• Title/Summary/Keyword: euler equation

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Bank's Market Power and Firm Access to Capital Markets in Asia

  • Lee, Sunglyong;Seol, Youn
    • Management Science and Financial Engineering
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    • v.19 no.1
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    • pp.43-47
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    • 2013
  • We investigate the effect of bank's market power on financing constraints of non-financial firms in 11 Asian countries between 1995 and 2009. Using firm-level data we analyze financial constraints with the Euler equation derived from the dynamic investment model. We find that with a highly concentrated banking sector firms which have high market power are less financially constrained. These results are consistent with an information-based hypothesis that more market power increases bank's advantage to produce information on potential borrowers.

Free Vibrations of Generally Restrained Beams (일반적인 단부조건을 갖는 보의 자유진동)

  • 신성철;김봉규;안대순;김선기
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2003.05a
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    • pp.864-869
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    • 2003
  • The purpose of this paper is to investigate the free vibration characteristics of tapered beams with translational and rotational springs and point masses at the ends. The beam model is based on the classical Bernoulli-Euler beam theory which neglects the effects of rotatory inertia and shear deformation. The governing differential equation for the free vibrations of linearly tapered beams is solved numerically using the corresponding boundary conditions. Numerical results are compared with existing solutions by other methods for cases in which they are available. The lowest four natural frequencies are calculated over a range of non-dimensional system parameters.

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Exponential Stabilization of an Axially Translating Tensioned Beam by Boundary Control Together with a Passive Damper (길이방향으로 이동하고 장력을 가진 보의 경계제어를 통한 지수안정화)

  • 최지윤;홍금식
    • Journal of Institute of Control, Robotics and Systems
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    • v.9 no.1
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    • pp.1-9
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    • 2003
  • An active control of the lateral vibration of a translating tensioned Euler-Bemoulli beam is investigated. The dynamics of the translating tensioned beam is represented by a non-linear hyperbolic partial differential equation. A right boundary control law based upon the Lyapunov's second method is derived. The transverse motion of the translating tensioned beam is controlled by a time-varying external force besides a passive damping applied at the right boundary. Exponential stability of the closed loop system is proved. Simulation results demonstrate the effectiveness of the proposed controller.

A New Numerical Method for Solving Differential Equation by Quadratic Approximation (포물선 근사법에 의한 상태방정식의 새로운 수치해석적 접근법에 관한 연구)

  • Lee, Jong-Gi;Kwon, Yong-Jun;Choi, Byoung-Kon;Moon, Young-Hyun
    • Proceedings of the KIEE Conference
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    • 2003.07a
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    • pp.107-109
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    • 2003
  • 전력계통의 과도 안정도 해석의 접근방법에는 SI(Simultaneous Implicit)법과 PE(Partitioned Explicit)법 두 가지방법을 사용해오고 있다. SI법에는 Trapezoidal법 등이 있고, PE법에는 Runge-Kutta법, Euler법등이 사용되고 있다. SI법인 Trapezoidal법은 PE법의 Runge-Kutta법 또는 Euler법에 비해 시간간격을 크게 해서 계산속도를 줄일 수 있다는 장점이 있지만, 정화도면에서는 신뢰한 수 없는 단점이 있다. 이 논문에서는 포물선 사법을 이용하여 Trapezoidal법의 정확도를 개선학 수 있는 방법을 제시하고 명확한 수학적 증명을 통해 타당성을 보여준다. 연속함수와 불연속함수에 대해서 Runge-Kutta법과 Trapezoidal법과 제안한 방법을 적용시켜서 제안한 방법의 정화함을 보여준다.

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Turbulent Flow Calculations Using an Unstructured Hybrid Meshes (2차원 혼합격자를 이용한 난류유동 계산)

  • Kim J. S.;Oh W. S.;Kwon O. J.
    • 한국전산유체공학회:학술대회논문집
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    • 1999.05a
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    • pp.90-97
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    • 1999
  • An implicit turbulent flow solver is developed for 2-D unstructured hybrid meshes. Spatial discretization is accomplished by a cell-centered finite volume formulation using an upwind flux differencing. Time is advanced by an implicit backward Euler time stepping scheme. Flow turbulence effects are modeled by the Spalart-Allmaras one equation model, which is coupled with wall function. The numerical method is applied for flows on a flat plate, the NACA 0012 airfoil, and the Douglas 3 element airfoil. The results are compared with experimental data.

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Design Optimization of Transonic Airfoils Based on the Navier-Stokes Equation (Navier-Stokes 방정식을 이용한 천음속 익형의 설계최적화 연구)

  • Lee Hyeong Min;Jo Chang Yeol
    • 한국전산유체공학회:학술대회논문집
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    • 1999.05a
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    • pp.177-185
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    • 1999
  • The airfoil design optimization procedures based on the Navier-Stokes equations were developed, This procedure enables more realistic and practical transonic airfoil designs. The modified Hicks-Henne functions were used to generate the shape of airfoils. Five Hick-Henne functions were used to design upper surface of airfoil only. To enhance the ability of Hick-Henne function to generate various airfoil shape with limited number of functions, the positions of control points were adjusted through optimization procedure. The design procedure was applied to the single-point design for the drag minimization problem with lift and area constraints. The result shows the capability of the procedure to generate much realistic airfoils with very small drag-creep in the low transonic regime. This is mainly due to the viscosity effect of Navier-Stokes flow analysis. However, in the higher transonic range tile drag-creep appears. The multi-point design is shown to be an effective way to avoid the drag-creep and improve off-design performance which is very similar in the Euler design.

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Dynamic behavior of axially functionally graded simply supported beams

  • Selmi, Abdellatif
    • Smart Structures and Systems
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    • v.25 no.6
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    • pp.669-678
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    • 2020
  • This paper focuses on the free vibration analysis of axially functionally graded (FG) Euler-Bernoulli beams. The material properties of the beams are assumed to obey the linear law distribution. The complexities in solving differential equation of transverse vibration of composite beams which limit the analytical solution to some special cases are overcome using the Differential Transformation Method (DTM). Natural frequencies and corresponding normalized mode shapes are calculated. Validation targets are experimental data or finite element results. Different parameters such as reinforcement distribution, ratio of the reinforcement Young's modulus to the matrix Young's modulus and ratio of the reinforcement density to the matrix density are taken into investigation. The delivered results prove the capability and the robustness of the applied method. The studied parameters are demonstrated to be very crucial for the normalized natural frequencies and mode shapes.

Dynamic Instability of Elastically Restrained Valve-pipe System (탄성 지지된 밸브 배관계의 동적 불안정)

  • Son, In-Soo;Hur, Kwan-Do;Gal, Young-Min
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.9 no.5
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    • pp.90-95
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    • 2010
  • The dynamic instability and natural frequency of elastically restrained pipe conveying fluid with the attached mass are investigated in this paper. Based on the Euler-Bernoulli beam theory, the equation of motion is derived by using extended Hamilton's Principle. The influence of attached mass and its position on the dynamic instability of a elastically restrained pipe system is presented. Also, the critical flow velocity for the flutter and divergence due to the variation in the position and stiffness of supported spring is studied. Finally, the critical flow velocities and stability maps of the pipe conveying fluid with the attached mass are obtained by changing the parameters.

On Certain Novel Subclasses of Analytic and Univalent Functions

  • Irmak, Huseyin;Joshi, Santosh Bhaurao;Raina, Ravinder Krishen
    • Kyungpook Mathematical Journal
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    • v.46 no.4
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    • pp.543-552
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    • 2006
  • The purpose of the present paper is to introduce two novel subclasses $\mathcal{T}_{\mu}(n,{\lambda},{\alpha})$ and $\mathcal{H}_{\mu}(n,{\lambda},{\alpha};{\kappa})$ of analytic and univalent functions with negative coefficients, involving Ruscheweyh derivative operator. The various results investigated in this paper include coefficient estimates, distortion inequalities, radii of close-to-convexity, starlikenes, and convexity for the functions belonging to the class $\mathcal{T}_{\mu}(n,{\lambda},{\alpha})$. These results are then appropriately applied to derive similar geometrical properties for the other class $\mathcal{H}_{\mu}(n,{\lambda},{\alpha};{\kappa})$ of analytic and univalent functions. Relevant connections of these results with those in several earlier investigations are briefly indicated.

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Computer-Aided Steady state Analysis of Induction Motor (컴퓨터를 이용한 유도전동기의 정상상태 해석)

  • Jung, Yon-Tack;Seo, Young-Soo;Kim, Young-Chun;Cho, Moon-Taek;Lee, Sang-Bong
    • Proceedings of the KIEE Conference
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    • 1993.07b
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    • pp.683-685
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    • 1993
  • Semiconductor switches are modelled as binary inductors, as a very low value of inductance during conduction, and infinite value of inductance otherwise. The system matrix is partitioned in such a manner as to permit efficient handling of switch status. The backward Euler method of integration is used for the solution of equation to ensure convergence. The application of thristor switching to induction motor speed control has resulted in a number of unconventional supply systems. In this paper, an analytic method for predicting the steady-state of performance of system is presented.

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