• 제목/요약/키워드: 이춘상

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CFD를 이용한 흡수탑 내 유동 균일효과 연구

  • 이춘만;이호경
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2004년도 춘계학술대회 논문요약집
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    • pp.106-106
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    • 2004
  • 보일러에서 연소된 후 배출된 가스는 탈황목적으로 설치된 흡수탑 내에 유입되어 Slurry Spray Nozzle에서 분사된 Limestone Slurry에 의해 배기가스중의 SO$_2$를 흡수한 다음 반응조로 떨어지게 되지만 분사된 액적의 일부는 배기가스의 압력에 의하여 같은 유동 방향으로 미세한 Mist의 형태로 배기가스와 함께 흡수탑의 Outlet Duct를 통해 빠져나간다. 이 Mist(액적크기 40 $\mu\textrm{m}$이하)에는 고형 성분이 함유되어 있는데 보통 Chloride농도가 높아 탈황설비 후단 (duct, GGH, Stack)에 plugging, 부식 등의 문제를 유발하므로 Spray Header상부에서 Mist Eliminator를 설치하여 Mist를 제거하도록 한다.(중략)

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전조 볼 나사 BCD 측정기 개발에 관한 연구

  • 이춘만;임상헌;김현철
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2004년도 춘계학술대회 논문요약집
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    • pp.184-184
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    • 2004
  • 볼 나사는 반도체ㆍLCDㆍPDP 등 전자제품 조립장비 제조업체와 CNC 공작기계, 정밀측정기계, 직교좌표로봇, 반송장치, 항공기용 유압구동장치 대체품, 전동공구, 파워 steering, 테이블 개폐장치 등에서 구동 장치 및 물품의 이송을 위해 대부분 사용되는 중요한 기계요소 중의 하나이다. 그것은 회전운동을 직선운동으로 전환해주는 기구부에 들어가는 가장 중요한 부품이며, 원통형의 봉에 나선형의 그루브를 가공한 장축의 나사와 단축의 너트 사이에 볼을 게재시켜 축의 회전 시 적은 구름마찰로 인해, 너트부가 직선 운동하는데 원활 하게 만들어진 기계요소이다.(중략)

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평금형 CNC 가공 S/W 개발에 관한 연구 (A Study on the Manufacture of Extrusion Square Die)

  • 박태원;조승래;이춘만
    • 소성∙가공
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    • 제9권2호
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    • pp.179-185
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    • 2000
  • Square dies are widely used for hot extrusion processes with high production rate, however, the design and manufacture of square dies mainly relies on experience of industrial engineers. To overcome such difficulty, this study presents a method of automatic generation of NC-codes for the manufacture of extrusion square dies. The result shows that the method can reduce the lead-time for the design and manufacture of square dies.

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Involute Curve의 Biarc Curve Fitting에 관한 연구 (A study on the biarc curve fitting of involute curve)

  • 이춘만;이승훈;조승래
    • 한국정밀공학회지
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    • 제13권12호
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    • pp.78-85
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    • 1996
  • The determination of the optimum biarc curve passing through a given set of points along involute curve is studied. The method adopted is that of finding the optimum no. of span and the optimum length of the span such that the error between the biarc curve and involute curve is minimum. Irregular curve span method is effectively used to describe the involute curve with reduced length of NC-Code.

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태양광발전 연계 시스템에 의한 PWM 전류형 인버어터에 관한 연구 (A study on the PWM(pulse witdh modulation) current source Inverter with utility)

  • 황락훈;최호규;신양호;이춘상;김주래;조상로;조문택
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 하계학술대회 논문집 B
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    • pp.1020-1022
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    • 2001
  • because the output of solar cell is direct, it is necessary to install D/A converter system for A.C load, and in case of driving utility line system, it is possible to drive system relation when the system supplies sinusodal current ant voltage having unit power factor. As the characteristics of the soar cell output the is influenced by dailysunight charge, for more electric power it is essential to control the direction toward the san so that the driving point of solar cell can always operate near maximum output point. PWM modulation device among electric power converters must have stable modulation at anytime when it includes noise-factors such as noise-wave and noises on electric voltage wave, a synchronous signal system. In dealing with synchronous signal for control and control signal by microprocessor, it is necessary to compensate it because there is time difference between sample paint and carrier wave. On this papers, single phase PWM current type invertor controled the solar cell having typical voltage dropping character has optimun short current in short, reduces D.C reactance, composes controller for modulation and keeps lower harmonic and high power factor keeping maximum output of solar cell according daily sunlight charge variation.

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청소년의 공격성과 공격희생에 관한연구 (The Study on the Bully/Victim Problems in Korean Junior/Middle Schools)

  • 이춘아
    • 가정과삶의질연구
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    • 제16권3호
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    • pp.67-78
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    • 1998
  • The purpose of this study were 1) to examine the effect of the socio-demographic variables on the adolescent's aggressiveness and victimization, 2)to find the relation among maternal behaviors adolescent's self-esteem aggressive-ness and victimization 3) to analyze the influences of these variables on adolescent's aggressiveness. The subjects were 478 boys and girls attending at junior/middle school in kwang-ju city. Statistics used for data analysis were frequencies means standard deviation Perason's correlation, F-test stepwise multiple regression analysis, major findings were as follows; 1. There were significant differences in Adolescent's aggression and victimiza-tion due to the sex of adolescents and school achievement. 2. There were significant relationships among maternal behaviors adolescents' self-esteem aggression and victimization. 3. The variables influencing adolescent's aggression were maternal authoritarian behavior school achievement the sex of adolescent self esteem and victimization.

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볼스크류 선회형 가공장비의 설계 및 해석에 관한 연구 (A Study on the Analysis and Design for a Ball Screw Whirling Machine)

  • 이춘만;문성호;김은중
    • 한국정밀공학회지
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    • 제34권3호
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    • pp.173-178
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    • 2017
  • Recently, a high-precision ball screw is an essential part of high-speed machines. However, producing high-precision ball screws has been costly and time-consuming. Nowadays, a whirling machine is used to produce high-precision ball screws efficiently. Rotating multi-tips are used to turn the ball screw in the whirling machine. In this study, a structural analysis was performed by a finite-element method to develop a whirling machine. An improved model of the whirling machine was proposed by the analysis. In addition, a thermal analysis was performed to confirm the thermal stability. The results of the analysis can be applied in order to further develop the whirling machine.

고속가공의 표면거칠기 향상에 관한 연구 (A Study on Improvement of Surface Roughness for High Speed Machining)

  • 정종윤;고태조;이춘만;정원지;조혜영
    • 한국산업경영시스템학회:학술대회논문집
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    • 한국산업경영시스템학회 2002년도 춘계학술대회
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    • pp.439-444
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    • 2002
  • Competitive power in manufacturing industries mainly depends on production time and qualify of products. The main issue for achieving this goal is to build high speed and super accuracy machine. The machine has been developed in the aspect of hardware. However, applications in high speed machining is not sufficient to give solutions to industries in machining. This research presents a method to improve surface roughness adopting experimental design. This research finds experimental factors which have great impact on surface roughness. From the experiments cutting conditions are found for better quality of machining.

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고속절삭가공기술개발 (Development of High Speed Machining Technology)

  • 이춘만;최치혁;정원지;정종윤;고태조;김태형
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2002년도 춘계학술대회 논문집
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    • pp.266-272
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    • 2002
  • High-speed machining is one of the most effective technology to improve productivity. Because of the high speed and hugh fried rate, high-speed machining can alive great advantages for the machining of dies and molds. This paper describes on the improvement of machining accuracy in high-speed machining. Depth of cut, feed rate and spindle revolution are control factors. The effect of the control factors on machining accuracy is discussed fur the results of surface roughness and machining error in Z-direction of the high speed machining.

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Automatic Bottle Air Rinser 개발에 관한 연구 (A study on the Development of Automatic Bottle Air Rinser)

  • 이춘만;김대성;김현진
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2004년도 춘계학술대회 논문집
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    • pp.258-262
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    • 2004
  • This study has been focused on the development of automatic bottle air rinser. It is designed to rinse clean empty bottles prior to filling. The bottles are automatically indexed beneath an air nozzle that has both a clean airjet and vacuum source. The bottle is first given a burst of clean air to loosen any particles from the wall of the bottle. A vacuum sequence follows which removes all particulates into a self contained filter unit. In order to the provide the desired function, analysis is carried out by FEM simulation using FLUENT and CATIA software. The final results of analysis are applied to the design of automatic bottle rinser and the machine is successfully developed.

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