• Title/Summary/Keyword: Engineering calculation

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A Thermodynamic Analysis on Silicon Consumption during The Chemical Vapper Deposition of Tungsten (텅스텐의 화학증착시 Si소모에 관한 열역학적 분석)

  • 정태희;이정중
    • Journal of Surface Science and Engineering
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    • v.23 no.1
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    • pp.27-33
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    • 1990
  • Thermodynamic analysis on silicon consumpton during the chemical vapor deposition of tungten was carried out by calculation equilibrium concerations of all possible product species utilizing a computer progrom according to VCS.(Villars-Cruise-Smith) algorithm. The calculation could show various reaction paths which dominate the tungsten deposition under different process conditions. According to the calculation, the consumption of silicon can also be reduced at a lower total pressure SiH4 without H2 as the reacting gas is most effective for suppression of the excessive consumption of silicon during the deposition process.

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Energy band structure calculation of crystalline solids using meshfree methods (무요소법을 이8한 결정고체의 에너지 띠 구조 계산)

  • 전석기;임세영
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2002.10a
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    • pp.623-628
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    • 2002
  • A meshfree formulation for the calculation of energy band structure is presented. The conventional meshfree shape function is modified to handle the periodicity of Bravais lattice, and applied to the calculation of real-space electronic-band structure. Numerical examples include the Kronig-Penney model potential and the empirical pseudopotentials of diamond and zinc-blonde semiconductors. Results demonstrate that the meshfree method be a promising one as a real-space technique for the calculations of diverse physical band structures.

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A Evaluation of Calculation Method for Temperature Distribution of Hot Water Pipe with Changing Flow Rate (유량변화를 고려한 온수배관의 온도분포 계산법평가에 관한 연구)

  • Suh, S.J.;Choi, C.H.
    • Solar Energy
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    • v.19 no.3
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    • pp.53-61
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    • 1999
  • We already presented new calculation method about the temperature distribution in hot water pipe flow of the unsteady condition. In this paper, we introduce consequence of the case study to confirm appropriation of the calculation method, and case study performs to establish actual hot water use supposed two model that is; the CWV(constant water volume) and VWV(variable water volume).

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A Calculation Method for Temperature Distribution of Hot Water Pipe under Unsteady Condition (비정상조건하의 온수배관의 온도분포에 관한 수치계산법 연구)

  • Choi, C.H.;Suh, S.J.
    • Solar Energy
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    • v.19 no.3
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    • pp.13-21
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    • 1999
  • Calculation method about the water temperature variable inside hot water pipe had proposed in the past does not correspond with branch pipe system, variable of water volume, variable of entrance water temperature, using and so on. A calculation method proposed in this paper can solve above problems, and calculate the kinds variation of the water temperature inside pipe in the real use state of the hot water pipe.

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En-Route Trajectory calculation using Flight Plan Information for Effective Air Traffic Management

  • Kim, Yong-Kyun;Jo, Yun-Hyun;Yun, Jin-Won;Oh, Taeck-Keun;Roh, Hee-Chang;Choi, Sang-Bang;Park, Hyo-Dal
    • Journal of Information Processing Systems
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    • v.6 no.3
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    • pp.375-384
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    • 2010
  • Trajectory modeling is foundational for 4D-Route modeling, conflict detection and air traffic flow management. This paper proposes a novel algorithm based Vincenty's fomulas for trajectory calculation, combined with the Dijkstra algorithm and Vincenty's formulas. Using flight plan simulations our experimental results show that our method of En-route trajectory calculation exhibits much improved performance in accuracy.

Deflection calculation method on GFRP-concrete-steel composite beam

  • Tong, Zhaojie;Song, Xiaodong;Huang, Qiao
    • Steel and Composite Structures
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    • v.26 no.5
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    • pp.595-606
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    • 2018
  • A calculation method was presented to calculate the deflection of GFRP-concrete-steel beams with full or partial shear connections. First, the sectional analysis method was improved by considering concrete nonlinearity and shear connection stiffness variation along the beam direction. Then the equivalent slip strain was used to take into consideration of variable cross-sections. Experiments and nonlinear finite element analysis were performed to validate the calculation method. The experimental results showed the deflection of composite beams could be accurately predicted by using the theoretical model or the finite element simulation. Furthermore, more finite element models were established to verify the accuracy of the theoretical model, which included different GFRP plates and different numbers of shear connectors. The theoretical results agreed well with the numerical results. In addition, parametric studies using theoretical method were also performed to find out the effect of parameters on the deflection. Based on the parametric studies, a simplified calculation formula of GFRP-concrete-steel composite beam was exhibited. In general, the calculation method could provide a more accurate theoretical result without complex finite element simulation, and serve for the further study of continuous GFRP-concrete-steel composite beams.

A spent nuclear fuel source term calculation code BESNA with a new modified predictor-corrector scheme

  • Duy Long Ta ;Ser Gi Hong ;Dae Sik Yook
    • Nuclear Engineering and Technology
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    • v.54 no.12
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    • pp.4722-4730
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    • 2022
  • This paper introduces a new point depletion-based source term calculation code named BESNA (Bateman Equation Solver for Nuclear Applications), which is aimed to estimate nuclide inventories and source terms from spent nuclear fuels. The BESNA code employs a new modified CE/CM (Constant Extrapolation - Constant Midpoint) predictor-corrector scheme in depletion calculations for improving computational efficiency. In this modified CE/CM scheme, the decay components leading to the large norm of the depletion matrix are excluded in the corrector, and hence the corrector calculation involves only the reaction components, which can be efficiently solved with the Talyor Expansion Method (TEM). The numerical test shows that the new scheme substantially reduces computing time without loss of accuracy in comparison with the conventional scheme using CRAM (Chebyshev Rational Approximation Method), especially when the substep calculations are applied. The depletion calculation and source term estimation capability of BESNA are verified and validated through several problems, where results from BESNA are compared with those calculated by other codes as well as measured data. The analysis results show the computational efficiency of the new modified scheme and the reliability of BESNA in both isotopic predictions and source term estimations.

A Study on the Calculation of Maintenance Factor(MF) of Tunnel Lighting in Expressway Considering the Actual Installation and Maintenance Conditions (실제 설치 및 유지보수 조건을 고려한 고속도로 터널조명 보수율 산정 연구)

  • Lee, Min-Wook;Park, Kwang-Yong;Kim, Pil-Young;Park, Yong-Jin;Kim, Hoon
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.27 no.3
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    • pp.7-15
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    • 2013
  • In lighting design, the calculation of maintenance factor is performed by calculation considering light source, characteristics of luminaire and environmental factors. The method to calculate the current maintenance factor applied to tunnel lighting design takes into consideration only pollution factors in tunnels. In addition, the calculation method should be change in response to changes of tunnel conditions and used light sources. In this study, the calculated factor of the maintenance factor in tunnel is determine by four calculation factors generally applied to the calculation of maintenance factor. This study examined the method of calculating the maintenance factor of tunnel lighting that can be applied according to the installation conditions in designing tunnel lighting by applying the actual installation data of luminaire.

Guided Wave Calculation and Its Applications to NDE

  • Hayashi, Takahiro
    • Journal of the Korean Society for Nondestructive Testing
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    • v.24 no.2
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    • pp.125-135
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    • 2004
  • This paper describes the calculation technique for guided wave propagation with a semi-analytical finite element method (SAFEM) and shows some results of numerical calculation and guided wave simulation for plates, pipes and railway rails. The SAFEM calculation gives dispersion curves and wave structures for bar-like structures. Dispersion curve software for a pipe is introduced, and also dispersion corves for a rail are given and experimentally verified. The mode conversions in a plate with a defect and in a pipe with an elbow or a defect are shown as examples of our guided wave simulations.