• Journal of Electrical Engineering and Technology
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• 제12권2호
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• pp.852-857
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• 2017

In this paper, measurements of ion mobility were performed in oxygen at gas pressures of 44.52 - 101.19 kPa using the drift tube method. Over this pressure range, mobility values were within the limits of 1.796 to $3.821cm^2{\cdot}V^{-1}{\cdot}s^{-1}$ were determined and ion mobility shown to decrease non-linearly with increasing gas pressure towards a certain level of saturation. Ion mobility measured in air was lower than that measured in oxygen at the same gas pressure. Finally, a parameter correction method for calibrating the relationship between the ion mobility and gas pressure in oxygen was proposed.

• 한국공간구조학회논문집
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• 제2권1호
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• pp.67-73
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• 2002

Measurement of fluctuating pressure by tube system is carefully designed due to the organ-pipe resonance. It is necessary to correct the pressure before analysis. The three method for correction the distortion fluctuation pressure short tube length and the frequency response functions and insert a restrictor in the tube to increase the damping. The first method is useful when the tube length is short. In second method, the distorted signal through the tubing transformed into the frequency domain, dividing by transfer function and inverse fourier transforming back into the time domain gives the required pressure signal. In this paper three types of tubing which have different length of 100cm, 150cm, 200cm were experimented the distorted signal and correct the distortion signal

• 대한기계학회:학술대회논문집
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• 대한기계학회 2002년도 학술대회지
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• pp.553-556
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• 2002

A numerical study on the use of the momentum interpolation mettled for flows with a large body force is presented. The inherent problems of the momentum interpolation method are discussed first. Numerical experiments are performed for a typical flow involving a large body force. The tact that the momentum interpolation method may result in physically unrealistic solutions is demonstrated. Numerical experiments changing the numerical grid have shown that a simple way of removing the physically unrealistic solution is a proper grid refinement where there is a large pressure gradient. An effective way of specifying the pressure and pressure correction at the boundary by a local mass conservation near the boundary is proposed, and it is shown that this method can effectively remove the inherent problem of the specification of pressure and pressure correction at the boundary when one uses the momentum interpolation method.

• 한국압력기기공학회 논문집
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• 제14권2호
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• pp.69-76
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• 2018

The paper presents preliminary investigation results for the effect of the baseline correction in the acceleration excitation method on finite element seismic analysis results (such as accumulated equivalent plastic strain, equivalent plastic strain considering cyclic plasticity, von Mises effective stress, etc) of nuclear safety Class I components. For investigation, finite element elastic-plastic time-history seismic analysis is performed for a surge line including a pressurizer lower head, a pressurizer surge nozzle, a surge piping, and a hot leg surge nozzle using the Chaboche hardening model. Analysis is performed for various seismic loading methods such as acceleration excitation methods with and without the baseline correction, and a displacement excitation method. Comparing finite element analysis results, the effect of the baseline correction is investigated. As a result of the investigation, it is identified that finite element analysis results using the three methods do not show significant difference.

• 한국산학기술학회논문지
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• 제16권3호
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• pp.2064-2072
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• 2015

본 연구는 탄성밴드운동과 스트레칭을 이용한 내반슬 교정운동프로그램이 내반슬 대학생의 무릎간 간격, Q-각, 족압에 미치는 영향에 대해 알아보는데 그 목적이 있다. 총 30명의 내반슬 대학생을 대상으로 실험군과 대조군을 각각 15명씩 무작위 선정하여 실험군은 6주 동안 스트레칭과 탄성밴드를 이용한 교정 운동 프로그램을 실시하였고, 대조군은 일상생활을 유지하게 하였다. 중재 전 후 무릎사이 간격과 Q-각의 변화를 알아보기 위해서 computed radiography X-ray를, 족압 분포변화를 확인하기 위해 RSscan을 사용하여 족압 분포를 측정하였다. 6주간의 교정운동프로그램 실시한 결과, 중재 전보다 중재 후 무릎간 간격이 유의하게 감소하였고, Q-각은 유의하게 증가하였다. 족압 분포는 중재 후에 2-5 지골과 1, 2, 3 중족골 족압이 증가하였으며, 4, 5 중족골 족압은 유의하게 감소하였다 (p<.05). 이러한 결과를 바탕으로 본 연구에서 실시한 내반슬 교정운동프로그램이 신체의 정렬과 족압 분포도의 배열을 맞추는데 효과가 있으며, 이를 통해 내반슬 변형자에게 긍정적인 효과가 있음을 확인하였다.

• 한국컴퓨터정보학회논문지
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• 제27권8호
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• pp.161-168
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• 2022

본 연구에서는 20대 경도비만 남성을 대상으로 시판 남성용 상체 보정속옷에 대한 착용만족도를 알아보고 개선점을 파악하고자 하였다. 피험자는 20대 남성이면서 BMI지수가 25~30인 (경도비만)인 사람으로 15명을 선정했다. 연구 결과, 남성들의 보정속옷에 대한 인지도와 관심도는 낮은 편이었다. 착용 만족도 조사에서는 입고 벗을 때 불편하다고 부정적으로 답한 사람이 많았다. 압박감면에서는 초반에는 압박감이 강하다고 느끼지만 시간이 지날수록 익숙진다고 하였다. 답답함과 더위와 관련하여 부정적으로 응답한 사람이 과반을 넘었고 땀 흡수 및 배출과 관련해서도 부정적인 의견이 많았다. 시각적인 부문에서는 가슴 보정, 허리 옆부분 보정, 허리 앞부분에서 모두 긍정적인 반응을 보였다. 결론적으로, 남성용 상체 보정속옷의 개선점은 과한 압박감이 가져다주는 답답함과 소화불량, 여름철을 고려하여 더위와 땀과 관련한 기능성 부분인 것으로 나타났다.

• 한국정밀공학회지
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• 제22권4호
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• pp.159-166
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• 2005

This study deals with the correction of gear tooth profile error by finish roll forming. First, we experimentally confirmed that the tooth profile error is a synthesis of the concave error and the pressure angle error. Since various types of tooth profile errors appear in the experiments, we introduced evaluation parameters for rolling gears to objectively evaluate profile quality. Using these evaluation parameters, we clarified the relationship among the tooth profile error, the addendum modification factor (A. M. factor), and the tool loading force. We verified the character of concave error, pressure angle error, tool loading force and number of cycles of finish roll forming by using a forced displacement method. This study makes clear that tool loading force and number of cycles of finish roll forming are very important factors that affect involute tooth profile error. The results of the experiment and analysis show that the proposed method reduces concave and pressure angle errors.

• Journal of Chest Surgery
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• 제28권11호
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• pp.1045-1048
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• 1995

Pulmonary atresia with VSD is uncommon congenital anomaly with high mortality in neonatal period.Recently we experienced surgical correction of pulmonary atresia with VSD. The case was 2 month old male patient diagnosed as pulmonary atresia with VSD and PDA. Atretic pulmonary artery segment from Rt ventricular infundibulum to pulmonary artery was lcm in length. The pulmonary trunk tapered toward Right ventricular infundibulum and resulted in blind pouch with diameter of lmm. The left pulmonary artery was stenosed at just proximal and distal part to which PDA was connected. Total correction was undertaken which consisted of PDA ligation, dacron patch closure of VSD, establishment of continuity between right ventricle and pulmonary artery with autogenous pericardium. Postoperative systolic fight ventricular pressure and left ventricular pressure ratio was 0.7. In patient with pulmonary atresia with VSD it is advisable to perform a corrective operation, whenever the size and anatomy of pulmonary artery are acceptable for it.

• 한국자동차공학회논문집
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• 제13권1호
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• pp.28-35
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• 2005

Fuel injection rate of an injector is affected by various injection conditions such as injection duration, fuel temperature, injection pressure, and voltage in LPG liquid injection systems for either a port-fuel-injection(PFI) or a direct injection(DI) in a cylinder. Even fuel injection conditions are changed, the air-fuel ratio should be accurately controlled to educe exhaust emissions. In this study, correction factor for the fuel injection rate of an injector is derived from the density ratio and the pressure difference ratio. A voltage correction factor is researched from injection test results on an LPG liquid injection engine. A compensation method of the fuel injection rate is proposed for a fuel injection control system. The experimental results for the LPG liquid injection system in a SI-engine show that this system works well on experimental range of engine speed and load conditions. And the fuel injection rate is accurately controlled by the proposed compensation method.

• 대한기계학회논문집B
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• 제21권3호
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• pp.341-349
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• 1997

The characteristics of defect correction method are discussed in a sample heat conduction problem showing the numerical solution of the error correction equation can predict the error of the numerical solution of the original governing equation. A way of using defect correction method combined with the existing algorithm for the incompressible fluid flow, is proposed and subsequently tested for the driven square cavity problem. The error correction equations for the continuity equation and the momentum equations are considered to estimate the errors of the numerical solutions of the original governing equations. With this new approach, better velocity and pressure fields can be obtained by correcting the original numerical solutions using the estimated errors. These calculated errors also can be used to estimate the orders of magnitude of the errors of the original numerical solutions.