• Journal of the korean society of oceanography
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• v.37 no.3
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• pp.91-107
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• 2002

The wintertime upwind flow in the Yellow Sea has been investigated through a series of two-dimensional numerical experiments in an idealized basin. A total of 10 experiments have been carried out to examine the effects of wind forcing, bottom friction and the presence of oceanic currents sweeping the shelf of the East China Sea. A spatially uniform steady and periodic wind stresses are considered along with comparison of linear and quadratic formulations. The wind-driven flow in the absence of oceanic current has been computed using Proudman open boundary condition (POBC), while the wind-driven current in the presence of oceanic current has been computed using Flather’s radiation condition (FOBC). The oceanic currents to be prescribed at the open boundary have been simulated by specifying uniform sea level gradients across the Taiwan Strait and the eastern ECS shelf, Calculations show that, as seen in Lee et al. (2000), oceanic flow little penetrates into the Yellow Sea in the absence of wind forcing unless a unrealistically low rate of bottom frictional dissipation is assumed. Both steady and time-periodic wind stresses invoke the upwind flow along the central trough of the Yellow Sea, independently of the presence of the oceanic current. The presence of oceanic currents very marginally alters the north-south gradient of the sea surface elevation in the Yellow Sea. Changes in the intensity and direction of the wind-induced mean upwind flow are hardly noticeable in the Yellow Sea but are found to be significant near Cheju Island where the gradient is reduced and therewith contribution of Ekman transport increases. In case of steady wind forcing circulation patterns such as two gyres on the slope sides, a cyclonic gyre on the western slope and an anticyclonic gyre on the eastern slope persist and the upwind flow composes part of the cyclonic gyre in the Yellow Sea. While in case of the time-periodic wind stress the appearance and disappearance of the patterns are repeated according to the time variation of the wind stress and the upwind flow accordingly varies with phase delay, mostly intensifying near the time when the wind forcing is approximately near the middle of the decaying stage.

• Journal of The Korean Association For Science Education
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• v.19 no.1
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• pp.62-77
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• 1999

Idealization has an important role in the process of learning as well as in physics research. The purpose of this study was to survey students' and science teachers' recognition of the ideal conditions involved in the process of problem solving and of explaining the natural phenomena. The instrument for probing the understanding of the ideal conditions in the domains of force, electricity and heat was administered to general high and science high school students and science teachers. The framework of responses composed of three categories. The first category is "idealized conditions relevant to problem", the second "not relevant idealized conditions", which has more delicate subcategories of general/ irrelevant conditions, simple statement of formula/ law, repeating problems, uncorrect explaining/ describing conditions, and the last "no responses". The results of analysis showed that the majority of the subjects well understood the various ideal conditions, especially for science high school students. But some of them could not differentiate the ideal condition from the general conditions, or they simply repeat the problem situation or the formula. The understanding of idealization is different by the domains of physics. We discovered that the misconceptions about the ideal conditions in various physical phenomena and revealed some interconnection of researches in the fields of misconception and the ideal condition.

• Journal of the Korean Society of Clothing and Textiles
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• v.33 no.4
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• pp.511-518
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• 2009

Freed from its traditional confinement to the human body, postmodernism in fashion exposes the defectiveness of body and abstracts from the body under. Deformation of the body denotes the break away from the idealized and standardized body for mass productions. It tends to experiment with extreme exaggeration in form, refusing to subscribe to the traditional values that build on the balance and symmetry of the body. Bodily deformation carried out historical and cultural pastiche opposes the sartorial convention and symbolism which results in the discord between signifiant and $signifi{\acute{e}}$ of clothing. As a type of intimate architecture, fashion always mediates the dialogue between clothes and body, or fashion and figure. My study suggests a framework to analyze bodily deformation as pastiche, focusing on the relationship between clothes and the body. In order to inquire the deformation of the body in fashion, my study examines subjects of the fashion collections of the turn of the 21st century, using the method of literature research and content analysis.

• Journal of the Korean Home Economics Association
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• v.44 no.3 s.217
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• pp.51-59
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• 2006

The purpose of this study is to determine the relevant variables of parent-leadership that influence family strength based on the transformational leadership and transactional leadership proposed by Bernard M. Bass and to investigate the primary impact of leadership on the subordinate's job satisfaction and job involvement to his/her supervisor. Therefore, this study will provide implications for the family through a diagnosis of the effect by leadership. The results of this research are as follows : 1) How is the relationship of parent-leadership and family strength? A positive correlation was found between transformational leadership scores and family strength. A negative correlation was found between nontransactional leadership scores and family strength. 2) How had transformational leadership and transactional leadership affected on the family strength? Transformational leadership had the strongest effect on family strength. How had the 7 sub- factors of transformational/transactional leadership affected family strength? Idealized influence and contingent reward had strong effect on family strength but management by except had a negative effect on family strength.

• Journal of Environmental Science International
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• v.18 no.8
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• pp.911-918
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• 2009

Electromagnetic interference (EMI) is defined as the interaction phenomena of electromagnetic waves scattered from a large structure or complex terrain. In this study, the propagation of linear wave is modeled with ray theory, direct simulation Monte Carlo (DSMC), and some classical theories on flat plates. The wave physics of reflection, refraction, and diffraction are simulated for the investigation of front and back scattering of the one-dimensional plane wave from a tower with ray theory and DSMC, respectively. The effect of rotating disk idealized from the real wind-turbine blades is modeled with a simplified version of the classical electromagnetic theory as well as DSMC based on the ray theory.

• Journal of Mechanical Science and Technology
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• v.17 no.10
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• pp.1543-1551
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• 2003

The present study investigates turbulent flows subject to strong wall injection in a channel through a Direct Numerical Simulation technique. These flows are pertinent to internal flows inside the hybrid rocket motors. A simplified model problem where a regression process at the wall is idealized by the wall blowing has been studied to gain a better understanding of how the near-wall turbulent structures are modified. As the strength of wall blowing increases, the turbulence intensities and Reynolds shear stress increase rapidly and this is thought to result from the shear instability induced by the injected flows at the wall. Also, turbulent viscosity grows rapidly as the flow moves downstream. Thus, the effect of wall-blowing modifies the state of turbulence significantly and more sophisticated turbulence modeling would be required to predict this type of flows accurately.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2003.10a
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• pp.113-117
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• 2003

The reliability of machined fiber reinforced composites (FRC) in high strength applications and the safety in using these components are often critically dependent upon the quality of surface produced by machining since the surface layer may drastically affect the strength and chemical resistance of the material [1,2,3,4]. Current study will discuss the characterization of fiber pull-out in orthogonal cutting of a fiber-matrix composite materials. A sparsely distributed idealized model composite material, namely a glass reinforced polyester (GFRP) was used as workpiece. Analysis method employs a force sensor and the signals from the sensor are processed using AR time series model. The experimental correlation between the fiber pull-out and the AR coefficients is examined first and effects of fiber orientation, cutting parameters and tool geometry on the fiber pull-out are also discussed.

• Journal of Ocean Engineering and Technology
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• v.17 no.2
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• pp.1-7
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• 2003

A common feature in the three-dimensional numerical model experiments of coastal discharge with simplifed model and idealized external forcings is investigated. The velocity fields due to the buoyancy and flow flux, are spreaded radiately and the surface velocites are much greater than homegeneous discharges. The coastal dischargd due to the Coriolis force and flow flux are shaped a anticyclical gyre (clockwise) and determined the scale of the gyre in the coastal zone, respectively. The bottom topography restricts a outward extention of the coastal fronts and it accelerates a southward flow.

• Journal of Mechanical Science and Technology
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• v.18 no.4
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• pp.597-605
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• 2004

Turbulent temperature field in a channel subject to strong wall injection has been investigated via direct numerical simulation technique. These flows are pertinent to internal flows inside hybrid rocket motors. A simplified model problem where a regression process at the propellant surface is idealized by wall injection has been investigated to understand how the temperature field is modified. The effect of strong wall injection displaces thermal boundary layer away from the wall and this causes a sharp drop of friction temperature. Turbulent diffusivity and dissipation time scale for temperature field are found to show large variations in the streamwise direction under application of wall blowing. It is, thus, expected that more sophisticated turbulence models would be required to predict the disturbed temperature field accurately.

• Structural Engineering and Mechanics
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• v.2 no.1
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• pp.95-112
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• 1994

This paper describes the formulation and application of a dynamic model for a conventional rail track subjected to arbitary loading functions that simulate wheel/rail impact forces. The rail track is idealized as a periodic elastically coupled beam system resting on a Winkler foundation. Modal parameters of the track structure are first obtained from the natural vibration characteristics of the beam system, which is discretized into a periodic assembly of a specially-constructed track element and a single beam element characterized by their exact dynamic stiffness matrices. An equivalent frequency-dependent spring coefficient representing the resilient, flexural and inertial characteristics of the rail support components is introduced to reduce the degrees of freedom of the track element. The forced vibration equations of motion of the track subjected to a series of loading functions are then formulated by using beam bending theories and are reduced to second order ordinary differential equations through the use of mode summation with non-proportional modal damping. Numerical examples for the dynamic responses of a typical track are presented, and the solutions resulting from different rail/tie beam theories are compared.