• Structural Engineering and Mechanics
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• 제3권6호
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• pp.583-592
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• 1995

The concept of "Saturation Impulse" for rigid, perfectly plastic structures with finite-deflections subjected to dynamic loading was put forward by Zhao, Yu and Fang (1994a). This paper extends the concept of Saturation Impulse to the analysis of structures such as simply supported circular plates, simply supported and fully clamped square plates, and cylindrical shells subjected to rectangular pressure pulses in the medium load range. Both upper and lower bounds of nondimensional saturation impulses are presented.

• 여성건강간호학회지
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• 제15권1호
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• pp.32-42
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• 2009

Purpose: This study was done to examine the effects of abdominal breathing on VAS-Anxiety (VAS-A), blood pressure, peripheral skin temperature and saturation oxygen in pregnant women in preterm labor. Method: The study design was a matched control group interrupted time series. Forty-six women matched to gestational age were assigned to either the experimental group (26) or control group (20). Data were collected between March 2007 and May 2008. For the experimental treatment the women performed abdominal breathing 30 times, which took 5 minutes, and did one set of 5-minute abdominal breathing daily for three days. Data collection was done before and after the abdominal breathing to measure VAS-A, blood pressure, peripheral skin temperature and oxygen saturation. Descriptive, $X^2$, Mann-Whitney U tests were used to analyze the data with the SPSS/PC+Win 15.0 program. Result: For the experimental group there were significant decreases in VAS-A (Z=-4.37, p=.00), systolic blood pressure (Z=-3.38, p=.00), and an increase in skin temperature (Z=-4.50, p=.00) and oxygen saturation (Z=-3.66, p=.00). Conclusion: These findings suggest that abdominal breathing in pregnant women in preterm labor results in decreases in anxiety(VAS-A) including biological evidences such as systolic blood pressure, and increases in peripheral skin temperature and oxygen saturation. Further longitudinal study is needed on the lasting effects and obstetric and neonatal outcomes following abdominal breathing.

• 한국정밀공학회지
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• 제22권12호
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• pp.87-92
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• 2005

In microcellular injection molding, gas supply system is needed. But, that device is very expensive to attach to the injection molding machines. So, new method is needed and gas-pellets MCPs is one of the solutions. In gas-pellets MCPs, there will be strange characteristics. In this paper, some characteristics are described on the view point of saturation pressure and saturation time.

• 동력기계공학회지
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• 제11권1호
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• pp.63-69
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• 2007

The evaporation pressure drop of $CO_2$ (R-744) in a horizontal tube was investigated experimentally. The main components of the refrigerant loop are a receiver, a variable-speed pump, a mass flow meter, a pre-heater and an evaporator (test section). The test section consists of a smooth, horizontal stainless steel tube of 4.57 mm inner diameter. The experiments were conducted at saturation temperature of $-5^{\circ}C\;to\;5^{\circ}C$, and heat flux of 10 to $40kW/m^2$. The test results showed that the evaporation pressure drop of $CO_2$ are highly dependent on the vapor quality, heat flux and saturation temperature. The measured pressure drop during the evaporation process of $CO_2$ increases with increased mass flux, and decreased saturation temperature. The evaporation pressure drop of $CO_2$ is much lower than that of R 22. In comparison with test results and existing correlations, the best fit of the present experimental data is obtained with the previous correlation. But existing correlations failed to predict the evaporation pressure drop of $CO_2$. Therefore, it is necessary to develop reliable and accurate predictions determining the evaporation pressure drop of $CO_2$ in a horizontal tube.

• 한국광학회지
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• 제5권4호
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• pp.457-460
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• 1994

XeCl 레이저 증폭기의 포화 에너지 밀도와 소신호 이득계수를 활성기체의 압력을 변화시키면서 측정하였다. Xe이 30mb, He이 2000mb일 때, HCl이 34, 52, 73, 92으로 압력이 높아짐에 따라 포화 에너지 밀도는 1.3, 1.45, 2.0, $2.3mJ/\textrm{cm}^2$로 거의 선형적으로 증가하였지만 소신호 이득계수는 6.5, 7.5, 7.0, 7.0%/cm로 거의 변화하지 않았다.

• 지구물리와물리탐사
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• 제15권2호
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• pp.102-115
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• 2012

이 논문은 퇴적물내 포함되어 있는 가스하이드레이트의 포화도를 계산하는 여러 방법에 대하여 토론하고자 한다. 가스하이드레이트의 포화도를 계산하는 방법은 물리검층 자료를 이용하는 방법과 코어자료(압력코어 포함)를 이용하는 방법, 그리고 탄성파 탐사자료로부터 얻을 수 있는 속도 자료를 이용하는 방법 등 크게 세가지 방법으로 나눌 수 있다. 물리검층 자료중 전기비저항 자료를 이용하는 방법의 경우 Archie 식을 주로 이용하는데 이 경우 각각의 변수 값을 정확하게 정의하는 게 중요하다. 또한 가스하이드레이트의 산출형태도 포화도 계산에 큰 영향을 주기 때문에 주의해야 한다. 코어자료를 이용하는 경우 공극수의 염소량을 측정하는 방법과 압력코어를 취득할 경우 이를 이용하는 방법이 있다. 지금까지 발표된 정량적이고 가장 정확한 가스하이드레이트 포화도값을 구할 수 있는 방법이 압력코어를 이용하는 것이다. 그러나 이는 비용과 시간이 많이 소요되기 때문에 연속적인 자료를 얻기가 어렵다는 단점이 있다. 지금까지 발표된 가스하이드레이트 포화도 값을 비교해 보면 전기비저항 값을 이용한 경우가 가장 높은 값을 압력코어를 이용하여 측정한 경우가 가장 낮은 값을 보여주는 경향이 있다. 그러나 이러한 값이 모든 경우에 있어서 절대적인 경향을 보여준다고 볼 수는 없다. 그러므로 가스하이드레이트의 포화도를 정확하게 계산하기 위해서는 여러 가지 방법을 이용하여 계산해야 하며 이를 비교하여 가장 적절한 값을 사용해야 할 것이다.

• 한국철도학회논문집
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• 제8권1호
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• pp.57-62
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• 2005

The frost heaving pressure can be a problem for weakening of the railway roadbed material. This study was initiated to investigate the soils frost heaving pressure and physical characteristics(Liquid limit, permeability, SEM analysis) resulting from freezing and freezing-thawing cycle process. Therefore, upon freezing a saturated soil in a closed-system from the top, a considerable pressure was developed. Weathered granite soils, sandy soil were used in the laboratory freezing test which sometimes subjected to thermal gradients under closed-systems. The frost heaving pressure arising within the soil samples and the temperature of the samples inside were monitored with elapsed time. The degree of saturation versus heaving pressure curve is also presented for weathered granite soil and the maximum pressure is closely related to this curve. Based on the laboratory test results, fine-grained soils with strong attractive forces between soil grains md water molecules, and additional water is attracted into the pores leading to further volume changes and ice segregation.

• 성인간호학회지
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• 제21권2호
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• pp.141-154
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• 2009

Purpose: The purpose of this study was to compare the difference of change in oxygen saturation, vital signs and suction time taken for the suctioning during endotracheal suctioning performed with closed suction system and with opened suction system. Methods: Data were collected from 31 adult patients with ventilator treatment who were admitted to a university hospital in Seoul and the collection period was from July 1 to November 15, 2005. Oxygen saturation, heart rate, respiration rate and mean arterial pressure were collected immediately prior to the suctioning intervention, during and 1 and 5 minutes after the suctioning from opened suction system and closed suction system. Results: 1) The difference in oxygen saturation was statistically significant in recovery time for oxygen saturation to return to baseline values after suctioning was significantly rapid on closed suction system (p<.05). 2) The difference in heart rate, respiration rate and mean arterial pressure was statistically insignificant 3) The suction time was shorter in closed suction system. Conclusion: Closed suction system is more efficient, as compared with the open suction system in the ventilator treatment.

• 대한기계학회논문집
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• 제19권8호
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• pp.1999-2011
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• 1995

Computer simulation was conducted to study performance characteristics of air-cooled condenser of a double effect absorption heat pump with variations of saturation pressures and mass flow rates of the refrigerant ; volume flow rates, relative humidities and temperatures of the air The vertically installed condenser had the staggered tube array with continuous plate fins of wavy type. When the saturation pressure of the condenser was decreased from 760 torr to 20 torr, heat transfer rates and condensing rates of refrigerant were decreased. If excess refrigerant flows in the condenser, the pressure and saturation temperature of the condenser were increased which makes the refrigerating capacity of an absorption heat pump reduced.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2002년도 봄 학술발표회 논문집
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• pp.329-336
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• 2002

The earth structures and in-ground LNG tank, and buildings can be constructed with using artificial freezing method on the reclaimed land. In this study, upon freezing a saturated soil in a closed-system from the top, a considerable pressure was developed. The pressure is the result of the surface energy of a curved ice-water interface. The most significant of these parameters will have the greatest effect on the classification. In order to establish frost-susceptibility criteria based on frost heaving expansion pressure, more soils have to be tested. This study was initiated to investigate the soils frost heaving expansion pressure and moisture characteristics resulting from freezing and freezing-thawing cycle process. Weathered granite soils, sandy soil, sandy soil were used in the laboratory freezing test subjected to thermal gradients under closed- systems.