• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1993.12a
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• pp.63-69
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• 1993

In this paper the characteristics of Hydrostatic Bearing of piston of cylinder are investigated . The dynamic characteristic equations of piston considering both parallel and rotational motion and time dependent modified Reynolds Equation are analyzed and the dynamic pressure distribution of oil film is numerically calculated by perturbation method and finite difference method. and the atatic analysis is carried out. so, the influence of design parameter of piston on the characteristic of bearing is analyzed.

• The Korean Journal of Ecology
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• v.6 no.1
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• pp.1-13
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• 1983

A survey was conducted on the vegetation of southern slope of Daecheong-bong, Mt. Seolag, Located at the northern part of Taebaek mountain chain in the Central Korea. The altitudinal zonation of the vegetation was analyzed by distribution pattern of dominant species along thermal gradient, In additiion to these procedure th plant sociological studies by Braun-Blanquet(1964) were carried out. It was recognized that the vegetation is consist of 16 associations including Quercus mongolica-Lindera obtusiloba. association and the forest zone is classified into southern, central and northern part of cool temperate forest and subarctic forest.

• Communications of the Korean Mathematical Society
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• v.33 no.4
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• pp.1331-1339
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• 2018

In this paper the decomposition of basic equations of $(LCS)_n$-manifolds is carried out into horizontal and vertical projections. Further, we study the integrability of the distributions $D,D{\oplus}[{\xi}]$ and $D^{\perp}$ totally geodesic of semi-invariant submanifolds of $(LCS)_n$-manifold.

• Journal of Magnetics
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• v.2 no.3
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• pp.101-104
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• 1997

Vector Moving Preisach model has been applied to the unoriented Co-based alloy thin film media. In the model, the out-of plane easy axis distribution of the particles was derived directly from the texture coefficient phkl obtained from XRD analysis, which corresponds to the fraction of the grains that have the {hkl} plane lying parallel to in-plane direction. The model was validated, by its prediction of a variety of responses, including major loop, minor loop, and the angular dependence of coercivities.

• Proceedings of the Korean Geotechical Society Conference
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• 2003.06a
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• pp.119-127
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• 2003

For the calculation of internal stability, the hypothesis in conventional design is on the basis of two distinct zones, which are‘active zone’and‘passive zone’. This means that there is an abrupt discontinuous transition from active to passive states across a potential failure line. The existence of a discontinuity of this nature appears physically unreasonable, especially from kinematic considerations. A series of pull-out model tests was undertaken from a wall being rotated about the toe to find the strain distribution mobilized from near the wall face into the deep, stable zone through the centre plane. With this finding of transition zone, the objective of study is aiming at identifying the likely effect of this zone in designing method by comparing with the prevailing design method.

• Journal of applied mathematics & informatics
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• v.27 no.1_2
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• pp.301-313
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• 2009

This paper presents a Finite Element Method (FEM) application to thermal study of natural three layers of human dermal parts of varying properties. This paper carries out investigation of temperature distributions in these layers namely epidermis, dermis and under lying tissue layer. It is assumed that the outer skin is exposed to atmosphere and the loss of heat due to convection, radiation and evaporation of water have also been taken into account. The computations are carried out for one dimensional unsteady state case and the shape functions in dermal parts have been considered to be quadratic. A Finite Element scheme that uses the Crank-Nicolson method is used to solve the problem and the results computed have been exhibited graphically.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2004.05a
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• pp.385-388
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• 2004

The influence of material properties and process parameters on the strain distribution of stamping parts was studied by finite element method. For the parametric study, the investigation of variation of material properties was carried out with tensile test for a dozens of different steel sheets. The friction test for each surface and lubricants conditions are also carried out because the frictional characteristic is important parameter fur sheet metal forming. The geometry of stamping parts was measured by 3D scanner to build the tool model fer the FE analysis. As a result of analysis the major process parameter fer each automotive parts was investigated.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.9
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• pp.2396-2403
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• 1994

An experimental study on material characterization and mechanical properties of SMC(Sheet Molding Compounds) compression method parts was carried out. Simple compression test using grease oil as a lubricant was carried out to characterize flow stress of SMC at elevated temperatures. Two different mold temperatures, $130^{\circ}C{\;}and{\;}150^{\circ}C$ and two different mold speeds, 15, 45 mm/min were used for preparing the specimen of SMC compression molded parts. Surface roughness, tensile, and 3-point bending tests were used to determine the effects of molding temperatures and speeds on mechanical properties of compression molded SMC parts. Orientation and distribution of glass fiber in the compression molded SMC parts were also investigated by photographing the burnt flat specimen and taking SEM(Scanning Electron Microscope) of cross-sectional T-specimen.

• Structural Engineering and Mechanics
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• v.65 no.3
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• pp.275-290
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• 2018

The hygrothermal stresses in sandwich plate with composite faces due to through the thickness gradient temperature and (or) moisture content are investigated. The layer-wise theory is employed for formulation of the problem. The formulation is derived for sandwich plate with general layer stacking, subjected to uniform and non-uniform temperature and moisture content through the thickness of the plate. The governing equations are solved for free edge conditions and 3D stresses are investigated. The out of plane stresses are obtained by equilibrium equations of elasticity and by the constitutive law and the results for especial case are compared with the predictions of a 3D finite element solution in order to study the accuracy of results. The three-dimensional stresses especially the free edge effect on the distribution of the stresses is studied in various sandwich plates and the effect of uniform and non-uniform thermal and hygroscopic loading is investigated.

• Korean Journal of Veterinary Research
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• v.16 no.2
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• pp.115-119
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• 1976

The survey was carried out to investigate the average number of days from parturition to conception to 349 calving cases out of Holstein cows in total 154 heads observed. The results were as follows: 1. The average number of days from parturition to conception was $97.41{\pm}8.22$ and it's similar during the period from primipara to 4th calving order, and irregular during on and after 5th. 2. The average number of days from parturition to conception in calving month was observed all through the year: the prolongation among on April and July, and the brief duration among on January and March. 3. In the cases under 50 and 150 days after delivery, the distribution showed 53.56% and 83.91%, respectively, and it's about 20% between 70 and 90 days after delivery.