• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2013.04a
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• pp.161-165
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• 2013

In this paper, possibility of controlling motion of a floating structure using a tuned liquid damper (TLD) is numerically investigated. A TLD is a tank partially filled with liquid. Sloshing phenomena of liquid inside a tank can suppress movement of the tank subject to external excitations at specific frequency. The effects of sloshing phenomena inside a rectangular floating body on its sway motion are investigated by varying excitation frequency. First, a grid-refinement study is carried out to ensure validity of grid independent numerical solutions using present numerical techniques. Then, sway motion of the floating body subjected to wave with five different frequencies are simulated. The normalized amplitudes of sway motion of the target floating body are compared over the frequency, for cases with and without water inside the floating body. It is shown that the motion of the floating body can be minimized by matching the sloshing natural frequency to excitation frequency.

• Steel and Composite Structures
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• v.24 no.1
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• pp.1-13
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• 2017

In order to improve the deformation capacity of the high-strength concrete shear wall, five high-strength concrete shear wall specimens confined with high-strength rectangular spiral reinforcement (HRSR) possessing different parameters, were designed in this paper. One specimen was only adopted high-strength rectangular spiral hoops in embedded columns, the rest of the four specimens were used high-strength rectangular spiral hoops in embedded columns, and high-strength spiral horizontal distribution reinforcement were used in the wall body. Pseudo-static test were carried out on high-strength concrete shear wall specimens confined with HRSR, to study the influence of the factors of longitudinal reinforcement ratio, hoop reinforcement form and the spiral stirrups outer the wall on the failure modes, failure mechanism, ductility, hysteresis characteristics, stiffness degradation and energy dissipation capacity of the shear wall. Results showed that using HRSR as hoops and transverse reinforcements could restrain concrete, slow load carrying capacity degeneration, improve the load carrying capacity and ductility of shear walls; under the vertical force, seismic performance of the RC shear wall with high axial compression ratio can be significantly improved through plastic hinge area or the whole body of the shear wall equipped with outer HRSR.

• The Research Journal of the Costume Culture
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• v.13 no.1
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• pp.6-17
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• 2005

The purpose of this research is to define low body shapes of Plus-sized women at ages between 21 and 69 whose satisfied the Plus-sized judgment criteria took part in this study. This research also classifies different body types, and provides basic data for designing skirt's and slacks' prototypes according to each body type. Based on factor analysis of the measured data, seven key factors are grouped. And four different body types are classified based on the cluster analysis using factor marks. Type 1 refers to those who are tall in stature and balanced. This body type is characterized by trapezoid body shape when looked from the front, and slim the abdomen, bulge the belly and flat the buttocks when looked from the side. Type 2 refers to short and an obese body shapes, with trapezoid front and bulge abdomen and belly and flat the buttocks. Type 3 refers to those who are of medium height and long-legged body shapes, with rectangular front, protruding belly and buttocks. Type 4 refers to obese body shapes, with rectangular front, protruding abdomen and belly, flat the buttocks. 9 items are available to judge Plus-sized women's low body types and the hit ratio is 93.5%.

• 한국전산유체공학회:학술대회논문집
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• 2011.05a
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• pp.395-406
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• 2011

In this research a numerical simulation method is developed for moving body in free surface flows using fixed staggered rectangular grid system. The non-linear free surface near the body is defined by marker-density method. The body boundary is defined by line segment connecting the points where the body surface and grid line meet. Continuity equation and Navier-Stokes equations are used as governing equations and the equations are coupled with two-step projection method. The velocities and pressures of body boundary and free surface cells are calculated with simultaneous iterative method. To treat a body movement in a fixed grid system, the volume displaced by moving body is added to the divergence of the body boundary cell. For the verification of the present numerical method. vortex shedding period of advancing cylinder is calculated and the period is compared with existing experiment results. Moreover, added mass and damping coefficients of a vertically excited box are calculated and the computed results are compared with published experiment results. Impulsive pressure and water level variation due to sloshing phenomenon are simulated and the results are compared with published experiment results. Varying the plunger shape, the waves generated by plunging type wave maker are compared with the 2nd order Stokes wave theory The plunger shape generating the wave that shows the best agreement with the theory is represented.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1999.06a
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• pp.20-29
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• 1999

The stress field in the body by tangential loading of a rectangular patch on a semi-infinite solid has been solved analytically using Boussinesque's potential function. Its validity was proved by saint-venant's principle in remote region of the and in the vicinity of the surface with superposition of point loads.

• Journal of the Korean Society of Costume
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• v.63 no.4
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• pp.84-100
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• 2013

Ancient Greece was a patriarchal society that distinguished gender roles between men and women. Although their costumes were composed of simple rectangular fabric without any technical complications in itself, the Greeks did try to express gender differences in their clothing. The final look of the Greek costume was dependent on the way the cloth draped onto its wearer as well as the wearer's identity. Greeks costume could just be seen as a rectangular fabric when it was not draped on a person's body. The purpose of this study is to examine how the gender differences were expressed in the ancient Greek drapery costume, which was made by using a completely different technical process, compared with the modern tailored costume. There are four elements of the costume that give the costume its formative shape, which are the wearer's body, the rectangular fabric (material as the first formative costume), the way the fabric is draped, and the final appearance as the second formative costume (the relationship between the wearer's body and the costume) and this study analyzes these elements individually. It is intended to analyze the gender characteristics and how each element appears in a different way from the perspective of Structuralism, an analytical method that considers a phenomenon as a total sum of the elements. Literature research was conducted and representative sculpture, painting and pottery, were used between the Archaic Period (B.C. 800~500) and the Classical Period (B.C. 500~323). The results show that the gender differences appear in each formative element of costume: First, the body was distinguished by the ancient Greek custom. The man's nudity was accepted while the woman's body was concealed. Second, in regards to the first formative costume, which was the rectangular fabric, men's were made with thick high quality wool because their involvement in outdoor activities meant that they needed clothes to stay warm, while the women wore clothes made of thin wool or hemp cloth, because their most of their activities were at home. Third, the way to drape the fabric shows the gender differences by changing the length of the clothing and its design ; men's short khiton was practical for big movement and at the same time the clothing exposed the man's body. The woman's doric khiton diversified its decoration by the size of the apotigma and by using the belt. Finally the second formative costume reflected the Greeks' social distinction between a man's body and a woman's body. The man's costume naturally exposed the man's body. On the other hand, the woman's long costume has a variety of shapes on the ground, that concealed her lower body, while the ornamental function was more accentuated than the man's costume. The gender differences expressed in Greek costume fundamentally reflected the point of view of the male and female body and their social roles in society.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.4 s.175
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• pp.1032-1038
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• 2000

The stress field in the body by tangential loading of a rectangular patch on a semi-infinite solid has been solved analytically using potential function. The validity of result of this study was proved by Saint-Venant's principle in the remote region and in the vicinity of the surface with superposition of point loads.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.23 no.7
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• pp.662-668
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• 2013

In this paper, possibility of controlling motion of a floating structure using a tuned liquid damper (TLD) is numerically investigated. A TLD is a tank partially filled with liquid. Sloshing motion of liquid inside a tank is known to suppress movement of the tank subject to external excitations at specific frequency. The effects of sloshing phenomena inside a rectangular floating body on its surge motion are investigated by varying external excitation frequency. First, a grid-refinement study is carried out to ensure validity of grid independent numerical solutions using present numerical techniques. Then, surge motion of the floating body subjected to external wave is simulated for five different excitation frequencies of which the center frequency equals to the natural frequency of internal liquid sloshing. The normalized amplitudes of surge motion of the target floating body are compared according to the excitation frequency, for the cases with and without water inside the floating body. It is shown that the motion of the floating body can be minimized by matching the sloshing natural frequency to the excitation frequency.

• Wind and Structures
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• v.11 no.5
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• pp.345-359
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• 2008

An experimental investigation of the flow over the rectangular body located in close proximity to a ground board was reported using the particle image velocimetry (PIV) technique. The present experiments were conducted in a closed-loop open surface water channel with the Reynolds number, $Re_H=1.2{\times}10^4$ based on the model height. In addition to the PIV measurements, flow visualization studies were also carried out. The PIV technique provided instantaneous and time-averaged velocity vectors map, vorticity contours, streamline topology and turbulent quantities at various locations in the near wake. In the vertical symmetry plane, the upperbody flow is separated from the sharp top leading edge of the model and formed a large reverse flow region on the upper surface of the model. The flow structure downstream of the model has asymmetric double vortices. In the horizontal symmetry plane, identical separated flow regions occur on both vertical side walls and a pair of primary recirculatory bubbles dominates the wake region.

• Wind and Structures
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• v.12 no.4
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• pp.299-312
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• 2009

It has long been studied about the flow around bluff bodies, but the effect of aspect ratio on the sharp-edged bodies in thick turbulent boundary layers is still argued. The author investigates the flow characteristics around a series of rectangular bodies ($40^d{\times}80^w{\times}80^h$, $80^d{\times}80^w{\times}80^h$ and $160^d{\times}80^w{\times}80^h$ in mm) placed in a deep turbulent boundary layer. The study is aiming to identify the extant Reynolds number independence of the rectangular bodies and furthermore understand the surface pressure distribution around the bodies such as the suction pressure in the leading edge, when the shape of bodies is changed, responsible for producing extreme suction pressures around the bluff bodies. The experiments are carried out at three different Reynolds numbers, based on the velocity U at the body height h, of 24,000, 46,000 and 67,000, and large enough that the mean boundary layer flow is effectively Reynolds number independent. The experiment includes wind tunnel work with the velocity and surface pressure measurements. The results show that the generation of the deep turbulent boundary layer in the wind tunnel and the surface pressure around the bodies were all independent of Reynolds number and the longitudinal length, but highly dependent of the transverse width.