• Tribology and Lubricants
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• v.17 no.5
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• pp.373-379
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• 2001

The problem of interest is formulating elastic contact problem of a layered semi-infinite solid in terms of Fourier integral. The plane strain problem is considered for a solid composed of homogeneous isotropic two layers with different mechanical properties. General solutions for the subsurface stress and deformation field of frictionless elastic bodies under normal loading using of Fourier transformation technique are obtained. The numerical results for the stress distribution of coated solid for some particular cases are given.

• 한국방재학회:학술대회논문집
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• 2007.02a
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• pp.293-296
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• 2007

This study investigated the out-of-plane elastic buckling load and effective length factor of X-bracing system. The members of X-bracing system which are studied in this paper are rigidly attached to the structure at their end connections, and are pinned or rigidly connected at their point of intersection. The effective length factors are derived for the general case where the tension and compression brace have different material and geometrical properties.

• Communications of the Korean Mathematical Society
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• v.16 no.3
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• pp.399-404
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• 2001

We examine plane waves of the elastic reduced wave equation in the half-space, and show that linear combinations of them can cover all plane waves on the boundary. The proof is based on the complex analysis for the symbol in the (dual) variable in the normal direction to the boundary.

• Journal of the Korean Magnetics Society
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• v.5 no.5
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• pp.351-353
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• 1995

The physical origins of anomalous volume effect (Invar effect) and elastic effect (Elinvar effect) are critically examined. We found that, unlike the volume effect, the shear elastic properties are not much influenced by the ferromagnetic transition. This finding shows that the two anomalies originate from different physical origins, thus contradicting the conventional wisdom. We discuss the consequences of this finding in the light of recent experiments.

• Journal of Welding and Joining
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• v.34 no.5
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• pp.47-53
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• 2016

The aim of this study is to consider effect of weld elastic modulus on simulations of stress concentration and fatigue life for pressure vessel. The investigations include analysis with ADINA and WINLIFE softwares for whole body model about using condition of the boiler vessel. Values of weld elastic modulus were divided by 5 steps in butt weld area of the boiler vessel body. The stress concentration of the butt weld more was increased in case of higher elastic modulus of weld area because of higher difference of material properties between matrix and weld. It was concluded that the fatigue lives were decreased along increasing stress concentration due to high elastic modulus of weld. The matrix microstructure was estimated as pearlitic structure of ${\alpha}$ ferrite and pearlite. And the microstructures of welds along 5 steps of elastic modulus were estimated as bainitic fine pearlite and martensite as increasing elastic modulus.

• Coupled systems mechanics
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• v.5 no.3
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• pp.255-267
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• 2016

To investigate the surface effects on vibration of embedded circular curved nanosize beams, nonlocal elasticity model is used in combination with surface properties including surface elasticity, surface tension and surface density for modeling the nano scale effect. The governing equations are determined via the energy method. Analytically Navier method is utilized to solve the governing equations for simply supported at both ends. Solving these equations enables us to estimate the natural frequency for circular curved nanobeam including Winkler and Pasternak elastic foundations. The results determined are verified by comparing the results by available ones in literature. The effects of various parameters such as nonlocal parameter, surface properties, Winkler and Pasternak elastic foundations and opening angle of circular curved nanobeam on the natural frequency are successfully studied. The results reveal that the natural frequency of circular curved nanobeam is significantly influenced by these effects.

• Journal of the Korean Ceramic Society
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• v.35 no.4
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• pp.333-338
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• 1998

Mechanical properties of polycrystalline{{{{ {Ti }_{3 }{SiC}_{2 } }} were investigated. Hertzian indentation test using a spher-ical indenter was used to study elastic and plastic behavior in{{{{ {Ti }_{3 }{SiC}_{2 } }} A high ratio of hardness to elastic mo-dulus indicated that mechanical properties of{{{{ {Ti }_{3 }{SiC}_{2 } }} are somehow similar to those of metals. Indentation stress-strain curve deviated from an ideal elastic limit indicating exceptional plasticity in this material. De-formation zones were formed below the contact as well as around the contact area. Intragrain slip would ac-count for high plasticity.

• Earthquakes and Structures
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• v.2 no.3
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• pp.279-295
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• 2011

This paper develops a probabilistic methodology for the seismic reliability analysis of structures with random properties. The earthquake loading is assumed to be described in terms of response spectra. The proposed methodology takes advantage of the response spectra and thus does not require explicit dynamic analysis of the actual structure. Uncertainties in the structural properties (e.g. member cross-sections, modulus of elasticity, member strengths, mass and damping) as well as in the seismic load (due to uncertainty associated with the earthquake load specification) are considered. The structural reliability is estimated by determining the failure probability or the reliability index associated with a performance function that defines safe and unsafe domains. The structural failure is estimated using a performance function that evaluates whether the maximum displacement has been exceeded. Numerical illustrations of reliability analysis of elastic and elastic-plastic single-story frame structures are presented first. The extension of the proposed method to elastic multi-degree-of-freedom uncertain structures is also studied and a solved example is provided.

• The Journal of the Acoustical Society of Korea
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• v.20 no.4
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• pp.54-61
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• 2001

Magnetostrictive materials have nonlinear elasto-magnetic properties. However the constitutive equations to describe the nonlinear properties are not available, yet. In this study we develope the equation in magnetostrictive materials by use of piezomagnetic constitutive equation which is quasi-linearized. With the wave equation, we determine the propagation velocity inside the magnetostrictive materials when a plane wave propagates along a given magnetic field. Validity of the calculated velocity is verified through comparison with experimental velocity measurement results for the most representative magnetostrictive materials. Terfenol-D.

• Fashion & Textile Research Journal
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• v.5 no.1
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• pp.53-58
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• 2003

The stretch fabrics were made by the use of PTT[Poly(trimethylene terephthalate)] fibers and changes in their physical properties were analysed. Tenacity and elongation of D-1(PTT DTY) yarn were 3.32 g/d and 50.4%, respectively, while these of D-2(PTT+CDP DTY) yarn were 2.46 g/d and 32.1%, respectively. The tenacity of PTT-1 and PET-1 fabrics was similar, but the elongation of PTT-1 and PET-1 fabrics was 75% and 44%, respectively. Thus, the elongation of PTT-1 fabric was two times higher than those of PET-1 fabric. In addition, the elastic recovery at 20% elongation of PTT-1, PTT-2 and PET-1 fabric was 85.0%, 80.5% and 60.0%, respectively, indicating that so PTT-1 fabric showed better elastic recovery. The light, wash, and abrasion fastness of PTT-1 and PTT-2 fabrics were above Grade 3, Grade 4-5, and Grade 4-5, respectively. Therefore, there was little effect of substance on the fastness.