• 제목/요약/키워드: Junior engineering

검색결과 430건 처리시간 0.028초

유동층 반응기에서 회중석 정광의 염소화반응 (Chlorination of the scheelite concentrate in a fluidized bed reactor)

  • 엄명헌;박용성;이철태
    • 공업화학
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    • 제4권3호
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    • pp.591-600
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    • 1993
  • 염소화에 의한 텅스텐 추출 공정의 공업화를 위해 유동층 반응기에서 회중석의 염소화반응이 조사되었다. 본 실험의 모든 결과는 텅스텐 성분이 유동충 반응기에서 성공적으로 염소화됨을 보여주었다. 본 실험의 적정 조건은 다음과 같다. : 반응온도 $900^{\circ}C$, 반응시간 : 20 min, 염소가스 유속 : 13.2cm/sec 그리고 회중석에 대한 petroleum coke의 무게비 : 0.2 또한 회중석과 petroleum coke의 평균 직경은 각각 $150.5{{\mu}m}$ 그리고 $750.9{{\mu}m}$이다. 이러한 조건하에서 회중석 중의 텅스텐 성분이 95% 이상이 염소화되었다.

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폴리머-시멘트 모르타르의 강도와 내구성 (The Strength and Durability of Polymer-Cement Mortars)

  • 황의환;황택성;오하마 요시히코
    • 공업화학
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    • 제5권5호
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    • pp.786-794
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    • 1994
  • 폴리머-시멘트 모르타르의 강도와 내구성에 대하여 검토하였다. 폴리머-혼화제로서 styrene-butadiene rubber(SBR) 라텍스, ethylene-vinyl acetate(EVA) 에멀젼 및 polyacrylic ester(PAE) 에멀젼을 사용하고, 폴린머-시멘트 비를 다양하게 변화시켜(5, 10, 15, 20 wt%) 공시체를 제작하였다. 내구성의 평가시험으로는 동결융해시험, 내산성시험 및 내열성 시험을 수행하였다. 폴리머-시멘트 모르타르의 내동해성은 폴리머-시멘트비가 증가될수록 현저히 향상되었으나 내산성과 내열성은 저하되었다. SBR 폴리머-시멘트 모르타르의 강도(압축 및 휨강도)는 폴리머-시멘트비가 증가될수록 향상되었으나 EVA 및 PAE 폴리머-시멘트 모르타르는 폴리머-시멘트비 10wt%에서 최대치를 나타내었다.

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모델 기준 적응 퍼지 제어기를 이용한 DC 전동기 제어 (DC Servo Motor Control using Model Reference Adaptive Fuzzy Controller)

  • 손재현;김제홍
    • 전자공학회논문지T
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    • 제36T권4호
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    • pp.60-70
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    • 1999
  • 본 논문에서는 FLC의 적응능력에 대한 단점과 제어규칙 도출의 어려움을 극복하기 위하여 모델기준 적응 퍼지제어기(MRAFC)를 제안하였다. MRAFC는 단순퍼지제어기와 플랜트로 구성된 내부 피드백 루프와 단순 퍼지제어기의 제어규칙을 동조시키는 외부 루프로 구성된다. 기준모델은 기준입력에 대해 전체 제어시스템에 요구되는 제어성능을 특성화하고 수량화하는 퍼지제어기 설계기준으로 사용되었다. 그리고 적응 매카니즘은 FLC 제어규칙을 동조하는 역할을 수행한다. 제안한 알고리즘의 성능은 DC 서보 전동기에 대한 실험에 의해 검증되었다.

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바나듐 함유 MFI형 제올라이트의 제조 및 촉매적 특성 (Preparation and Catalytic Properties of Vanadium-Containing MFI Type Zeolite)

  • 김건중;고완석;조병린
    • 공업화학
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    • 제5권2호
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    • pp.361-372
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    • 1994
  • 수열합성법 및 탈알루미늄 처리 이후 $NH_4VO_3$담지법으로 바나듐이 함유된 MFI형 제올라이트를 제조하였다. X선 회절분석, 시차 열분석, 적외선 분광분석 및 전자스핀공명분석을 수행하여 바나듐의 격자구조 내로의 도입을 검토하였다. 탈알루미늄된 ZSM-5에 $NH_4VO_3$를 담지시키고 소성한 경우에도 수열합성법으로 제조한 시료와 같이 바나듐이 구조 내로 도입될 수 있었다. 제올라이트 구조 중의 바나듐은 고온처리에 의해 산화-환원과정을 거칠 수 있으며, 이들은 원자단위로 분산되어 고정됨을 나타내었다. 벤젠 수산화반응과 hexane 및 알코올의 산화반응을 바나듐 함유 MFI형 제올라이트의 특성 검토를 위한 시험반응으로 이용하였다.

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대학의 연구실 안전관리를 위한 연구활동 종사자의 안전의식 차이에 관한 연구 - 일반대학, 전문대학, 폴리텍대학 - (A study on the difference in safety awareness of research employees working for laboratory safety management of university institutes - University, Junior College, Polytechnic Colleges-)

  • 권윤아;권영국
    • 대한안전경영과학회지
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    • 제17권3호
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    • pp.89-96
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    • 2015
  • The study was conducted with statical analysis of data (828 data in 2010, 752 data in 2012, 648 data in 2014) in order to evaluate laboratory awareness difference of research employees working in different types of universities. Results of the study were as follows: First, university institutes in the order of polytechnic colleges, university, and junior college showed the highest laboratory safety awareness in 'awareness and education of laboratorial safety regulation' and 'awareness in laboratory risk factors'. Second, the difference in safety awareness of universities by year(years that conducted current status survey) was the highest in year 2014, then in 2010, and in 2008. Third, the difference of research employees working for laboratory safety management by year(years that conducted current status) showed that university had the highest laboratory safety awareness in year 2010, but it changed to polytechnic colleges in year 2012 and 2014. Through this study, we could recognize the difference in safety awareness of research employees working in university institutes.

의료기기 안전성 정보 모니터링에 대한 한병병원 및 병원 종사자의 인지도 조사연구 (A Study on the Cognizance of Hospital and oriental Hospital Workers for Medical Device Safety Information Monitoring)

  • 김지현;남기창;김호준;남연교;김유진;조은혜;권범선
    • 대한의용생체공학회:의공학회지
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    • 제42권3호
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    • pp.86-93
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    • 2021
  • Purpose: The purpose of this study is to find out the cognizance of medical device safety information (MDSI) monitoring in the hospital and oriental hospital workers, and the different aspect of MDSI between oriental medical devices and medical devices. Methods: The survey was performed both in the oriental medicine hospital and general hospital. The survey had 16 items; 2 items basic questions, 5 items in the awareness of MDSI, 5 items in the education of MDSI, 4 items in the necessity of defining oriental medical devices and differences between general and oriental medical devices. A total of 120 hospital worker were participated; 60 oriental medicine hospital workers and 60 general hospital workers. They had worked in the oriental medicine or general hospital associated with 'Medical Device Safety Monitoring Center, Dongguk University Ilsan Hospital' in 2019 and 2020. Results: The cognizance of MDSI was high both in oriental medicine hospital and general hospital workers and there were no significant differences between oriental medicine and general hospital workers. When we divided the hospital workers into the senior workers who had worked for over 3 years and junior workers for less than 3 years, the senior workers had higher awareness of MDSI than junior workers. However, the cognizance of education of MDSI was high which was not different between senior and junior workers. Both hospital workers thought that it was necessary to define oriental medicine device legally and the oriental medical device might have low risk and less side effect than medical device. Conclusion: The cognizance of MDSI was high and there was no significant differences between oriental medicine and general hospital workers. Because the senior hospital workers had higher recognition of MDSI, we need to provide the continuous education program for junior hospital workers. Although oriental medical device are thought to be safer than medical device, we need to have a legal definition.

Quality Attributes of Winning Products in the Korean Market

  • Son Eun-Il;Park Young-Taek
    • 한국품질경영학회:학술대회논문집
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    • 한국품질경영학회 1998년도 The 12th Asia Quality Management Symposium* Total Quality Management for Restoring Competitiveness
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    • pp.31-36
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    • 1998
  • 250 winning products from 1985 to 1997 in the Korean market were examined in order to find that what kind of product attributes have been major determinants of commercial success in the market. The major determinants are different with product categories. For example, function has been the most important determinant in electric home appliances, while portability has been the most important in telecommunication products. The results will be a cue to the future direction of new product development.

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Viscoplastic analysis of thin-walled tubes under cyclic bending

  • Pan, Wen-Fung;Hsu, Chien-Min
    • Structural Engineering and Mechanics
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    • 제7권5호
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    • pp.457-471
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    • 1999
  • In this paper, different curvature-rates are controlled to highlight the characteristic of viscoplastic response in cyclic bending tests. The curvature-ovalization apparatus, which was designed by Pan et al. (1998), is used for conducting the curvature-controlled experiments on thin-walled tubular specimens for AISI 304 stainless steel under cyclic bending. The results reveals that the faster the curvature-rate implies, the fast degree of hardening of the metal tube. However, the ovalization of the tube cross-section increases when the curvature-rate increases.

스위칭에 의한 전동기 써지전압 분포 (The Analysis of Surge distribution for motor by Switching)

  • 김종겸;이은웅;조현길;백두현
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1996년도 하계학술대회 논문집 A
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    • pp.115-117
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    • 1996
  • The electrical stress, which is generated by switching devices, has been affected by various kinds of factors such as surge impedance, motor capacity, surge wavefront and so forth. In this study, the surge phenomenon delivered into motor winding in switching was analyzed with actual system.

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A Study on IFGP Model for Solving Multiobjective Quality Management under Fuzzy Condition

  • Cheong, Jong Shik;Pak, Pyong Ki
    • 품질경영학회지
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    • 제21권2호
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    • pp.194-214
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    • 1993
  • This paper purports to study on interactive fuzzy goal programming model which leads to the compromise solution which the decision maker satisfies through the interactive approach. We also attempted to calculate local proxy preference function from utility function of sum-of-logarithms in connection with marginal rate of substitution and interactive approach for the purpose of applying weight of multiobjective function. In an attempt to grasp compromise solution from fuzzy efficient solution, we decided to take the interactive method and presented stopping rule for this.

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