• 유공압시스템학회:학술대회논문집
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• 유공압시스템학회 2010년도 춘계학술대회
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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.

• 한국분무공학회지
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• 제10권4호
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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.

• 한국유체기계학회 논문집
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• 제12권2호
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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.

• 성인간호학회지
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• 제23권2호
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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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• 유체기계공업학회 2005년도 연구개발 발표회 논문집
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• pp.542-545
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• 2005

• 한국콘텐츠학회논문지
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• 제17권7호
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• pp.265-275
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• 2017

본 연구는 장례식장에서 사망자를 위생적으로 관리하기 위해 사망의 장소, 종류 및 원인 등 사망자들의 유형에 따라 체액 분출 등 사후 어떤 변화가 있는지 알아보고자 하였다. 사망자 858명을 대상으로 조사한 결과 평균 연령은 68.6세이며, 주요 사망의 원인은 83.0%가 병사이며, 사망 장소는 79.5%가 의료기관에서 발생되었다. 사망자에서 발생되는 체액 분출율은 전체 사망자의 46.2%에서 조사되었고, 사망의 종류에 따라서는 사고사가 78.8%로 가장 높고, 노화사는 10.8%로 가장 낮았다. 사망의 장소에 따른 의료기관 사망자는 46.3%, 주택 사망자는 38.6%인데 반해 기타 장소는 77.4%로 높았다. 사망의 원인으로 직접, 중간 및 선행 사인이 기록된 사망자 수는 크게 다르지만 체액 분출 비율은 비슷하였다. 장기 및 계통별 사망자 수는 직접, 중간 및 선행 사인 모두 호흡기질환과 심장질환 사망자 수가 가장 많고, 체액 분출은 직접 사인은 간질환 사망자가 가장 높고 소화기 및 혈액순환계 순이며, 중간 및 선행 사인에서는 기타 및 사고사가 가장 높은 비율을 보였다. 사망의 원인에 기록된 질병을 기준으로 한 사망자 수는 직접 사인은 심폐부전이 96명으로 가장 많고 폐렴 및 패혈증 순이며, 체액 분출은 사망자 수가 15명 이상 기준으로 담관암(73.3%)이 가장 높고, 췌장암, 중증뇌손상 및 간암 순으로 많았다. 따라서 사망자의 위생적 관리를 위해서는 보다 정확한 질병명과 발병기간을 명시하도록 하여야 하고, 사망자 이송과정에서는 관련 정보가 문서화 되고 체계적인 전달 시스템이 될 수 있도록 제도화 하여야 할 것이다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회B
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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.

• 한국소음진동공학회논문집
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• 제11권8호
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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.

• 한국연소학회:학술대회논문집
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• 한국연소학회 제26회 KOSCO SYMPOSIUM 논문집
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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.

• Journal of Mechanical Science and Technology
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• 제15권8호
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• pp.1188-1195
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• 2001

A numerical analysis has been carried out to investigate the influences of thermosolutal convection on the heat and mass transfer and solute segregation in crystals grown by the vertical Bridgman technique. The governing equations are solved by a finite-volume method using the power law scheme and the SIMPLE algorithm in which body-fitted coordinate system has been used. A primary convective cell driven by thermal gradients forms in the bulk of the domain, while a secondary convective cell driven by solutal gradients forms near interface. As the solutal Rayleigh number increases, secondary cell becomes to be stronger and has a great influence on the radial concentration along the interface.