• Title/Summary/Keyword: boundary stress

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Constraints of English Poetic Meter : Focused on lambic. (영어율격의 제약 - iambic을 중심으로 -)

  • Sohn Il-Gwon
    • Proceedings of the KSPS conference
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    • 2002.11a
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    • pp.64-69
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    • 2002
  • This study concerns the constraints of English Poetic Meter. In English poems, the metrical pattern doesn't always match the linguistic stress on the lines. These mismatches are found differently among the poets. For the lexical stress mismatched with the weak metrical position, $*W{\Rightarrow}{\;}Strength$ is established by the concept of the strong syllable. The peaks of monosyllabic words mismatched with the weak metrical position are divided according to which side of the boundary of a phonological domain they are adjacent to. Adjacency Constraint I is suggested for the mismatched peak which is adjacent to the left boundary of a phonological domain; *Peak] and Adjacency ConstraintII for the mismatched peak which are adjacent to the right boundary of a phonological domain. These constraints are various according to the poets(Pope, Milton and Shakespeare) : *[Peak [-stress], $W{\Rightarrow}{\;}*Strength$ and *Peak] in Pope; *[+stress][Peak [-stress] and *Peak] in Milton ; *[+stress][Peak [-stress], $W{\;}{\Rightarrow}{\;}*Strength$ and ACII in Shakespeare.

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An Analysis of the Wave Propagation of the flow-induced Elastic Stress Waves in the Layered Structure and it's 1 D.O.F. Modelling (적층구조물내의 유체유발 탄성응력파의 전파해석 및 1 자유도계 모델링)

  • Lee, J.K.;Lee, U.S.
    • Journal of the Korean Society for Precision Engineering
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    • v.12 no.11
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    • pp.132-139
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    • 1995
  • Turbulent boundary layer pressure fluctuation exerted on the surface of a structure can give rise to a elastic stress wave on the surface of the structure. The stress wave so called surface wave, will not only propagate along the surface of structure but also penerate into the structure. To reduce the transmission of stress wave into the structure the elastomer layer is usually attactched on the surface of structure. The transfer function, which is defined herein as the ratio of stress waves at the surface and bottom of the elastomer layer, is derved by use of the cylindrical coordinates system. The elastodynamics of the elastomer layer subjected to the turbulent boundary layer pressure fluctuation is represented by the simplified one degree-of-freedom model for easy prediction of the stress wave transmission as well as efficient design of the elastomer layer.

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Constraints of English Poetic Meter: Focused on Iambic (영시 율격의 제약 - Iambic을 중심으로 -)

  • 손일권
    • Korean Journal of English Language and Linguistics
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    • v.2 no.4
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    • pp.555-574
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    • 2002
  • This study concerns the constraints of English Poetic Meter. In English poems, the metrical pattern doesn't always match the linguistic stress on the lines. These mismatches are found differently among the poets. For the lexical stress mismatched with the weak metrical position, W⇒ Strength is established by the concept of the strong syllable. The peaks of monosyllabic words mismatched with the weak metrical position are divided according to which side of the boundary of a phonological domain they are adjacent to. Adjacency Constraint I is suggested for the mismatched peak which is adjacent to the left boundary of a phonological domain; /sup */Peak] and Adjacency ConstraintⅡ for the mismatched peak which is adjacent to the right boundary of a phonological domain. These constraints are various according to the poets (Pope, Milton and Shakespeare) : /sup */[Peak [-stress], /sup */W⇒ Strength and /sup */Peak] in Pope; /sup */[+stress][Peak[-stress] and /sup */Peak] in Milton; /sup */[ +stress][Peak[-stress], /sup */W⇒Strength and Adjacency ConstraintⅡ in Shakespeare.

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Bounary Element Analysis of Thermal Stress Intensity Factors for Cusp Cracks (커스프 균열에 대한 열응력세기 계수의 경계요소해석)

  • 이강용;조윤호
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.14 no.1
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    • pp.119-129
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    • 1990
  • In case that the body with a cusp crack is under uniform heat flow, thermal stress intensity factors are calculated by using boundary element method with linearized body force term. The crack surface is under insulated or fixed temperature condition and the types of crack are symmetric lip and airfoil cusps. Numerical values of thermal stress intensity factors for a Griffith crack and cusp cracks in infinite bodies are proved to be in good agreement within .+-.5% when compared with the previous numerical and exact solutions, respectively. The thermal stress intensity factors for symmetric lip and airfoil cusp cracks in finite bodies are calculated about various effective crack lengths, configuration parameters, and heat flow directions. With the same crack surface thermal boundary conditions, heat flow directions and crack lengths, there are no appreciable differences in variations of thermal stress intensity factors between symmetric lip and airfoil cusp cracks. The signs of thermal stress intensity factors for each cusp crack are changed with each crack surface thermal boundary condition.

Stress Fields for the V-notched Crack and Fracture Parameters by Boundary Collocation Method (V-노치균열의 응력장과 경계배치법에 의한 파괴변수)

  • Pae, Jung-Pae;Choi, Sung-Ryul
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.27 no.1
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    • pp.66-76
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    • 2003
  • The arbitrary V-notched crack problem is considered. The general expressions for the stress components on this problem are obtained as explicit series forms composed of independent unknown coefficients which are denoted by coefficients of eigenvector. For this results eigenvalue equation is performed first through introducing complex stress functions and applying the traction free boundary conditions. Next solving this equation, eigenvalues and corresponding eigenvectors are obtained respectively, and finally inserting these results into stress components, the general equations are obtained. These results are also shown to be applicable to the symmetric V-notched crack or straight crack. It can be shown that this solutions are composed of the linear combination of Mode I and Mode II solutions which are obtained from different characteristic equations, respectively. Through performing asymptotic analysis for stresses, the stress intensity factor is given as a closed form equipped with the unknown coefficients of eigenvector. In order to calculate the unknown coefficients. based on these general explicit equations, numerical programming using the overdetermined boundary collocation method which is algorithmed originally by Carpenter is also worked out. As this programming requires the input data, the commercial FE analysis for stresses is performed. From this study, for some V-notched problems, unknown coefficients can be calculated numerically and also fracture parameters are determined.

Effect of the boundary shape of weld specimen on the stress distribution (용접시편의 테두리 모양이 응력 분포에 미치는 영향)

  • Yang, Seung-Yong;Goo, Byeong-Choon
    • Proceedings of the KSME Conference
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    • 2004.11a
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    • pp.348-352
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    • 2004
  • In finite element analysis of mechanical behavior of weld, typical process is first to obtain a finite element model containing residual stress by conducting welding analysis and then to examine the computational specimen for various external loading. The numerical specimen with residual stress has irregular boundary lines since one usually begins the welding analysis from a body having regular straight boundary lines and large thermal contraction takes place during cooling of weld metal. We notice that these numerical weld specimens are different from the real weld specimens as the real specimens are usually cut from a bigger weld part and consequently have straight boundaries neglecting elastic relaxation associated with the cutting. In this paper, an iterative finite element method is described to obtain a weld specimen which is bounded by straight lines. The stress distributions of two types of weld specimen, one with regular and the other with irregular boundaries, are compared to check the effect of the boundary shape. Results show that the stress distribution can be different when large plastic deformation is induced by the application of external loading. In case of elastic small deformation, the difference turns out almost negligible.

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Boundary element analysis of singular thermal stresses in a unidirectional laminate

  • Lee, Sang Soon;Kim, Beom Shig
    • Structural Engineering and Mechanics
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    • v.5 no.6
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    • pp.705-713
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    • 1997
  • The residual thermal stresses at the interface corner between the elastic fiber and the viscoelastic matrix of a two-dimensional unidirectional laminate due to cooling from cure temperature down to room temperature were studied. The matrix material was assumed to be thermorheologically simple. The time-domain boundary element method was employed to investigate the nature of stresses on the interface. Numerical results show that very large stress gradients are present at the interface corner and this stress singularity might lead to local yielding or fiber-matrix debonding.

Theoretical formulations of current and unique Rayleigh waves with impedance boundary condition embedding normal stress

  • Nguyen, Xuan Quynh;Lee, Dongkyu
    • Smart Structures and Systems
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    • v.29 no.2
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    • pp.279-286
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    • 2022
  • In this article, a novel propagation formulation of Rayleigh waves in a compressible isotropic half-space with impedance boundary condition is proposed by embedding the normal stress. In a two-dimensional case, it is assumed that a design boundary is free of normal traction and a shear traction depends on linearly a normal component of displacements multiplied by frequencies. Therefore, impedance boundary conditions affect the normal stress, where the impedance parameters correspond to dimensions of stresses over velocity. On the other hand, vanished impedance values are traction-free boundary conditions. The main purpose of this article is to present theoretically the existence and uniqueness of a Rayleigh wave formulation relying on secular equation's mathematical analyses. Its velocity varies along with the impedance parameters. Moreover, numerical experiments with different values for the velocity of Rayleigh waves are carried out. The present Rayleigh waves study is a fundamental step in analyzing the cause and effect of physical states such as building or structure damages resulting from natural dynamics. The results of the study generate a basic design formulation theory to test the effects of Rayleigh waves affecting structures when an earthquake occurs. The presence and uniqueness of the proposed formulation is verified by mutual comparisons of several numerical examples.

Measurement of Wall Shear Stress Using Preston Tubes (프레스톤 튜브를 이용한 벽면전단응력 측정에 관한 실험적 연구)

  • 강신형;윤민수;전우평
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.18 no.7
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    • pp.1873-1880
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    • 1994
  • Fully developed turbulent flow in a circular pipe and laminar boundary layer on a flat plate were measured to develop a measuring technique of the wall sheat stress using Preston tubes. New empirical formulas to extimate displacement factor of Preston tube obtained through the present study. The displacement factor for turbulent flow was considerably different from that for the laminar flow. Measured wall shear stress was not pretty dependent on the displacement factor for Preston tubes in the inertia sublayer of turbulent boundary layer, however was considerably affected in the laminar boundary layer. Measuring error of skin friction using the CPM technique was 3% for turbulent and 5% for thin laminar boundary layers.

A study of stress intensity factors at the crack tips in a finite plate (평판내의 직선 crack tip에서의 응력확대계수에 관한 연구)

  • 조선휘;조희복
    • Journal of the korean Society of Automotive Engineers
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    • v.4 no.1
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    • pp.31-39
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    • 1982
  • In this paper, the stress intensity factors at the crack tips in a finite plate having a straight crack with arbitrary lengths and directions are analyzed by means of Boundary Collocation Method in Cartesian coordinates under the following two cases. A) Case of only considering stress components at the boundary collocation points B) Case of considering stress resultant at the boundary, in addition to case of )A) and analyzed by means of F.E.M. To certify the Boundary Collocation Method the solutions of B.C.M. are compared with the solutions of F.E.M. demonstrates the simplicity of input data preparation and the reduction of cpu time against F.E.M.

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