressure in healthy adults.

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국민학교 학동의 혈압에 관련된 요인분석 (Risk Factors in Relation to Blood Pressure in Schoolchildren)

  • 이동수;이경수;강복수
    • Journal of Yeungnam Medical Science
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    • 제10권2호
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    • pp.345-359
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    • 1993
  • 대구시내 1개 국민학교 4학년 284명(남아 144명, 여아 140명)을 대상으로, 1992년 5월에 일반적인 특성을 조사하였고, 체격, 체지방 및 혈압을 측정하였으며, 혈액의 생화학적 검사를 실시하여 혈압과 관련된 요인을 분석하였다. 대상자의 평균 수축기 혈압은 103.5mmHg였으며, 남아가 104.1mmHg, 여아가 102.9mmHg로 남아가 약간 높게 나타났으며, 평균 확장기 혈압은 67.1mmHg이고, 남아가 66.6mmHg, 여아가 67.5mmHg로 여아가 약간 높았다. 수축기 및 확장기 혈압을 종속변수로 총콜레스테롤, 고밀도 지단백 콜레스테롤, 저밀도 지단백 콜레스테롤, 중성지방, 총단백질, 요산, 혈당, R$\ddot{o}$hrer지수, 체지방 비율, 체지방 무게 및 제지방체중을 독립변수로 하여 상관관계와 중회귀분석을 실시하였다. 수축기 및 확장기혈압과 독립변수들과의 상관관계를 성별에 따라 분석한 결과 남아의 수축기혈압은 신장, 체중, R$\ddot{o}$hrer지수, 제지방 체중, 체지방 무게 및 중성지방과 유의한 상관관계가 있었으며(p<0.01). 여아의 수축기혈압은 신장, 체중, 제지방체중 및 요산과 유의한 상관관계가 있었다(p<0.01). 남아의 확장기혈압은 체중, R$\ddot{o}$hrer지수 및 제지방체중과 유의한 상관관계가 있었으며(p<0.01). 여아의 확장기혈압은 체중, 제지방체중(p<0.01), 신장, 체지방무게 및 총단백질(p<0.05)과 유의한 상관관계가 있었다. 수축기 혈압을 종속변수로 한 중회귀분석에서 남아는 R$\ddot{o}$hrer지수와 sodium이 유의한 변수였고, 여아는 요산, R$\ddot{o}$hrer지수 및 체지방 비율이 유의한 변수였다. 확장기 혈압에서 남아는 R$\ddot{o}$hrer지수가 유의한 변수였고, 여아는 총단백질이 유의한 변수였다. 이상의 결과로 보아 소아의 혈압에 영향을 미치는 인자로는 R$\ddot{o}$hrer지수, sodium, 요산, 총단백질 및 체지방 비율 이었고, 그 중 R$\ddot{o}$hrer지수가 가장 중요한 요인으로 인정되었다. 따라서 고혈압 발생을 예방하기 위해서는 비만, 식이 및 이와 관련된 생활양식의 개선과 이에 대한 보건교육이 요망된다.

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Expansion of Dusty H II Regions and Its Impact on Disruption of Molecular Clouds

  • Kim, Jeong-Gyu;Kim, Woong-Tae;Ostriker, Eve
    • 천문학회보
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    • 제40권1호
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    • pp.58.3-59
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    • 2015
  • Dynamical expansion of H II regions plays a key role in dispersing surrounding gas and therefore in limiting the efficiency of star formation in molecular clouds. We use analytic methods and numerical simulations to explore expansions of spherical dusty H II regions, taking into account the effects of direct radiation pressure, gas pressure, and total gravity of the gas and stars. Simulations show that the structure of the ionized zone closely follows Draine (2011)'s static equilibrium model in which radiation pressure acting on gas and dust grains balances the gas pressure gradient. Strong radiation pressure creates a central cavity and a compressed shell at the ionized boundary. We analytically solve for the temporal evolution of a thin shell, finding a good agreement with the numerical experiments. We estimate the minimum star formation efficiency required for a cloud of given mass and size to be destroyed by an HII region expansion. We find that typical giant molecular clouds in the Milky Way can be destroyed by the gas-pressure driven expansion of an H II region, requiring an efficiency of less than a few percent. On the other hand, more dense cluster-forming clouds in starburst environments can be destroyed by the radiation pressure driven expansion, with an efficiency of more than ~30 percent that increases with the mean surface density, independent of the total (gas+stars) mass. The time scale of the expansion is always smaller than the dynamical time scale of the cloud, suggesting that H II regions are likely to be a dominant feedback process in protoclusters before supernova explosions occurs.

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과잉간극수압 발생을 고려한 중력식 안벽구조물의 동적해석 (Dynamic Analysis of Gravity Quay Wall Considering Development of Excess Pore Pressure in Backfill Soil)

  • 유무성;황재익;김성렬
    • 한국해양공학회지
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    • 제24권5호
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    • pp.39-47
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    • 2010
  • In this paper, a total stress analysis method for gravity quay walls is suggested. The method can evaluate the displacement of the quay walls considering the effect of excess pore pressure developed in backfill soils. This method changes the stiffness of backfill soils according to the expected magnitude of the excess pore pressure. For practical application, evaluation methods are suggested for determining the excess pore pressure ratio developed in the backfill soils and the backfill stiffness that corresponds to the excess pore pressure ratio. This method is important in practical applications because the displacement of the quay walls can be evaluated by using only the basic input properties in the total stress analysis. The applicability of the suggested method was verified by comparing the results of the analysis with the results of 1-g shaking table tests. From the comparison, it was found that the calculated displacements from the suggested method showed good agreement with the measured displacements of the quay walls. It was also found that the excess pore pressure in backfill soils is a governing influence on the dynamic behavior of quay walls.

채취 시기가 다른 표고버섯의 첨가가 SHR 흰쥐의 혈압 및 혈청 지질 수준에 미치는 영향 (The Supplementary Effects of Harvesting Lentinus edodes at Different Times on Treating Blood Pressure and Serum Lipid Levels in Spontaneously Hypertensive Rats)

  • 이성현;박홍주;조용식;조수묵;김미자
    • 한국지역사회생활과학회지
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    • 제15권2호
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    • pp.65-71
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    • 2004
  • Many studies have shown that Letinus edodes has some effect on reducing blood pressure and lipid levels of animals with high pressure and hyperlipidemia. The cost of Letinus edodes varies depending on when it is harvested, and yet there has been no data collected on the bio-functional effects of Letinus edodes harvested at different times. This study was conducted to investigate the supplementary effects of Letinus edodes harvested at different times on blood pressure and blood lipid levels of hypertensive rats. Three kinds of experimental diets - control (CO), early harvested Lentinus deodes (EL), and late harvested Lentinus edodes (LL) - were supplied to spontaneously hypertensive rats (SHR) for eight weeks. The diet intake, body weight, organ weight, and serum lipid levels were subsequently measured. No significant difference was observed in diet intake and in the respective weights of the body, liver, and epididymal fat pad among experimental groups. The levels of systolic and disastolic blood pressure were significantly lower in the LE and LL groups than those in the CO group; and the concentration of serum total cholesterol was also lower in the LE and LL groups than in the CO group. These results confirm that Lentinus edodes reduces blood pressure levels and serum total cholesterol concentration in spontaneously hypertensive rats. But the effects of Lentinus edodes did not differ significantly based on whether the Lentinus edodes was harvested early or late.

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침구 치료와 가미십전탕을 병행하여 호전된 4도 욕창 환자 치험 1례 (A Case Report of Stage 4 Pressure Ulcer Patient Treated with Acupuncture and the Herbal Medicine Gamisipjeon-tang)

  • 류혜랑;강은진;김영균;김경민
    • 대한한방내과학회지
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    • 제38권5호
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    • pp.619-627
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    • 2017
  • Objectives: The purpose of this case study is to report the effect of oriental medicine on pressure ulcers. Methods: We treated a patient with a pressure ulcer with acupuncture, Jaungo, and Gamisipjeon-tang. We started with herbal medicine only, and then added the acupuncture treatment after one month. We treated the sore for a total of 4 months. We measured the size and depth of the ulcer and graded it with a National Pressure Ulcer Advisory Panel (NPUAP) score once every two weeks. Results & Conclusions: Even though the wound was not cured completely, the total size of the pressure ulcer was reduced and the NPUAP stage was improved from 4 to 3. Therefore, Korean medicine could be an effective treatment for improving pressure ulcers.

요가 프로그램이 본태성 고혈압 노인환자의 혈압하강에 미치는 효과 (The Effect of Yoga Program on Reduced Blood Pressure in Elderly′s Essential Hypertension)

  • 박형숙;김윤진;김영희
    • 대한간호학회지
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    • 제32권5호
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    • pp.633-642
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    • 2002
  • The purpose of this study was to evaluate the effect of a Yoga program on decreasing blood pressure in elderly patients with essential hypertension and to suggest a yoga program effective as a nursing intervention tool to reduced blood pressure with increasing life satisfaction. Method: The subjects of this study were 24 elderly's essential hypertension, who practiced yoga by three times a week for 8 weeks. In order to evaluate the effect of the yoga program, blood pressure, physiological parameters (Total cholesterol, HDL, LDL, triglycerides) and level of life satisfaction were measured before and after the training. Collected date were analyzed by SPSSWIN program. Result: 1) There were significant reduction in systolic and diastolic blood pressure. 2) There were significant reductions in total cholesterol, LDL, triglycerides but no significant increased in HDL. 3) Blood pressure changes were time specific : Both of systolic and diastolic blood pressures were significantly reduced after 2weeks. 4) There was a significant increase in life satisfaction. Conclusion: The results proved that a yoga program was an effective nursing intervention to reduce blood pressure and to increased life satisfaction for elderly patients with essential hypertension.

20대 여성을 위한 의복압 경감 브래지어 설계 (The Plan on Brassiere of Reduce Clothing Pressure for the Twenties Aged Women)

  • 박유신
    • 한국패션뷰티학회지
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    • 제4권3호
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    • pp.40-44
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    • 2006
  • This study is on the brassiere of reduce clothing pressure. To set the measurements of bras for women in their 20s, considering the comfortableness in wearing and tightness, this paper conducted a questionnaire survey concerning breasts and bras as well as measurements of body and contact surface pressure. As a result of comparing the discrepancies between the lower chest circumferences of the body and the bra, it was revealed that 67.0% were wearing one that was bigger than the body size. Most of them mentioned 'feeling of tightness' as a reason(60.4%), which suggests there are problems of the total length and elasticity in the process of making bras. The favorite bra types are wire type(57.9%), mold type(24.3%), and strapless type(10.4%).it is recommended that the total length of lower chest circumference be increased. The result and the recommendations of this study are as follows: First, the total length of brassiere be increased by 5cm from the current patterns in the process of manufacturing. Second, elasticity of the lower-side tapes be extended from 120% to 170%.

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수치계산에 의한 축류터보기계의 유동장과 유동온실의 평가 III [회전차 익말단의 누설손실과 효율저하에 대한 평가] (Evaluation of Flowfield and Flow Losses insied Axial Turbomachinery Using Numerical Calculation [Evaluation of Tip Leakage Loss and Reduction of Efficiency by Tip Clearance])

  • 노수혁;조강래
    • 유체기계공업학회:학술대회논문집
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    • 유체기계공업학회 1998년도 유체기계 연구개발 발표회 논문집
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    • pp.240-247
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    • 1998
  • Leakage vortices formed near blade tip causes an increase of total pressure loss near casing endwall region and as a result, the efficiency of rotor decreases. The reduction of rotor efficiency is related to the size of tip clearance. In this study, the three-dimensional flowfields in an axial flow rotor were calculated with varying tip clearance under various flow rates, and the numerical results were compared with experimental ones. The effects of tip clearance and attack angle on the leakage vortex and overall performance, and the less distributions were investigated through numerical calculations. In this study, tip leakage flow rate and total pressure loss by tip clearance were evaluated using numerical results and aprroximate equations were presented to evaluate the reduction of rotor efficiency by tip leakage flow.

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