• Title/Summary/Keyword: Theoretical equation

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A Study on the Vertical Distributions of the Concentration in Suspended Sedimentations (부유유사의 연직농도분포에 관한 연구)

  • 유시창;김희종
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.24 no.4
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    • pp.80-91
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    • 1982
  • To precict the suspended sediments which are 80% of total sediments in a flood disch- arge, an equation representing vertical distribution of sediment concentration was derived based upon the diffusion theory and the logalithmic velocity distribution function in the tubulent flow mechanism. The hypothesis that the uniform mass transfer is occurred at upper part along the center line of water depth, was established as a preconition to solve the problem. The theorecal and the observed values were compared. And the theoretical equation was modified to be fit the theoretical values the observed values. Observed results are as follow; 1) Equation 12) is the theoretical equation representing the vertical concentration distri- bution of suspended sedimenta 2) Rous&exonential type vertical concentration distribution equation shows signification errors near the water surface. But the equation 12) shows substation cocentration values near the water surface. 3) Equation 15) is the modified theoretical equation which is possible to predict the vertical concentration distribution of suspended sediments.

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Solution of Klein Gordon Equation for Some Diatomic Molecules with New Generalized Morse-like Potential Using SUSYQM

  • Isonguyo, Cecilia N.;Okon, Ituen B.;Ikot, Akpan N.;Hassanabadi, Hassan
    • Bulletin of the Korean Chemical Society
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    • v.35 no.12
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    • pp.3443-3446
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    • 2014
  • We present the solution of Klein Gordon equation with new generalized Morse-like potential using SUSYQM formalism. We obtained approximately the energy eigenvalues and the corresponding wave function in a closed form for any arbitrary l state. We computed the numerical results for some selected diatomic molecules.

A Study on the Determination of Wave Load Acting on Offshore Structures (해저 석유개발을 위한 해양구조물의 기본 설계/해석 및 실험기법 개발 -해양구조물에 작용하는 파랑하중 산정에 관한 연구)

  • 이근무
    • Journal of Ocean Engineering and Technology
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    • v.14 no.1
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    • pp.6-10
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    • 2000
  • In this paper various methods of determining of wave loads acting ofshore structures including impact load due to breaking wave are studied and corresponding model test was performed. In the theoretical approach wave load by nonbreaking wave and impact load by breaking wave is determined by Morrison's equation Goda's equation and impact wave equation, In the experimental approach wave load by nonbreaking wave acting on cylindrical pile used in offshore structures is determined by measuring the strain on a cylindrical pile and compared with theoretical calue. in the numerical approach impact load by breaking wave acting on a modeled cylindrical pile is calculated by usign ANSYS FEM program and compared with theoretical value. It is found that the experimental and numerical results are comparable to theoretical results, Thus the determination of wave load acting on offshore structures can be obtained by a proposed methods and it acceptable.

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Prediction and Analysis of Fracture Strength for Surface Flawed Laminates (표면 손상을 입은 적층판의 강도 예측 및 분석)

  • Choi D. H.;Hwang W.
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 2004.04a
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    • pp.275-278
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    • 2004
  • In this paper, the fracture strength of the surface damaged laminates was predicted by applying the fracture strengths of the unflawed and flawed laminates. For prediction, the theoretical equation about the fracture strength of laminates was simplified applying classical laminate theory and was applied to the surface damaged laminates. Lagace's and Tsai's experimental data were used for verifying the theoretical equation. Moreover, to verify the theoretical prediction, an experiment was performed. Surface unflawed laminate and flawed laminates were fabricated and the experiments were made and these results were compared with theoretical predictions. The specimens' fiber direction was same to the tensile direction and the theoretical predictions and the experimental results were showed good agreement. Therefore, by this equation, the fracture strength of structures made of composites will be able to be predicted when the surface of the structures was damaged.

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Derivation of Current-Voltage Equation for OLED using Device Simulation

  • Lee, Sang-Gun;Hattori, Reiji
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.1212-1215
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    • 2009
  • The theoretical equations for J-V characteristics in an OLED was derived according to the internal carrier emission equation based on a diffusion model at Schottky barrier contact and the mobility equation based on the Pool-Frenkel model. The J-V characteristics of OLED are presented using a behavioral model for analog systems (Verilog-A language), and the accuracy of this model was verified by comparing with the device simulation results.

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A New Accurate Equation for Estimating the Baseline for the Reversal Peak of a Cyclic Voltammogram

  • Oh, Sung-Hoon;Chang, Byoung-Yong
    • Journal of Electrochemical Science and Technology
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    • v.7 no.4
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    • pp.293-297
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    • 2016
  • Here we propose a new equation by which we can estimate the baseline for measuring the peak current of the reverse curve in a cyclic voltammogram. A similar equation already exists, but it is a linear algebraic equation that over-simplifies the voltammetric curve and may cause unpredictable errors when calculating the baseline. In our study, we find a quadratic algebraic equation that acceptably reflects the complexity included in a voltammetric curve. The equation is obtained from a laborious numerical analysis of cyclic voltammetry simulations using the finite element method, and not from the closed form of the mathematical equation. This equation is utilized to provide a virtual baseline current for the reverse peak current. We compare the results obtained using the old linear and new quadratic equations with the theoretical values in terms of errors to ascertain the degree to which accuracy is improved by the new equation. Finally, the equations are applied to practical cyclic voltammograms of ferricyanide in order to confirm the improved accuracy.

Theoretical Analysis of Charging Current of Linear Type Magnetic Flux Pump According to the Penetrated Position and Moving Speed of Magnetic Flux (침투자속의 위치와 이동속도에 따른 리니어형 자속펌프 충전전류의 이론적 해석)

  • Chung, Yoon-Do;Bae, Duck-Kweon;Yoon, Yong-Soo;Ko, Tae-Kuk
    • Progress in Superconductivity and Cryogenics
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    • v.11 no.1
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    • pp.39-44
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    • 2009
  • We proposed a linear type magnetic flux pump (LTMFP) as a power supply for superconducting magnet system. In order to explain the operating mechanism of pumping action, the pumping sequence based on penetrated position and moving speed of magnetic flux on the superconducting Nb foil should be understood. In this paper, we induced a theoretical equation for pumping current of LTMFP according to the position of normal spot and corresponding equivalent circuit. In addition, current charging tendencies under the intensity of magnetic flux and frequency were described based on the theoretical pumping equation.

Prediction of Thermal Fatigue Life of Alumina ceramics (알루미나 세라믹스의 열피로 수명 예측)

  • 정우찬;한봉석;이홍림
    • Journal of the Korean Ceramic Society
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    • v.36 no.8
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    • pp.871-875
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    • 1999
  • Theoretical equation to calculate thermal fatigue life was derived in which slow crack growth theory was adopted. The equation is function of crack growth exponent n. Cyclic thermal fatigue tests were performed at temperature difference of 175, 187 and 200$^{\circ}C$ respectively. At each temperature difference critical thermal fatigue life cycles of the alumina ceramics were 180,37 and 7 cycles. And theoretical thermal fatigue life cycles were calculated as 172, 35 and 7 cycles at the same temperature difference conditions. Therefore thermal fatigue behavior of alumina ceramics can be represented by derived equation. Also theoretical single cycle critical thermal shock temperature difference can be calculated by this equation and the result was consistent with the experimental result well.

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Physics-based OLED Analog Behavior Modeling

  • Lee, Sang-Gun;Hattori, Reiji
    • Journal of Information Display
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    • v.10 no.3
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    • pp.101-106
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    • 2009
  • In this study, a physical OLED analog behavior model for SPICE simulation was described using the Verilog-A language. The model was presented through theoretical equations for the J-V characteristics of OLED derived according to the internalcarrier emission equation based on a diffusion model at the Schottky barrier contact, and the mobility equation based on the Pool-Frenkel model. The accuracy of this model was examined by comparing it with the results of the device simulation that was conducted.

Theoretical Modeling of the Resonant Column Testing with the Viscosity of a Specimen Considered (점성을 고려한 공진주 실험의 이론적 모델링)

  • 조성호;황선근;권병성;강태호
    • Journal of the Korean Geotechnical Society
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    • v.19 no.4
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    • pp.145-153
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    • 2003
  • The resonant column testing determines the shear modulus and material damping factor dependent on the shear strain magnitude, based on the wave-propagation theory. The determination of the dynamic soil properties requires the theoretical formulation of the dynamic behavior of the resonant column testing system. One of the theoretical formulations is the use of the wave equation for the soil specimen in the resonant column testing device. Wood, Richart and Hall derived the wave equation by assuming the linear elastic soil, and didn't take the material damping into consideration. Hardin incorporated the viscoelastic damping of soil in the wave equation, but he had to assume the material damping factor for the determination of the shear modulus. For the better theoretical formulation of the resonant column testing, this study derived a new wave equation to include the viscosity of soil, and proposed an approach for the solution. Also, in this study, the equation of motion for the testing system, which is another approach of the theoretical formulation of the resonant column testing, was also derived. The equation of motion leads to the better understanding of the resonant column testing, which includes the dynamic magnification factor and the phase angle of the response. For the verification of the proposed equation of motion for the resonant column testing, the finite element analysis was performed for the resonant column testing. The comparison of the dynamic magnification factors and the phase angles far the system response were performed.