• 제목/요약/키워드: tubes

검색결과 3,118건 처리시간 0.028초

내부 구속 중공 CFT 교각의 연성도 평가 (Ductility Evaluations of Internally Confined Hollow CFT Column)

  • 김현종;염응준;한택희;강영종
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2007년도 정기 학술대회 논문집
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    • pp.683-687
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    • 2007
  • Internally Confined Hollow-Concrete Filled Tube(ICH-CFT) column which has two tubes on both side of concrete, inner tube and outer tube perform great seismic abilities, ductility and absorption of energy, by the tubes and the hollow pmt. So this study does qualitative analysis about seismic capacities depending on parameters diameter of column, hollow ratio, thickness of tubes - by moment-curvature analysis.

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온도 및 압력상승에 따른 동/황동 라디에터 튜브의 변형 (Deformation of the Tubes in Copper/Brass Radiator with Rise of Temperature and Pressure)

  • 정명진
    • 한국안전학회지
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    • 제8권4호
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    • pp.16-20
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    • 1993
  • The combined effect of increased pressure/temperature and the reduced material thicknesses act to increase the stress on the radiator componets. The design life of the radiator is influenced by the cyclic stresses and corrosion, which act to weaken the materials, radiator mechanical failure occurs when a tube or solder Joint ruptures, causing coolant loss or insufficient heat rejection. Therefore, in this study, through strain measurement of the tubes in copper/brass radiator, the strain distribution of the tubes in radiator as function of temperature and pressure is obtained.

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강관 유도 광휘 열처리 시스템 개발에 관한 연구 (A Study on the Development of Induction Bright Annealing System for Stainless Steel Welded Pipe & Tubes)

  • 신완호;배종수;이주석
    • 연구논문집
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    • 통권22호
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    • pp.97-105
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    • 1992
  • This study aimed to develop the heat treating equipment which could produce austenitic stainless steel welded pipes & tubes maintaining its peculiar brightness even after heat treatment. The results of this study are as follows:- Development of 8.5kHz, 150kw bright annealing system was achieved. - Bright annealing of austenitic stainless steel welded pipes & tubes was performed by the developed pilot-system through this study and heat-treatment effects were quite successful in viewpoint of surface brightness, hardness distribution, microstructure, removal of residual stress, strength and corrosion resistance.

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Junctional Neurulation : A Junction between Primary and Secondary Neural Tubes

  • Kim, Kyung Hyun;Lee, Ji Yeoun
    • Journal of Korean Neurosurgical Society
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    • 제64권3호
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    • pp.374-379
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    • 2021
  • Recent case reports of junctional neural tube defect (JNTD) which is a peculiar type of spinal anomaly showing the functional disconnection of the primary and secondary neural tubes has risen interest in the process of junctional neurulation (the connection between the two neural tubes) during development. This article summarizes the clinical features of the JNTD and reviews the literature on the basic research on junctional neurulation.

Recent Discovery of Secondary Mineral Deposits in an Idaho Lava Tube

  • Kesner, David W.
    • 동굴
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    • 제4호
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    • pp.33-39
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    • 1996
  • Secondary mineral deposits of gypsum, mirabilite, thenardite, crisobolite have long been known and, in fact, are quite common in lava tubes of southwest Idaho. Until recently, calcium carbonate were found in a few tubes in very small amounts and were thought to be qu are. The recent ‘rediscovery’ of Helen's Hidden Hide - Away lava tube h significantly changed this thinking. The deposits in this lava tube are only quite extensive but extremely varied in structure. As this is a v recent discovery, only basic preliminary work will be presented in t paper. It is hoped this will stimulate intrest for further and more inte study of the lava tubes of southwestern Idaho.

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관표면에서의 곡면응축막의 열전달 (Condensation Heat Transfer to Rivulets of Condensate on Horizontal tubes)

  • 배순훈;최영순
    • 대한설비공학회지:설비저널
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    • 제4권1호
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    • pp.18-22
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    • 1975
  • A simple analysis has been made of the condensation of vapor onto rivulets of condensate which are formed by non-wetting narrow Taflon strips circumferencially located in a certain interval on horizontal tubes. Heat transfer to the rivulets increased over $50\%$ above that to the Nusselt uniform thickness film. Results are directly applicable to condenser tubes in large steam condensers.

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Recent Discovery of secondary Mineral Deposit in an Idaho Lava Tube

  • Kesner, David W.
    • 동굴
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    • 제5호
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    • pp.70-78
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    • 1997
  • Secondary mineral deposits of gypsum, mirabilite, thenardite, and cristpbolite have long been known and, in fact, are quite common in the lava deposits tubes of southwest idaho. Until recently, calcium carbonate were only found in a few tubes in very small amounts and were though to be quite rare. The recent ‘rediscovery’ of Henlen's Hidden Hide -A way lava tube has significantly changed this thinking. The deposits in the lava tube are not only quite extensive but extremely varied in structure. As this is a very recent discovery, only basic preliminary work will be presented in this paper. It is hoped this will stimulate interest for further and more intensive study of the lava tubes of southwestern idaho.

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Tenuidraconema koreensis, a New Species of Marine Nematodes (Adenophorea: Desmodorida) from South Korea

  • Rho, Hyun-Soo;Kim, Won
    • Animal cells and systems
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    • 제8권3호
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    • pp.155-163
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    • 2004
  • Tenuidraconema koreensis, a new species of free-living marine nematodes, collected from the subtidal coarse sediments and various invertebrates of Namae, is described. The new species differs from T. fiersi Decraemer, 1989, the only other species in the genus, by having the combination of the following characters: the position of twelve cephalic adhesion tubes in both sexes (anterior six cephalic adhesion tubes inserted on the rostrum and posterior six inserted on the body annules), and the number of posterior sublateral adhesion tubes (12 in male and 13 in female) and posterior subventral adhesion tubes (15 in male and 19 in female). This paper contains the description of the new species with illustrations and scanning electron microscope (SEM) photomicrographs. This is the first discovery of the monotypic genus Tenuidraconema outside the type locality.

결함을 가진 증기발생기 U-튜브의 진동특성 (Vibration Characteristics of Steam Generator U-tubes with Defect)

  • 조종철;정명조;김웅식;김효정;김태형
    • 한국소음진동공학회논문집
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    • 제13권5호
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    • pp.400-408
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    • 2003
  • This paper investigates the vibration characteristics of steam generator (SG) U-tubes with defect. The operating SG shell-side flow field conditions for determining the fluidelastic instability parameters such as added mass are obtained from three-dimensional SG flow calculation. Modal analyses are performed for the U-tubes either with axial or circumferential flaw with different sizes. Special emphases are on the effects of flaw orientation and size on the modal and instability characteristics of tubes, which are expressed in terms of the natural frequency, corresponding mode shape and stability ratio. Also, addressed is the effect of the internal pressure on the vibration characteristics of the tube.

WEAR BEHAVIOUR OF STEAM GENERATOR TUBES IN ROOM TEMPERATURE WATER

  • Lee, Young-Ho;Kim, Hyung-Kyu;Kim, In-Sup
    • 한국윤활학회:학술대회논문집
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    • 한국윤활학회 2002년도 proceedings of the second asia international conference on tribology
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    • pp.203-204
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    • 2002
  • The wear behaviour of steam generator (SG) tubes (Inconel 600 and 690) against support materials (405 and 409 ferritic stainless steels) has been experimentally studied in room temperature water using reciprocating wear apparatus with tube-an-plate configuration. The results showed that the wear rate of Inconel 690 was lower than that of lnconel 600 with increasing normal loads and sliding amplitudes. Also, plastic deformation layers appear below the surface of both SG tubes, which have a specific thickness and are small compared with their grain size. This means that wear rate of SG tubes in water condition is closely related to the formation and fracture of plastic deformation layers.

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