• Title/Summary/Keyword: H-Beam

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An Epithermal Neutron Beam Design for BNCT Using $^2H(d,n)^3He$ Reaction

  • Han, Chi-Young;Kim, Jong-Kyung;Chung, Kyu-Sun
    • Nuclear Engineering and Technology
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    • 제31권5호
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    • pp.512-521
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    • 1999
  • A feasibility study was performed to design an epithermal neutron beam for BNCT using the neutron of 2.45 MeV on the average produced from $^2H(d,n)^3$He reaction induced by plasma focus in the z-pinch instead of the conventional accelerator-based $^3H(d, n)^4$He neutron generator. Flux and spectrum were analyzed to use these neutrons as the neutron source for BNCT. Neutronic characteristics of several candidate materials in this neutron source were investigated Using MCNP Code, and $^7LiF$ ; 40%Al + 60%$AIF_3$, and Pb Were determined as moderator, filter, and reflector in an epithermal neutron beam design for BNCT, respectively. The skin-skull-brain ellipsoidal phantom, which consists of homogeneous regions of skin-, bone-, or brain-equivalent material, was used in order to assess the dosimetric effect in brain. An epithermal neutron beam design for BNCT was proposed by the repeated work with MCNP runs, and the dosimetric properties (AD, AR, ADDR, and Dose Components) calculated within the phantom showed that the neutron beam designed in this work is effective in tumor therapy. If the neutron source flux is high enough using the z-pinch plasma, BNCT using the neutron source produced from $^2H(d,n)^3$He reaction will be very feasible.

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고장력강 관재 액압성형 공정 설계 (Hydroforming Process Design of High-Strength Steel Tube)

  • 김기정;김헌영;고형규;신명호
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2009년도 추계학술대회 논문집
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    • pp.202-205
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    • 2009
  • Tubular torsion beam of high strength steel is going about in an automotive rear axle due to the advantages of light weight and efficient rear packaging capability. High strength tubular beam can be manufactured by the hydroforming in order to ensure dimensional accuracy, while a conventional stamping has been used for steel tubular beam. Internal pressure, feeding and their combination are the key factors of controlling the process. Based on the numerical simulation and try-outs, the optimized hydroforming process conditions for the high strength tubular beam were suggested.

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APPLICATIONS OF CRITICAL POINT THEOREMS TO NONLINEAR BEAM PROBLEMS

  • Choi, Q-Heung;Jin, Ying-Hua;Choi, Kyung-Pyo
    • 호남수학학술지
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    • 제29권1호
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    • pp.19-40
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    • 2007
  • Let L be the differential operator, Lu = $u_{tt}+u_{xxxx}$. We consider nonlinear beam equations, Lu + $bu^+$ = j, in H, where H is the Hilbert space spanned by eigenfunctions of L. We reveal the existence of multiple solutions of the nonlinear beam problems by critical point theorems.

PC 기둥-H형강보의 볼트접합부에 관한 실험적 연구 (An Experimental Study on The Bolted Connection Between H-Beam and Precast-Concrete Column)

  • 조은영;박순규
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2003년도 가을 학술발표회 논문집
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    • pp.181-185
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    • 2003
  • The composite structural system with reinforced concrete column and steel beam has some advantages in the structural efficiency by complementing the shortcomings between the two systems. The system, however, has also a lot of problems in earthquake-proof capacity and construction process because it is wet method of construction. So, this paper proposed PCS(Precast Concrete Column and Steel Beam) structural system with dry method of construction. Purpose of this study is to enhance merit and control failure mechanism by installing Dog-Bone on H-beam.

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개구부를 갖는 Web판의 안정해석 (Stability Analysis of Web Plates with Openings)

  • 이수곤;김순철;김명수
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 1998년도 봄 학술발표회 논문집
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    • pp.135-140
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    • 1998
  • The buckling of the perforated web of a simply supported Η-section beam subjected to uniformly distributed load is examined by means of the finite element method. With buckling analysis results, the effect of this hole on the load carrying capacity of the beam with dimensions L/h = 11 and 13 ( L = span length h = web depth) is investigated. The parameters whose variation have been considered are hole size and location. It can be generally concluded that the buckling of the perforated web of an H-section beam is not affected seriously by the location of the perforation.

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T-스티프너 보강 콘크리트충전 각형강관 기둥-H형강 보 접합부의 인장거동 (Tensile Behavior of CFT Column-to-H beam Connections with External T-shaped Stiffeners)

  • 강창훈;신경재;오영석;문태섭
    • 한국강구조학회 논문집
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    • 제14권1호
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    • pp.121-130
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    • 2002
  • This paper presents the tensile behavior of a Concrete-Filled Square Steel Tubular (CFT) column to H-beam welded connections. These connections were externally reinforced with T-shaped stiffeners at the junction of CFT column and beam. The tensile loading tests of eighteen tee-joint connections and finite element analysis using ANSYS were carried out. The main parameters of tests are as follows: 1) the thickness of Square Steel Tubular Column : 6 mm, 9 mm, 2) the strength ratios of tensile strength of horizontal stiffeners to tensile strength of beam flange : 70 %, 100 %, 150 %, 3) the strength ratios of shear strength of vertical stiffeners to tensile strength of beam flange : 80 %, 115 %, 160 %. The results of the tests demonstrate that overall behavior and failure modes of all the specimens are governed mainly by the horizontal stiffeners rather than the vertical stiffeners, and the vertical stiffener played only a role in transferring load introduced from beam to column.

Room-Temperature Luminescence from Ion Beam or Atmospheric Pressure Plasma-Treated SrTiO3

  • Song, J.H.;Choi, J.M.;Cho, M.H.;Choi, E.J.;Kim, J.;Song, J.H.
    • Applied Science and Convergence Technology
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    • 제23권5호
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    • pp.261-264
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    • 2014
  • $SrTiO_3$ (STO) single crystal irradiated with a 3-MeV proton beam exhibits blue and green mixed luminescence. However, the same proton beam when used to irradiate STO with a very thin layer of deposited Pt does not show any luminescence. This Pt layer prevents any damage which may otherwise be caused by arcing, which stems from the accumulated surface voltage of tens of kV due to the charge induced by secondary electrons on the surface of the insulator during the ion beam irradiation process. Hence, the luminescence of ion-irradiated STO originates from the modification of the STO surface layer caused by arcing rather than from any direct ion beam irradiation effect. STO treated with atmospheric-pressure plasma, a simple and cost-effective method, also exhibits the same type of blue and green mixed luminescence as STO treated with an ion beam, as the plasma also creates a layer of surface damage due to arcing.

Reduction of Vacuum Sublimation by Ion Beam Treatment for e-beam Deposited SiC Films

  • Kim, Jaeun;Hong, Sungdeok;Kim, Yongwan;Park, Jaewon
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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    • pp.138.1-138.1
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    • 2013
  • We present the low temperature (${\leq}1,000^{\circ}C$) vacuum sublimation behavior of an e-beam evaporative deposited on a SiC film and a method to reduce the vacuum sublimation through an ion beam process. The density of the SiC film deposited using the e-beam evaporation method was ~60% of the density of the bulk source material. We found that the sublimation became appreciable above ${\sim}750^{\circ}C$ under $1.5{\times}10^{-5}$ torr pressure and the sublimation rate increased with an increase in temperature, reaching ~70 nm/h at $950^{\circ}C$ when the coated sample was heated for 5 h. When the film was irradiated with 70 keV N+ ions prior to heating, the sublimation rate decreased to ~23 nm/h at a fluence of $1{\times}10^{17}\;ions/cm^2$. However, a further increase in fluence beyond this value or an extended heating period did not change (decrease or increase) the sublimation rate any further.

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