• 제목/요약/키워드: expanding

검색결과 4,853건 처리시간 0.031초

원자력 증기발생기 튜브/튜브시트 확관방법별 특성평가 (The Evaluation of Tube to Tubesheet Joint Part on Nuclear S/G)

  • 심상한;배강국;김인수
    • 대한용접접합학회:학술대회논문집
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    • 대한용접접합학회 1996년도 특별강연 및 춘계학술발표 개요집
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    • pp.34-37
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    • 1996
  • The expanding method of tube to tubesheet joint part on neclear steam generators are classified into three classes of roller expanding, explosive expanding and hydraulic expanding. After the expanded Mock-Up specimen are made by the three expanding method. The general properties, microstructure/microvickers hardness, pull-out strength, hydraulic leak pressure, of tube to tubesheet joint part were inspected. and We evaluated the operation efficiency of expansion, reproduction of expanded joint about three expanding method. Through the overall evaluation of tube to tubesheet joint part, The hydraukic expanding and explosive expanding could be certificated more useful expanding method.

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지속가능한 소비생활 확산을 위한 방안 고찰 (A Study on the Plans for Expanding Sustainable Consumption)

  • 윤정혜;이희숙
    • 한국지역사회생활과학회지
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    • 제12권2호
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    • pp.61-73
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    • 2001
  • The purpose of this paper was to study the plans for expanding sustainable consumption. Three plans for expanding sustainable consumption were discussed. That is, 1) the plans for expanding consumer awareness of sustainable consumption, 2) for constructing green infra-structure over the country, and 3) for driving economic motives of sustainable consumption were discussed in detail.

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유전자 알고리즘과 신경회로망을 이용한 고속 확관기의 확관속도 최적화 (Optimization of Expanding Velocity for a High-speed Tube Expander Using a Genetic Algorithm with a Neural Network)

  • 정원지;김재량;김진한;홍대선;강홍식;김동성
    • 한국공작기계학회논문집
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    • 제14권2호
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    • pp.27-32
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    • 2005
  • This paper presents the optimization of expanding velocity for tube expanding process in the manufacturing of a heat exchanger. In specific, the expanding velocity has a great influence on the performance of a heat exchanger because it is a key variable determining the quantity of tube expending at assembly stage as well as a key Parameter determining overall production rate. The simulation showed that the genetic algorithm used in this paper resulted in the optimal tube expanding velocity by performing the following series of iteration; the generation of arbitrary population for tube expanding parameters, consequently the generation of tube expanding velocities, the evaluation of tube expanding quantity using the pre-trained data of plastic deformation by means of a neural network and finally the generation of next population using a penalty faction and a Roulette wheel method.

Expanding-cell 유한차분법의 마이크로스트립-도파관 변환기에의 적용 (Application of Expanding-cell FDTD Method to Microstrip-to-Waveguide Transition)

  • 강희진;최재훈
    • 한국전자파학회논문지
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    • 제11권3호
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    • pp.345-351
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    • 2000
  • 본 논문에서는 Ka 대역 마이크로스트립 도파관 변환기를 설계하고, Expanding-cell 시간 영역 유한 차분법을 이용하여 변환기의 주파수 특성을 분석하였다. 마이크로스트립 도파관 변환기의 구조는 릿지(ridge)형 도파관, 마이크로스트립 라인, 그리고 $\lambda$/4 체비쉐프 도파관 임피던스 변환기로 이루어졌다 .. Expanding-cell 유한차분 방법을 마이크로스트립-도파관 변환기의 $\lambda$/4 체비쉐프 도파관 임피던스 변환기의 해석에 이용하여 계산의 정 확성과 효율성을 높였다. 계산 결과를 측정치와 비교하여 정확성을 입증하고, 균일한 크기의 미세 셀(fine cell) 과 성긴 셀(coarse cell)을 이용한 결과와 비교하여 효율성을 입증하였다 .. 4단과 3단 체비쉐프 도파관 임피던스 변환기의 주파수 특성을 비교하여 단의 수와 대역폭과의 관계를 분석하였다.

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EXPANDING MEASURES FOR HOMEOMORPHISMS WITH EVENTUALLY SHADOWING PROPERTY

  • Dong, Meihua;Lee, Keonhee;Nguyen, Ngocthach
    • 대한수학회지
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    • 제57권4호
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    • pp.935-955
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    • 2020
  • In this paper we present a measurable version of the Smale's spectral decomposition theorem for homeomorphisms on compact metric spaces. More precisely, we prove that if a homeomorphism f on a compact metric space X is invariantly measure expanding on its chain recurrent set CR(f) and has the eventually shadowing property on CR(f), then f has the spectral decomposition. Moreover we show that f is invariantly measure expanding on X if and only if its restriction on CR(f) is invariantly measure expanding. Using this, we characterize the measure expanding diffeomorphisms on compact smooth manifolds via the notion of Ω-stability.

인더스트리 4.0시대에서 전자무역을 활용한 중소기업 수출 확대 방안 (A Plan on Expanding Export of Small Businesses Using e-Trading Application in Industrie 4.0)

  • 송계의
    • 무역상무연구
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    • 제78권
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    • pp.53-72
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    • 2018
  • Recently, it has been known that it need to be solved export marketing on expanding export of Small Business Commodity. Therefore, the purpose of this paper is to analyse on expanding export of Small Business Commodity through e-Trading Application in Industrie 4.0. This study deals with the terms of three connection success factors on expanding export of Small Business Commodity through e-Trading Application in Industrie 4.0 which are a firm's subjective factors, a industrial environment factors, and a governmental policy factors. According to analysis results of the three success factors, a firm's subjective factors(4.13 score) are scored at the most ones of the three success factors, to be compared with a industrial environment factors(3.89 score), with a government policy factors(3.72 score). Therefore, first of all, it is important to expanding export of Small Business Commodity through e-Trading Application in Industrie 4.0 through as follows, a firm's subjective factors : (1) to procure concentrated market strategy and real market capacity, (2) to procure speedy satisfaction of customer needs and confidence, (3) to procure ability of export marketing through e-Trading Application, (4) to enhance export expanding strategy coincided in Industrie 4.0. And, the next, we have to expanding export of Small Business Commodity through e-Trading Application in Industrie 4.0 through considering a industrial environment factors and a government policy factors.

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고온 증기를 이용한 잎담배의 팽화연구 (Method for expanding tobacco leaves with steam at high temperature and velocity)

  • 김병구;김기환;정한주;유광근;이태호
    • 한국연초학회지
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    • 제17권1호
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    • pp.68-78
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    • 1995
  • A study of expanding tobacco includes the steps of adjusting the moisture content of cut tobacco, without the use of exogenous impregnants by contacting the filler with a high velocity gaseous medium at elevated temperature such that heat is rapidly and substantially uniformly transferred from the medium to the filler for a total contact time sufficient to expand the tobacco leaves. Study is disclosed for drying and expanding cut tobacco by introducing the tobacco into an elongated tubular shaped conduit through which steam high temperature 150-35$0^{\circ}C$ and high velocity above the 18m1sec, super steam is recycled. moisture content of shreded tobacco leaves, immediately before treatment within the range of from 10% to 24% and, most preferably, within the range of from 18% to 21%. Expanding rate showed 70% in NC -82(B.3) and 42% in Burley -21(B.1) which is produced in 1993 under this condition. When expanding tobacco expanded tobacco did not change significally, but they were decreased at 27$0^{\circ}C$ very largely. The curtailment of cost price and physical and chemical properties of various items were improved in cigarettes. Key words : Expanding tobacco, Super steam tobacco expansion, Fast drying tobacco, High temperature treat tobacco, Puffing tobacco.

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유리연마슬러지를 사용한 다공성 소재의 미세구조 및 물리적 특성에 관한 연구 (Microstructure and Physical Properties of Porous Material Fabricated from a Glass Abrasive Sludge)

  • 추용식;권춘우;이종규;심광보
    • 한국세라믹학회지
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    • 제43권5호
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    • pp.277-283
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    • 2006
  • A porous material with a surface layer was fabricated from glass abrasive sludge and expanding agents. The glass abrasive sludges were mixed with expanding agents and compacted into precursors. These precursors were sintered in the range of $700-900^{\circ}C$ for 20 min. The sintered porous materials had a surface layer with smaller pores and inner parts with larger pores. The surface layer and closed pores controlled water absorption. As the expanding agent fraction and the sintering temperature increased, the porosity and pore size increased. The porous materials with $Fe_2O_3$ and graphite as the expanding agents had a low absorption ratio of about 3% or lower while the porous material with $CaCO_3$ as the expanding agent had a higher absorption ratio and more open pores.

중국 영토공정에 관한 대응방안 연구 (A Study on the Countermeasures for China's Territory Expanding)

  • 신용우;오원규
    • 지적과 국토정보
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    • 제44권1호
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    • pp.37-59
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    • 2014
  • 중국이 우리 영토인 '구려벌'을 그들의 영토로 만들기 위해 동북공정을 필두로 한 영토공정을 실시하고 있는 것에 대해, 중국 영토공정의 원인과 목적 및 실태를 분석하고 그에 대한 대응 방안을 제시함으로써 잃어버린 우리 영토를 수복하는 데 본연구의 목적이 있다. 이를 위해서 본 연구에서는 중국이 실시하는 영토공정에 대해 세부적으로 검토했다. 중국이 실시하는 영토공정인 동북공정과 단대공정, 탐원공정과 요하문명론은 물론 근대공정까지 실시하게 된 원인과 목적을 밝히고 그 내용을 점검하고 실태를 분석하여 문제점을 지적한 후 그에 대한 대응 방안을 제시했다. 중국은 영토공정을 실시하기 위해서 무엇보다 문화와 역사를 왜곡하였다. 따라서 본 연구에서도 문화와 역사적인 측면에서 중국이 주장하는 왜곡의 실태를 파악하고 그 모순을 짚어서 맞대응하는 방법을 택함으로써 차별성을 가졌다. 아울러 본 연구에서는 중국의 역사와 문화 왜곡은 물론 우리 스스로 중국이 주장하는 것들을 각기 딴 생각으로 해석하는 잘못을 지적하였다. 또 우리 영토를 지키는데 정부의 적극적인 대응이 매우 중요하다는 점을 강조하였다.