• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2000년도 춘계학술강연 및 발표대회 강연 및 발표논문 초록집
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• pp.9-10
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• 2000

An important business-field of world-wide steel-industry is the coating of thin metal-sheets with zinc, zinc-aluminum and aluminum based materials. These products mostly go into automotive industry. in particular for the car-body. into building and construction industry as well as household appliances. Due to mass-production, the processing is done in large continuously operating plants where the mostly cold-rolled metal-strip as the substrate is handled in coils up to 40 tons unwind before and rolled up again after passing the processing plant which includes cleaning, annealing, hot-dip galvanizing / aluminizing and chemical treatment. In the liquid Zn, Zn-AI, AI-Zn and AI-Si bathes a combined action of corrosion and wear under high temperature and high stress onto the transfer components (rolls) accounts for major economic losses. Most critical here are the bearing systems of these rolls operating in the liquid system. Rolls in liquid system can not be avoided as they are needed to transfer the steel-strip into and out of the crucible. Since several years, ceramic roller bearings are tested here [1.2], however, in particular due to uncontrollable Slag-impurities within the hot bath [3], slide bearings are still expected to be of a higher potential [4]. The today's state of the art is the application of slide bearings based on Stellite\ulcorneragainst Stellite which is in general a 50-60 wt% Co-matrix with incorporated Cr- and W-carbides and other composites. Indeed Stellite is used as the bearing-material as of it's chemical properties (does not go into solution), the physical properties in particular with poor lubricating properties are not satisfying at all. To increase the Sliding behavior in the bearing system, about 0.15-0.2 wt% of lead has been added into the hot-bath in the past. Due to environmental regulations. this had to be reduced dramatically_ This together with the heavily increasing production rates expressed by increased velocity of the substrate-steel-band up to 200 m/min and increased tractate power up to 10 tons in modern plants. leads to life times of the bearings of a few up to several days only. To improve this situation. the Mechanical Alloying (MA) TeChnique [5.6.7.8] is used to prOduce advanced Stellite-based bearing materials. A lubricating phase is introduced into Stellite-powder-material by MA, the composite-powder-particles are coated by High Energy Milling (HEM) in order to produce bearing-bushes of approximately 12 kg by Sintering, Liquid Phase Sintering (LPS) and Hot Isostatic Pressing (HIP). The chemical and physical behavior of samples as well as the bearing systems in the hot galvanizing / aluminizing plant are discussed. DependenCies like lubricant material and composite, LPS-binder and composite, particle shape and PM-route with respect to achievable density. (temperature--) shock-reSistibility and corrosive-wear behavior will be described. The materials are characterized by particle size analysis (laser diffraction), scanning electron microscopy and X-ray diffraction. corrosive-wear behavior is determined using a special cylinder-in-bush apparatus (CIBA) as well as field-test in real production condition. Part I of this work describes the initial testing phase where different sample materials are produced, characterized, consolidated and tested in the CIBA under a common AI-Zn-system. The results are discussed and the material-system for the large components to be produced for the field test in real production condition is decided. Outlook: Part II of this work will describe the field test in a hot-dip-galvanizing/aluminizing plant of the mechanically alloyed bearing bushes under aluminum-rich liquid metal. Alter testing, the bushes will be characterized and obtained results with respect to wear. expected lifetime, surface roughness and infiltration will be discussed. Part III of this project will describe a second initial testing phase where the won results of part 1+11 will be transferred to the AI-Si system. Part IV of this project will describe the field test in a hot-dip-aluminizing plant of the mechanically alloyed bearing bushes under aluminum liquid metal. After testing. the bushes will be characterized and obtained results with respect to wear. expected lifetime, surface roughness and infiltration will be discussed.

• 한국환경교육학회지:환경교육
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• 제21권1호
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• pp.82-96
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• 2008

이 연구의 주요한 목적은 환경교육과 학생의 진로 발달을 고찰하는데 있으며, 구체적인 연구목적은 그들의 진로 전망 인식, 진로 준비 과정, 대학의 진로발달지원을 이해하는데 있다. 대부분의 대학생에게 학교를 다니는 주요한 목적은 진로를 준비하는 것이지만 대학의 교육은 그들이 원하는 직업을 얻기에 충분하지가 않다. 전공이 특정한 진로경로를 가지고 있지 않거나 또는 전공이 특정한 진로경로를 가지고 있지만 흡족하고 질 높은 직업을 제공하지 않을 때 진로 준비는 더 복잡해진다. 학부 환경교육과 프로그램이 최근의 전형적인 예이다. 학부 환경교육과 학생들과 그들을 둘러싼 환경을 이해하기 위해 2007년 8월 17일부터 8월 20일까지 인스턴트 메신저를 통해 항구대학교(가칭) 환경교육과 학부, 졸업생 6명에 대하여 반구조화된 인터뷰를 실시하였다. 인터뷰는 연구 참여자 한 사람 당 $1{\sim}2$회, 1회 2시간 정도 개별적으로 실시하였다. 연구의 결과는 다음과 같다. 첫째, 그들은 진로 전망, 진로 결정에 대한 긍정적인 태도를 가지고 있었지만 잘 발견되지는 않았다. 두 번째, 진로 탐색, 진로준비는 개인적으로 수행되며, 학교는 많은 체계적인 진로 지원을 제공하지 않고 있었다. 세 번째, 프로그램의 교과과정과 그들의 미래진로는 관련을 보이지 않았다. 이 연구의 결과로부터 대학에서 진로 발달과 관련된 몇 가지 주요한 함의가 도출되었다. 첫 번째, 환경교육과 프로그램의 학부 학생들은 전공과 관련된 직업 기회의 탐색으로부터 직업 탐색 스킬의 개발에 이르기까지의 종합적인 진로 발달 지원이 필요한 것으로 보인다. 특히 경험적인 진로 탐색이 환경교육이 자신의 적성과 흥미에 적합한지를 이해하는데 도움이 되는 것으로 보인다. 두 번째, 이들 학생들을 위한 진로 발달 지원은 대학교 저학년부터 실시해야 한다. 세 번째, 이들 학생들은 다른 학문적 영역뿐만 아니라 그들의 전공과 관련된 다양한 기회를 탐색하는 데 있어서 도움을 필요로 할 것이다.

• 한국학교ㆍ지역보건교육학회지
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• 제6권
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• pp.17-34
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• 2005

The purpose of this study was to examine the sex-consciousness and sexual values of school children by geographic region. It's specifically attempted to make a comparative analysis of sex-consciousness and sexual values between urban and rural elementary schoolers to help provide efficient sex education for them to build the right sexual values. The subjects in this study were 400 elementary schoolers in their sixth year of elementary schools located in Danyang-gun and Chungju city, north Chungcheong province. After a survey was conducted, answer sheets from 387 students that were analyzable were analyzed. For data handling, SPSS program was employed, and t-test was utilized to see if there's any differences between the urban and rural elementary school youngsters in sex consciousness and sexual values. And $x^2$ test was used to make a comparative analysis of their view of sex education. The findings of the study were as follows : First, regarding sex-consciousness, they had general knowledge on sex. Especially, they were highly aware of sexual violence and the generation of baby, but many of them didn't know about where and how egg cells were produced. This indicated that systematic education should be offered in various ways. Concerning geographic gap, there was a significant difference in sexual knowledge between the urban and rural students. As to sexual attitude, they took a relatively positive attitude toward display of affection or sex-related talk on TV or in movies, as they viewed it as natural. This finding implied that the elementary schoolers were recipient toward sex and took an active attitude toward sexual expressions. Concerning geographic gap, there was no difference between the rural and urban students. As for sexual practices, the largest group of the students had a liking for the opposite sex, which showed that their needs for sex were unveiled in the course of having some trouble due to the other sex rather than through firsthand experiences or activities. As to geographic gap, there was a significant difference between the urban and rural students in that regard. Besides, the urban students put their sex-consciousness in practice more often than the rural students did. After they are educated to build the right sexual values, systematic sex-education programs should also be offered for them to be exposed to sustained sex education and to team how to apply their sex-consciousness to real life. Second, as for sexual values, the school children had relatively positive and equalitarian sexual values. Regarding geographic gap, there were significant gaps between the two groups' view of the opposite sex, sexual roles and chastity. Concerning view of the opposite sex, they attached more importance to the inner aspects of the opposite sex than his or her look, and they wanted to date in a natural manner. Regarding sexual roles, they were relatively well cognizant of gender equity and the importance of male and female roles. As to view of chastity, they looked upon sex as natural, not as what's ugly or ashamed of. Third, concerning their outlook on sex education, approximately more than half the students felt the needs for sex education, and there was a significant difference between the urban and rural students. They wanted to receive education about the prevention of sexual violence and physical changes during puberty the most, and there was a significant gap between the urban and rural students in this aspect. As to the time for sex education, they thought that students should start to be exposed to sex education in their fifth or sixth year. This finding signified that fifth or sixth graders who were in the beginning of puberty started to have a lot of interest in their own physical changes. Therefore, sex education would produce better effects when it's provided to fifth or sixth graders. Nearly half them preferred single-gender class when they received sex education, and there's no gap between the urban and rural students in that regard.