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Recent Trends of Lithographic Technology (반도체 공정용 리소그래피 기술의 최근 동향)

  • Chung, T.J.;You, J.J.
    • Electronics and Telecommunications Trends
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    • v.13 no.5 s.53
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    • pp.38-52
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    • 1998
  • Phase-shifting masks (PSM), optical proximity correction (OPC), off-axis illumination (OAI), annular illumination (AI)의 리소그래피 분해능 향상 기법과 deep ultraviolet photoresist의 개발 및 리소그래피의 최근 기술 동향을 요약 소개한다. DUV 리소그래피의 대안으로 관심을 끌고 있는 scattering with angular limitation projection electron-beam lithography (SCALPEL), extreme ultraviolet lithography (EUVL), X-ray lithography (XRL), ion projection lithography (IPL) 등의 새로운 리소그래피 기술들의 기본 원리와 최근 기술 동향도 소개하였다. 리소그래피는 반도체 공정에 있어서 가장 중요한 부분을 차지하기 때문에 리소그래피의 최근 기술 동향을 검토해 봄으로써 국내 리소그래피 장비 산업의 기술 개발을 위한 방향 설정에 도움이 될 것으로 생각한다.

An Analysis of Bending Behavior of Continuous P.S.C Girder Railway Bridge by Using Down-Up Method (주형의 하강ㆍ상승을 이용한 연속 P.S.C빔 철도교의 휨거동 해석)

  • 구민세;위영민;최인식
    • Proceedings of the KSR Conference
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    • 2001.10a
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    • pp.293-298
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    • 2001
  • 2span continuous Prestressed concrete girder railway bridges, span length 21m, 25m, 30m, 35m, that down-up method is applied and that designed to satisfy service load in accordance with design criteria of railway bridge can be dropped in their hight compared with existing simply supported prestressed concrete girder railway bridges. Continuous bridges result in guaranteeing safety against bending behavior by loading the practical railway moving load with each velocity. But the natural frequency of span length 21m is estimated not to satisfy recommended limitation of UIC 776-1R..

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A Study on Pressure Variation of the Passenger Cabin of Conventional Train for Speed-up (기존선 속도향상을 위한 객실내 압력변동에 관한 연구)

  • 남성원;한기흥
    • Proceedings of the KSR Conference
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    • 2000.11a
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    • pp.521-526
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    • 2000
  • Experimental study is conducted to clarify pressure variation of the passenger cabin of conventional train. These pressure variation may give rise to the ear-discomfort. Generally ear-discomfort has been considered as a problem related to high speed train. Because there is also a good progress to speed-up for conventional line, this isn't only a phenomena related to high speed train any longer. In this study, tile pressure variation of interior, gangway and exterior of saemaeul passenger car is measured using the atmospheric pressure sensors in Honam line. From the results of experiment, the pressure variation per second almost close in upon the limitation in the case of Noryong tunnel. Therefore, to accomplish speed-up for conventional train, it may be necessary to study a serial ventilating and the airtightness of carbody.

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Analysis of Short Grinding Effect on Removing of Surface Irregularities of Rail Welding Joint (레일용접부 요철 제거의 국부연마 효과 분석)

  • Woo, Byoung-Koo;Lee, Syeung-Yeol;Kim, Myung-Soo;Lee, Sung-Uk
    • Proceedings of the KSR Conference
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    • 2010.06a
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    • pp.684-691
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    • 2010
  • Rail is one of major track components for train service, it should be provided in the condition of flat and smooth driving aspect. Therefore, it is inevitable that there would be the field welding to integrate on CWR(Continuous Welded Rail) removing rail joint in these days. It is high chance to be some rail surface irregularity due to the limitation on the status of work condition If a high speed train runs on the rail surface irregularity in the welding part, big impact load comes to pass on that, so track irregularity cycle is reduced, therefore track maintenance cost can be increased. this paper has analyzed wheel load variation according to removing the rail surface irregularity using portable grinding machine in the high speed line. The result measured before and after in the field is decreased about 9.26% on the wheel load variation.

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Sound Insulation Performance of the Panel Structures in High Speed Train: Transmission Loss of the Corrugated and Extruded Panels (고속철도 차음구조의 차음성능: 주름 및 압출재의 투과손실)

  • Kim, Seock-Hyun;Paek, In-Su;Kim, Jeong-Tae
    • Proceedings of the KSR Conference
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    • 2007.11a
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    • pp.82-89
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    • 2007
  • Sound transmission characteristics are investigated on the corrugated steel and aluminium extruded panels used for railway vehicles. Sewell-Sharp-Cremer(SSC) model, equivalent orthotropic plate model and equivalent mass law are applied to predict the sound transmission loss. The predicted values of the sound transmission loss are compared with the measured values. The reliability and the limitation of the prediction models are investigated. For the corrugated panels and honeycomb panels, the coincidence and local resonance severely deteriorate the sound insulation performance around the corresponding frequency bands. The result of the study shows that the equivalent orthotropic plate model and the SSC model can be used as good prediction models, if the coincidence frequency or local resonance frequency is correctly applied.

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Noise Reduction of Traction Motor for High Speed Train (고속전철용 견인전동기 소음개선)

  • Kim, Jung-Chul;Kim, Dea-Kwang;Kim, Bong-Chul;Park, Yeong-Ho;Choi, Jong-Mook
    • Proceedings of the KSR Conference
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    • 2007.11a
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    • pp.95-100
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    • 2007
  • The traction motor for High Speed Train is being required reliability and stability for high-speed operation. And also required low noise level, high performance, compact size owing to the space and weight limitation for attaching to train, etc. As a result of requiring the low noise level and high power capacity, it is adopted forced-air-ventilation insead of self-ventilation that is generally used on electric multiple unit. Traction motor is cooled by cooling air through the air-ventilation hole. When the traction motor is operated with forced-air-ventilation, there is some abnormal noise in the specific RPM. This paper is dealing with the method to reduce the resonance phenomena by adopting the rotor blade.

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Reuse Methods of Treated Sewage for securing Water Resource in Busan (부산시 수자원 확보를 위한 하수처리수 재이용 방안)

  • Kim, Jung-Bae;Moon, Seung-Gun;Park, Yool
    • Proceedings of the SAREK Conference
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    • 2009.06a
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    • pp.1232-1237
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    • 2009
  • Recently, we often encounter water shortage problem due to drought during dry season. Although we have built dams and expanded our tap water system greatly to meet the increasing demand of water, this approach has its inherent limitation including environmental destruction in the course of the dam construction. Therefore, this paper is aimed to analyze the water recycling models developed in other countries and modify them to fit into our system. Also the water recycling system in Busan municipal area was analyzed to propose an alternative method for reusing the recycled water from wastewater treatment area.

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Development of a new digital photogrammetric technique for characterization of rock joint orientation

  • Kim Jaedong;Kim Jong-Hoon
    • 한국지구물리탐사학회:학술대회논문집
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    • 2003.11a
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    • pp.60-65
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    • 2003
  • A new algorithm was developed to interpret joint orientations from a pair of images of the rock slope to overcome the limitation of photographing direction as in the parallel stereophotogrammetric system and to maximize the range of image measurement. This algorithm can be regarded as a modified multistage convergent photographing system. To determine camera parameters in the perspective projection equation that are the major elements in the photogrammetric technique, a new concept was developed by using three ground control points and single ground guide point. This method could be considered to be very simple when compared with other existing methods which use a number of ground control points and complicated analysis processes.

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A Study on the Driver's Aptitude Standard with the Side of Human Engineering (인간공학적 측면에서 본 운전자의 적성에 관한 연구)

  • 현영기
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.2 no.2
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    • pp.111-114
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    • 1979
  • Human Engineering is the new science that studies tile function and the characteristic of human. It is purpose to design machine equipments for him to be able to manipulate those, exactly, safely and easily. This study will introduce that new science in traffic problems and will be done as follows. 1. The Presentation of Problems: 2. Human Engineering and Accurrence process of traffic accidents. 3. Human Engineering and aptitude analysis 4. Conclusion In this paper, driver is not the man who drives a car, is the man who is able to adapt himself to road, and traffic environment. There is a limitation in Human faculty, especially, in the power of attention. Therefore, this paper will be studied to show that it is seeking the ability needed by traffic analysis as well as getting ability of aptitude to attribute to prevention of traffic accidents.

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Mitigation of Flooding under Externally Imposed Oscillatory Gas Flow

  • Lee, Jae-Young;Chang, Jen-Shih
    • Proceedings of the Korean Nuclear Society Conference
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    • 1995.10a
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    • pp.475-479
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    • 1995
  • During the hypothetical loss of coolant accident in the nuclear power plant the emergency core cooling water could not penetrate to the reactor core when the steam flow rate from the reactor core exceeds CCFL (Countercurrent flow limitation). The CCFL generated by earlier investigators are developed under the steady gas flow. However the flow instability in the reactor loop could generate oscillatory steam flow, hence their applicability under oscillating flow should be investigated. In this work, an experimental investigation of countercurrent flow in the vertical flow channel has been conducted under oscillatory gas flow. Pulsation of gas under oscillatory flow disturbs the flow pattern significantly and prevents flooding (CCFL) when its minimum value is less than the threshold gas flow rate value.

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