• 유공압시스템학회:학술대회논문집
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• 2010.06a
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• pp.116-125
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• 2010

In this study, a novel hydraulic energy-regenerative system was presented from its proposal through its modeling to its control. The system was based on a closed-loop hydrostatic transmission and used a hydraulic accumulator as the energy storage system in a novel configuration to recover the kinetic energy without any reversion of the fluid flow. The displacement variation in the secondary unit was reduced, which widened the uses of several types of hydraulic pump/motors for the secondary unit. The proposed system was modeled based on its physical attributes. Simulation and experiments were performed to evaluate the validity of the employed mathematical model and the energy recovery potential of the system. The experimental results indicated that the round trip recovery efficiency varied from 22% to 59% for the test bench.

• Journal of ILASS-Korea
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• v.10 no.4
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• pp.26-31
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• 2005

Today, the research to examine a fact that interaction between the air and the fluid free surface affects the steady state flow and air. We proved the interaction between vortex pairs and free surface on each condition that is created by the end of delta wings. Another purpose of this study is to investigate the effect of surface active material which call change the surface tension and we must consider when we refer to turbulent flow on surface tension. Therefore, this research examined the growth process of vortex pairs on condition of clean, contaminated free surface and wall after we made vortex pairs through counter rotating flaps. The results of this study suggest that vortex pairs in clean free surface rise safely but the vortex pairs in contaminated free surface and rigid, no slip is made secondary vortex or rebounding. However the secondary vortex in rigid, no slip is stronger than before. and we can find the vortex shape which roll up more completely. However, these will disappear by the effect of wall.

• The KSFM Journal of Fluid Machinery
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• v.12 no.2
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• pp.8-16
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• 2009

The objective of this study is to investigate the three-dimensional turbulence flow characteristics of a rotor passage of an one-stage axial flow gas turbine and to investigate the effects of a boundary layer fence installed on the hub endwall of the rotor passage. Secondary flows occurring within the rotor passage (e.g. horseshoe vortex, passage vortex, and cross flow) cause secondary loss and reduce turbine efficiency. To control these secondary flows, a boundary layer fence measuring half the height of the thickness of the inlet boundary layer was installed on the hub endwall of the rotor passage. This study was performed numerically. The results show that the wake and secondary flows generated by the stator reduced the rotor load to constrain the development of cross flow and secondary flow reinforced by the rotor passage. In addition, the secondary vortices occurring within the rotor passage were reduced by the rotation of the rotor. Although, the boundary layer fence induced additional vortices, giving rise to an additional loss of turbine, its presence was shown to reduce the total pressure loss when compared to effects of the case without fence regardless of the relative position of blades by enervating secondary vortices occurred within the rotor passage.

• Korean Journal of Adult Nursing
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• v.23 no.2
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• pp.180-188
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• 2011

Purpose: This study was to identify nursing diagnosis-outcome-intervention (NANDA- NOC-NIC: NNN) linkages applied to inpatients in general surgical nursing units. Methods: We developed the NNN linkage computerized nursing process program, which consisted of the 107 nursing outcomes and the 190 nursing interventions linked to the 39 nursing diagnoses. This program was applied to 324 patients who admitted to those nursing units from July, 2004 to February, 2005. Results: First, nursing outcomes of each nursing diagnosis were identified as follows: for 'acute pain', pain control, pain level, and comfort level; for 'risk for infection', wound healing: primary intention, wound healing: secondary intention, and infection status; for 'nausea', nutritional status: food & fluid intake, comfort level, symptom severity and hydration. Second, major nursing interventions for each nursing outcome were analyzed as follows: for pain control or comfort level, pain management and medication management; for pain level, pain management and analgesic administration; for wound healing: primary intention, incision site care and wound care; for Wound healing: secondary intention or infection status, infection control; for nutritional status: food & fluid intake, fluid monitoring; for comfort level, nausea management; for symptom severity, nausea management and vomiting management; for hydration, fluid/electrolyte management. Conclusion: This identified NNN linkages will facilitate the use of nursing process in surgical nursing practice and documentation systems.

• 유체기계공업학회:학술대회논문집
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• 2005.12a
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• pp.542-545
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• 2005

• The Journal of the Korea Contents Association
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• v.17 no.7
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• pp.265-275
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• 2017

The aim of this study was to examine fluid excretions and changes in deceased bodies depending on type, location of, and causes of death for hygienic management of funeral homes. Based on the 858 cadavers studied, the average age at the time of death is 68.6 years, 83.0% had illness as the cause of death, and 79.5% passed away in a medical facility. Fluid excretion was observed in 46.2% of the cadavers. In manner of death, 78.8% of deaths -highest percentage- was due to an accident and 10.8% of deaths - lowest percentage- was due to age. Fluid excretion was observed in 46.3% of cadavers from medical facilities, 38.6% of cadavers from homes and 77.4% of cadavers from miscellaneous locations. There were various number of cadavers with recorded immediate, secondary and underlying cause of death; however, the fluid excretion rate was similar. In analyzing the immediate, secondary and underlying cause of death, respiratory and heart disease were the most common causes of death in categories of body organ and system. In terms of fluid excretion, liver disease followed by digestive and circulatory diseases were most common in immediate cause of death. Accidents and miscellaneous circumstances were most common amongst secondary and underlying causes of death for cadavers with fluid excretion. Based on the recorded illnesses of the cadavers, cardiopulmonary failure was most common as evident in 96 cadavers followed by pneumonia and sepsis. Cholangiocarcinoma (73.3%) had the highest rate of fluid excretion followed by pancreatic cancer, severe brain injury and liver cancer amongst categories of illnesses with more than 15 cadavers.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.2769-2774
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• 2007

In vacuum ejector-diffuser systems where a finite volume secondary chamber is used, the secondary jet exhibits transient characteristics during start-up. A steady state is achieved after some time in which mass entrainment prevails indefinitely inside the ejector, though there is no flow from the secondary chamber. An attempt is made in this work to study the infinite entrainment of secondary jet into the primary jet from a finite secondary chamber, with the help of a computational fluid dynamics method. The present study is also intended to identify the operating range of vacuum ejector-diffuser systems where the steady flow assumption can be applied without uncertainty. The results obtained show that the only condition in which an infinite mass entrainment is possible is the generation of a re-circulation zone near the primary nozzle exit. The flow in the secondary chamber attains a state of dynamic equilibrium at this point. Steady flow assumption is valid only after this point.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.11 no.8
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• pp.314-321
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• 2001

Static and oscillatory loss of stability of composite pipes conveying fluid is Investigated. The theory of than walled beams is applied and transverse shear. rotary inertia, primary and secondary warping effects are incorporated. The governing equations and the associated boundary conditions are derived through Hamilton's variational principle. The governing equations and the associated boundary conditions are transformed to an eigenvlaue problem which provides the Information about the dynamic characteristics of the system. Numerical analysis is performed by using extended Gelerkin method. Variation of critical velocity of fluid with fiber angles and mass patios of fluid to pipe Including fluid is investigated.

• 유체기계공업학회:학술대회논문집
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• 2001.11a
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• pp.197-202
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• 2001

The heat produced by the fission in the fuel of HANARO, 30 MW of research reactor, was transferred from the primary cooling water to the secondary cooling water through heat exchangers. The secondary cooling water absorbed the heat was circulated by secondary cooling pumps and cooled through 33 MW of cooling tower. Each capacity of the three secondary cooling pumps was fifty percent ($50\%$) of full load. The two pumps were normally operated and the other pump was standby. One of the secondary cooling pumps has often get troubles by high vibration. To release these troubles the pump shaft has been re-aligned, the pump bearing has been replaced with new one, the shaft sleeve has been replaced with new one, the shaft and the impeller have been re-weight balanced representatively or the vibration of motor has been tested by disconnecting the shaft of pump. But the high vibration of pump cannot be cleared. We find out the weight balance trouble of the assembly that the impeller is installed in the shaft. After clearing the trouble, the high vibration is released and the pump is operated with smooth. In this paper the trouble solution of secondary cooling pump is described including the reason of high vibration.

• 한국연소학회:학술대회논문집
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• 2003.05a
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• pp.111-117
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• 2003

The present study discusses about the combustion and thermal flow characteristics of a G+R type incinerator, which is under construction for MAPO Incineration system, to evaluate the effects of various operating and design parameters. A bed combustion model is developed to simulate the waste bed combustion on the stoker. The effects of waste composition and primary air distribution are estimated. The results of the waste bed combustion model is applied to CFD(computational fluid dynamics) simulation, which simulates the detail of the thermal flow in the combustion chamber. The effects of bypass damper opening ratio, primary air distribution, and secondary air jet configuration are discussed.