• 한국재료학회:학술대회논문집
• /
• 한국재료학회 1997년도 한국재료학회 춘계학술발표회
• /
• pp.46-46
• /
• 1997

• 한국재료학회:학술대회논문집
• /
• 한국재료학회 2004년도 춘계학술발표대회 및 제6회 신소재 심포지엄
• /
• pp.71-71
• /
• 2004

• 한국세라믹학회지
• /
• 제35권11호
• /
• pp.1212-1221
• /
• 1998

• 한국콘텐츠학회:학술대회논문집
• /
• 한국콘텐츠학회 2018년도 춘계 종합학술대회 논문집
• /
• pp.225-226
• /
• 2018

높은 청년실업은 오늘날 여러 곳에서 갖가지 사회문제를 유발하고 있다. 본 연구는 청년고학력자들의 실업문제와 관련 지역대학의 역할과 활용에 대하여 분석하고 청년고학력 실업에 대한 방안을 모색하고자 한다.

• 한국초전도학회:학술대회논문집
• /
• 한국초전도학회 2005년도 High Temperature Superconductivity Vol.XV
• /
• pp.70-70
• /
• 2005

• 한국전기전자재료학회논문지
• /
• 제11권11호
• /
• pp.1014-1021
• /
• 1998

We evaluated the effect of processing variables on microstructural evolution interface irregularity between Ag sheath and superconductor core and resultant critical current density(J$_{c}$) of (Bi,Pb)$_2$Sr$_2$Ca$_2$Cu$_3$O$_{x}$(2223) superconductor tape. The value of J$_{c}$ was significantly influenced by the interface irregularity, degree of texturing and relative 2223 content. The interface became more irregular(sausage effect), while the degree of texturing gradually improved as the dimension of tape decreased during forming process. As the dimension of wire/tape were changed from diameter of 3.25 mm to thickness of 0.20 mm, J$_{c}$ value was observed to be increased by 10 times. In addition, optimum sintering temperature for improved J$_{c}$ was observed to be 835$^{\circ}C$ in a ambient atmosphere probably due to combined effect of both improved texturing and high 2223 content. Microstructural investigation showed the degree of texturing was degraded by the existence of both second phases and interface irregularity. It was observed that larger grain size and better texturing was developed near relatively flat interface compared to those inside superconducting core.ting core.

• 한국정밀공학회지
• /
• 제19권6호
• /
• pp.96-103
• /
• 2002

The objective of this study is to adjust the roll gap fur the dimension accuracy of bar in hot bar rolling process considering roll wear. In this study hot bar rolling processes fur round and oval passes have been investigated. In order to predict the roll wear, the wear model is reformulated as an incremental from and then wear depth of roll is calculated at each deformation step on contact area using the results of finite element analysis, such as relative sliding velocity and normal pressure at contact area. Archard's wear model was applied to predict the roll wear. To know the effects of thermal softening of DCI (Ductile Cast Iron) roll material according to operating conditions, high temperature micro hardness test is executed and a new wear model has been proposed by considering the thermal softening of DCI roll expressed in terms of the main tempering curve. The new technique developed in this study for adjusting roll gap can give more systematically and economically feasible means to improve the dimension accuracy of bar with full usefulness and generality.

• 대한교통학회:학술대회논문집
• /
• 대한교통학회 1995년도 한-중 국제학술회의 발표논문
• /
• pp.51-59
• /
• 1995

본문재이달성진해금후도시객운교통적발전응주족우대용량、쾌원환유궤지공신적기출 진,종분석,해기유철로추뉴선재성시범권내적력장포국화현실공능유충,탐계료철로추뉴선재학보상항대외대교통주요공능적전제하,위괄응본해도시교통발전적수요,여하통과알 잠개조,재객경,밀집、류향매녕、원정교장적지구,장부분기유지면철로선개조성고가유궤 성시쾌속전혹,절실퇴해승차난적모순,촉진도시교통향현대화방향발전작출핵만.

• 한국소성가공학회:학술대회논문집
• /
• 한국소성가공학회 2004년도 춘계학술대회 논문집
• /
• pp.27-30
• /
• 2004

Clad wire , which has the advantages of the high strength of a steel core and the electro-conductivity, corrosion resistance of a copper layer, is widely being used the telecommunications, electric-electronic and military technology industries, among others. It is important to obtain uniform coated rate when producing clad wires. Clad wire drawing process can be influenced on damage and coated rate of core and sleeve by process variables as semi-die angle and reduction in area. Therefore, in this study, the finite-element results established in previous study is used to analyze the effect of the various forming parameters, which included the semi-die angle, reduction in area etc. The coated rate will be predicted with observation copper coated rate variation according to total reduction in area and the optimal pass schedule will be set up through proper reduction in area and semi-die angle variation.

• 대한기계학회논문집A
• /
• 제26권9호
• /
• pp.1736-1745
• /
• 2002

The objective of this study is to predict the roll wear in hot rod rolling process. In this study hot rod rolling process for round and oval passes has been investigated. In order to predict the roll wear, the wear model is reformulated as an incremental form and then wear depth of roll is calculated at each deformation step on contact area using the results of finite element analysis, such as relative sliding velocity and normal pressure at contact area. Archard's wear model was applied to predict the roll wear. To know the thermal softening of DCI (Ductile Cast Iron) roll according to operating conditions, high temperature micro hardness test is executed and a new wear model has been proposed by considering the thermal softening of DCI roll expressed in terms of the main tempering parameter curve. 3D wear program developed in this study might be used for adjusting the gap of rolls to set up a suitable rolling schedule for keeping dimensional tolerance of the product.