• 제목/요약/키워드: Loose part

검색결과 115건 처리시간 0.021초

RPV 상하부에서 발생되는 금속파편의 충격위치 평가

  • 최재원;이일근;송영중;구인수;박희윤
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1997년도 춘계학술발표회논문집(1)
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    • pp.166-171
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    • 1997
  • LPMS(Loose Part Monitoring System)는 원자로 및 냉각재계통내에서 발생하는 금속파편의 검출 및 분석을 위하여 사용되는 진단 장비이다. 본 논문에서는 RPV(Reactor Pressure Vessel)의 상부헤드(closure head)와 하부헤드(lower head)에서의 금속파편의 충격위치를 평가하는 LPMS를 위한 새로운 기법을 제안하고, Mock-up에서의 실험을 통하여 그 효용성을 검증하였다. 즉, 수정된 원교차법을 제안하고, 이를 반구로 모델링된 RPV의 상ㆍ하부헤드에 존재하는 금속파편의 위치평가에 적용하므로써 정확한 충격위치를 찾을 수 있음을 보였다. 이들 결과는 충격물질의 질량이나 에너지를 계산하는데 정확한 정보를 제공해 줄 수가 있다.

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금속파편 충격신호에 대한 Benchmark Data 평가

  • 성게용;오규명;김봉현
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1996년도 추계학술발표회논문집(1)
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    • pp.113-120
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    • 1996
  • 원전 일차계통 내부구조물에 심각한 손상을 유발할 수 있는 금속파편의 탐지 및 진단기술을 비교하고 공유하기 위하여 LPM(loose part monitoring) Benchmark Exercise를 수행하였다. 금속파편 충격에 대한 Benchmark Data는 미국 Catawba Unit 2에서 취득하였으며 6가지 질량의 강구를 다른 높이에서 낙하시킨 36 종류의 data set으로 구성되어 있다. 출격위치 및 강구의 질량을 추정한 결과 실제값과 잘 일치하였고 국내 분석기술의 유용성을 보였으며 외국기술과 비교할 때 동등한 수준임을 확인하였다.

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Innovative Approach to Sintering Aluminum and Aluminum Alloy Powders for Rapid Manufacturing Applications

  • Liu, Jianxin;Kuhn, Howard A.
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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    • pp.246-247
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    • 2006
  • A new approach to sintering loose packed, coarse aluminum alloy powder to full or near full density is presented. A controlled amount of water vapor is introduced into the sintering atmosphere, which disru pts the oxide film and allows metallurgical contact between particles. In addition, supersolidus liquid phase sintering is used to sinter the part to full density. Since the method is particularly applicable to uncompacted powders, it is potentially useful for sintering aluminum powder preforms manufactured by 3DPrinting and powder injection molding.

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다양한 다층 지반모형에 대한 지진동 증폭 (Earthquake Amplification for Various Multi-Layer Ground Models)

  • 정수근;김호연;김대현
    • 지질공학
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    • 제33권2호
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    • pp.293-305
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    • 2023
  • 지진이 발생할 때 대한 지진동 증폭 현상을 확인하기 위해 1g 진동대와 연성토조(Laminar Shear Box, LSB)를 이용하여 모형지반을 조성하였고, 3가지 모델에 대하여 지진동 증폭현상에 대하여 확인하였다. 3가지의 모형지반을 선정하였으며 모든 모형지반에서 조밀한 층과 느슨한 층으로 나누었고, 지반모형의 경우는 다층 수평지반, 다층 제방지반, 다층 분지지반모형으로 선정하였다. 각 지반모형을 제작하며 가속도계 매설을 진행하였으며, 인공지진파, Sinesweep파와 Sine 10 Hz의 지진파를 통하여 증폭현상을 확인하였다. 최대지반가속도(Peak ground acclelration, PGA)와 응답스펙트럼 가속도(Spectrum acceleration, SA)를 통해 지진동 증폭현상을 확인하였다. 수평 다층지반에서 조밀한 지반을 통과 후 느슨한 지반에서 가속도 증폭이 조밀한 지반에 비해 크게 발생하는 것을 확인할 수 있었으며, 다른 두 모형지반에서는 층의 경계면을 통과 후 점차 중심부에서 가속도 증폭이 더 크게 발생하는 것을 확인할 수 있었다.

접합부 수밀성 향상 시트를 이용한 복합방수 공법에 관한 연구 (A Study on complex waterproofing Method Using Part of Joint Watertightness Improved Sheet)

  • 서우일;김수련;곽규성;오상근
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2004년도 학술대회지
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    • pp.1-6
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    • 2004
  • We ensure a flat and regular basic surface by using part of joint waterproofing improved sheet method applying the upper slab of a concrete structure. We solve the problem of getting loose scale the general sheet by waterproofing of the sheet and improving adhesive strength of the basic concrete. Also, waterproofing sheet union to problem of joint have solved using of insertion type method so that, it improved a watertightness. It has improved in resist impact, resist abrasion and it is the effect of shortened construction period and cutting down on construction expenses. Here are the special quality and superiority of this waterproofing research. (1) Level material has the super adhesive strength so that it makes the basic surface without the gab of waterproofing sheet and waterproofing layer with the string adhesive strength. (2) We unite the sheet with the joining part between sheets by waterproofing sheet joint using of method. (3) There is the effect of shortened construction period and cutting down on construction expenses without waterproofing of protection.

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20대 여성의 기성복 재킷 부위별 선호핏(fit)에 영향을 미치는 요소 분석 - 여대생집단과 패션모델집단 간 비교를 중심으로 - (The Analysis of Factors Influencing Fit by Ready-made Jacket Part preferred by Women in Twenties - Focusing on the Comparison between Female College Student Group and Fashion Model Group)

  • 하선주;강여선;최혜선
    • 한국생활과학회지
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    • 제23권6호
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    • pp.1171-1189
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    • 2014
  • In order to provide the basic data for creating the environment which can efficiently reflect prefer fit along with body size when selecting clothes size in the indirect purchasing environment, this study analyzed the difference of ready-made jacket part-specific fit preferred by fashion models in their twenties and female college students. This study was to analyze the impact of body size, recognition of body part-specific characteristics shape, body satisfaction on prefer fit of jacket. As for the difference of prefer fit depending on the body size, female college students preferred more loose fit than models. The difference according to recognition of body part-specific characteristics shape turned out to be significant for prefer fit depending on the degree of bend of neck, arm length, bend of back recognition and matching fit was found to be preferred as they recognize their body shape to be normal and the difference according to body satisfaction appeared to be significant in the terms of bend of back, hip width/protrusion, torso size/length, sleeve length, whole body shape and they turned out to prefer matching fit as they are satisfied with their body. As shown above, body size, recognition of body part-specific characteristics shape, especially body satisfaction have a great influence on prefer fit of jacket and therefore, if preparing for a size selection step according to body shape and satisfaction in the jacket size selection process, customers' satisfaction in jacket size may be improved and it is considered to be helpful for both consumers and sellers.

한국산 쓸종개, Plotosus lineatus (Thunberg) 수염의 조직 (Histology of the Barbels of Striped Sea Catfish, Plotosus lineatus (Thunberg))

  • 박인석;설동원;김은미;김영자;이영돈
    • 한국수산과학회지
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    • 제38권3호
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    • pp.158-163
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    • 2005
  • This paper deals with the histology of the barbels of striped sea catfish, Plotosus lineatus (Thunberg). This fish have eight noticeable barbels of two pairs on their maxillary and mandibular. Each barbel is composed of an epidermis, dermis and a central rod of cartilage. The epidermis in the middle part of the maxillary barbel is thicker than those on other parts, and formed of stratified epithelium which contains many cutaneous taste buds and a few small club cells. Number of taste buds increase on the middle and posterior part of each barbel. The dermis consists of loose connective tissue fibers which encloses blood vessels and bundles of nerve fibers. The barbels of this fish can be categorized into stiff and flexible types and are accessory, feeding and sensory structures. Thus we substantiate that they are gustatory receptor organs for this fish.

스노우보드 웨어에 대한 착용 실태조사 연구 (Research on the Actual Condition of Snowboard Wear)

  • 류신아;박길순
    • 복식문화연구
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    • 제11권5호
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    • pp.721-736
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    • 2003
  • As for the purposes of the research: First, on the wearers of snowboard wear on the market, I intend to investigate contents related with purchase, price, brand, style, etc., and grasp requirements and complaints. Second, I intend to know the evaluations of users according to itemized questions on the snowboard wear on the market. Third, I like to provide basic materials by investigating itemized requirements for the development of snowboard wear. On the male & female snowboarders on a skiing ground, I carried out a preliminary investigation in December, 2001, and a main investigation from January to February, 2002. The results are as follows: 1. Many of them purchased imported quality goods, and the rate purchase was high between 20~25 year. Loose two-piece suits of different colors were preferred. The most uncomfortable part proved to be a neck part. 2. The degree of general satisfaction with the snowboard wear on the market was 4.60. And in terms of itemized evaluation, dissatisfaction was found in Clothing construction, facility of laundry and handling, price and brand rather than in style, fiber composition and tactile sensation. 3. In the investigation of the requirements in case of snowboard wear development, the most common requirement was the facility of action. I believe this should be met by study on the choice of pertinent margin and the pattern development.

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기계공업 종사자의 작업복 착용 실태조사 연구 (A Research of Worker's Uniform in the Mechanical Industry)

  • 김혜령;서미아
    • 복식문화연구
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    • 제10권6호
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    • pp.718-734
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    • 2002
  • The purpose of this study is to provide basic data f3r improvement in Working Uniform in both scientific and efficient ways. The study were enforced by questionnaire and personal interview. The subject of the survey were the workers of 264 in mechanic industry in Seoul. The results obtained from the researches by methods above are as follows. 1. In general, Working Uniform could be classified types of two. One is loose-fitting one-piece garment covering the body and legs, the other is two-piece garment. The latter is a jacket with either sports collar or soutein collar, fastened with either buttons or a zipper and its sleeve is finished by cuffs and tapes. Regarding to color. inkblue, dark navy, khaky, dark beige are favourable ones. 2. In regard to the necessity of uniform that workers suppose, most of them were aware of it and agreed wearing uniform could play an important part. The reason why are on the basis of safety-first and work efficiency and also to protect a body from harmful or toxic dirt specially in machinery workplace. 3. The purpose of wearing an uniform according to statistics of population make some difference in age, gender. categories of industry, and the scale of factory. 4. In regard to care of uniform, front hem, edge of sleeve in a jacket, and knee, hip part in pants were most vulnerable spots for dirt. The parts damaged easily are edge of sleeve in a jacket and a zipper in pants. On the average, laundry have been done by water and was once a week frequency.

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장방형 침전지에서 길이에 따른 슬러지 floc의 형태에 관한 연구 (Morphological Parameters of the Sludge Flocs in a Long Rectangular Secondary Settling Tank)

  • 김영철;이진우;강민기
    • 한국물환경학회지
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    • 제22권3호
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    • pp.468-474
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    • 2006
  • In the secondary settling tanks, three different types of settling phenomena occurs; i.e., zone settling for sludge thickening in the bottom part of settling tank, and discrete and flocculent settling for clarification in the upper part. In this paper, morphological parameters of the floc in sludge blanket layers along the length of a long rectangular tank were investigated. The plant used for this study had a serious bulking problem caused by Microthrix parvicella. Floc size decreased as the surface area of settling tank increases, which indicates that in the secondary settling tank where zone settling believed to be predominant, free or flocculent type of settling contributes to floc size distributions. Large floc particles deposit in the front zone of settling tank, but small and loose flocs mostly in the zone near its outlet. On the other hand, filament length contained in one gram of sludge blanket solid increases along the flow direction. Large flocs with less filaments settle faster, but small flocs having more filaments result in poor settling. These results support function of microorganism selection occurring in secondary settling tank. In addition, designing a long rectangluar settling tank with double hoppers might be one of the ways of bulking control, but this idea has to be verified with a further study.