• 한국군사과학기술학회지
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• 제3권1호
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• pp.207-217
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• 2000

A fire fighting characteristic by a single evaporating droplet in the case of a fire of military enclosure space was studied experimentally. Transient cooling of solid surface by water droplet evaporation has been investigated through controlled experiments using a heated brass cylinder. Quantitative predictions of droplet evaporation time and in-depth transient temperature distribution in solid have been made. The particular interest was in the removal of thermal energy from the heated cylinder by evaporative cooling. A $10{\mu}1$ single droplet is deposited on a horizontal brass surface with initial temperatures in the range of $90^{\circ}C{\sim}130^{\circ}C.$ The results can be summarized as follows; Evaporating droplet was divided into three different configuration. Evaporation time was predicted as a function of initial surface temperature ($t_c=492.62-6.89T_{s0}+0.0248T_{s0}^2).$ The contact temperature was predicted as a function of initial surface temperature( $T_{i}$=0.94 $T_{s0}$+1.4), The parameter ${\beta}_o$ was predicted as a function of initial surface temperature( ${\beta}_0$ : 0.O0312 $T_{s0}+0.932$)>)>)

• 한국유체기계학회 논문집
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• 제14권6호
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• pp.18-25
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• 2011

A boundary-layer pump with a single disk has been experimented to obtain its characteristic curve by changing the impeller of a centrifugal pump to a single disk. The primary objective to use of these types of pumps is to avoid hurting water life during transportation unnecessarily. The change of impeller should degrade the performance of pump, so we used the method to increase the roughness on the disk with sandpaper and mesh. The enhancement of shear force from the rotation of disk to the internal flow brought an augmentation of momentum transport, and the characteristics were far improved from the original single-disk pump without decreasing the survival rate of water life in the case of Pseudobagrus fulvidraco (bullhead fish). However, in the case of Artemia cyst (zooplankton), the survival rate was very degraded due to the micro scale smaller than turbulent eddy size. The result of this study could be used for the design of transportation and bio-filtering of water lying on a specific bandwidth of its scale of size.

• 대한의생명과학회지
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• 제28권4호
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• pp.327-333
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• 2022

The DNA profiling of short tandem repeat (STR) markers is a powerful tool for forensic identification and forensic paternity testing. However, STR loci are susceptible to mutation that cause mismatches between parents and children when paternity is tested. Herein, we examined paternity disputes with 23 autosomal STR loci using two commercial human identification kits and revealed successive mismatches at the D13S317 locus across three generations of a Korean family. Additionally, we investigated 12 X-chromosomal STRs and discovered an inconsistency at the DXS10148 locus between the father and daughter of the same Korean family. Furthermore, we confirmed STR genotypes at the D13S317 and DXS10148 loci of the family using sequencing analysis. Consequently, we identified a successive single-step mutation at the D13S317 locus and one single-step mutation at the DXS10148 locus in three generations of the Korean family. Therefore, this case study may be useful for interpreting and understanding forensic paternity tests.

• 지식경영연구
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• 제3권1호
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• pp.93-106
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• 2002

Knowledge management is a recent area in business administration that deals with how to leverage knowledge as a key asset and resource in modern organizations. Also, Knowledge systems are the single most important industrial and commercial offspring of the discipline called artificial intelligence. A Case Based Reasoning(CBR) system solves new problems by recalling adapting previous solutions. This paper presents the results of a recent empirical study. Furthermore this study proposes a CBR Methodology designed to manage knowledge of Hana company under e-business.

• 전기학회논문지
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• 제62권5호
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• pp.604-611
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• 2013

This paper presents an second harmonic elimination method based on the impedance variation scheme. Through the power quality analysis from the nonlinear loads connected on the power system, the second harmonic problems have been analyzed with a case study analysis and the experiments. In the paper, the second Harmonic generation was simulated with a single phase SCR rectifier and the analytical model is proposed for the second harmonic generation. A novel impedance variation scheme is proposed and analyzed to eliminate the second harmonic. The experiment has been performed on the 60(MVA) industry manufacturing plant. The experimental result demonstrates the proposed impedance variation scheme successfully operate on the 60(MVA) industry manufacturing plant.

• 천문학회보
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• 제43권2호
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• pp.45.2-45.2
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• 2018

Twisted magnetic flux tubes (also called magnetic flux ropes) are believed to play a crucial role in solar eruptive phenomena. The evolution of a single flux rope with or without the influence of an overlying field of a simple geometry has been extensively studied and its physics is rather well understood. Observations show that interacting flux tubes are often involved in solar eruptions. It was Lau and Finn (1996) who intensively studied the interaction between two flux ropes, whose footpoints are anchored in two parallel planes. In this too simplified setting, the curvature of the flux rope axial fields is totally ignored. In our study, the footpoints of flux ropes are placed in a single plane containing a polarity inversion line as in the real solar active region. Our simulation study is performed for four cases: (1) co-axial field and co-axial current (co-helicity), (2) counter-axial field and co-axial current (counter-helicity), (3) co-axial field and counter-axial current (counter-helicity), and (4) counter-axial field and counter-axial current (co-helicity). Except case 3, each case is found to be related with certain eruptive features.

• 한국가시화정보학회지
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• 제18권3호
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• pp.52-60
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• 2020

When a bubble reaches a free surface, a bursting of the bubble produces a high speed jet. Despite its practical importance, significant effort has been devoted to investigate a bursting jet by a single bubble near a free surface. In the present study, we perform numerical simulations of bubbles in a tandem arrangement at Bo=0.05. The configuration of the tandem bubbles is systematically varied by changing a radius of a following bubble (RF) and the gap distance between two bubbles (L). Compared to a single bubble case, we show that the bursting bubble in the tandem arrangement accelerates, and the jet velocity increases. Moreover, we find that a critical gap distance at which the jet velocity unexpectedly changes exists in the tandem case.

• 인간행동과 음악연구
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• 제8권2호
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• pp.21-46
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• 2011

본 연구의 목적은 치료적 음악 만들기가 여성 한부모 가족의 의사소통에 어떠한 변화가 나타나는지 알아보고자 함에 있다. 이를 위해 본 연구에서는 이혼으로 인한 여성 한부모 2가족을 대상으로 노래 만들기, 즉흥 모방하기, 오스티나토 창작하기, 합주하기로 구성된 치료적 음악 만들기 프로그램을 14회기 동안 진행하였다. 본 연구의 결과는 다음과 같다. 첫째, 프로그램의 사전, 사후에 측정한 대상자들의 부모-자녀 간 의사소통 점수가 대상자 B는 59에서 69.5로 상승하였으나, 대상자 A는 잦은 결석 및 음악 적용의 차이로 인해 81에서 75.5로 감소하였다. 둘째, 대상자들의 언어적 비언어적, 음악적 반응을 분석한 결과 대상자 B는 의사소통 유형에 따른 모-녀의 역기능적 의사소통이 후기로 갈수록 감소하고, 기능적 의사소통이 증가하는 변화가 있었다. 대상자 A는 언어적 비언어적 의사소통에서 초기에는 역기능적 의사소통이 많이 나타나다가 8회기 이후 기능적 의사소통이 증가하였고, 음악적 의사소통에서는 언어적 비언어적 의사소통과 다르게 초기부터 기능적 의사소통을 주로 보였으며, 프로그램 후반까지 유지하였다.

• 한국환경과학회지
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• 제27권6호
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• pp.359-369
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• 2018

A model has been developed to predict natural ventilation in a single zone building with large openings. This study first presents pressure-based equations on natural ventilation, that include the combined effect of wind and thermal buoyancy. Moreover, the concept of neutral pressure level(NPL) is introduced to consider the two-way flow through a large opening. The total pressure differences across the opening and the NPL are calculated, and nonlinear equations are solved to find the zonal pressure to satisfy mass conservation. For this analysis, an iterative technique of successively approximating the zonal pressure is used. The results of applying this study model to several simple cases are as follows. When there is no wind and only the stack effect is caused, a one-way flow occurs in both the top and bottom openings in the case of two openings of equal-area, and a one-way flow occurs in the top opening; however, a two-way flow occurs in the bottom opening in the case of two openings of unequal-area. When there is a wind effect, regardless of whether the outside air temperature is lower or higher than the indoor air temperature, air flows into the room through the bottom opening and out of the room through the top opening. As the wind velocity increases, the wind effect appears to be more influential than the stack effect owing to the temperature difference.

• The Journal of Korean Physical Therapy
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• 제21권3호
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• pp.119-124
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• 2009

Purpose: The National Institute for Occupational Safety and Health (NIOSH) lifting equation (NLE) is a useful tool to ergonomically analyze a workload. The NLE has high reliability and it can assess tasks by analyzing the work process. The purpose of this case study was to try using the NLE to analyze the workload of transferring patients by physical therapists in the hospital setting. Methods: We observed a physical therapist (PT) transferring patients from a wheelchair to a tilt table and a therapeutic table in one day. Two types of patient transferring methods were evaluated; (1) the manual single person method of stand, pivot and transfer, and (2) manual two person lifting under the thigh and grasping the waist for totally dependent patients. Results: The NIOSH lifting indexes of a person grasping the waist during the manual two person lifting were 5.52~4.48 according to the patient's weight. The NIOSH lifting indexes were 3.34 and 4.48 for the tasks performed by the manual single person method. Conclusion: Because transferring patients is not done very frequently, patients transferring tasks by a PT are not included as one of the musculoskeletal disorder related risky work criteria of the Korea Ministry of Labor. But the NIOSH lifting indexes of a person grasping the waist during the manual two person lifting and the manual single person method were over the NIOSH recommended weight limit threshold.