• Journal of Ocean Engineering and Technology
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• v.38 no.2
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• pp.53-63
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• 2024

Submerged breakwaters can be installed underneath floating structures to reduce the external wave loads acting on the structure. The objective of this study was to establish an optimization analysis framework to determine the corresponding shape and position of the submerged breakwater that can minimize or maximize the external forces acting on the floating structure. A two-dimensional frequency-domain boundary element method (FD-BEM) based on the linear potential theory was developed to perform the hydrodynamic analysis. A metaheuristic algorithm, the advanced particle swarm optimization, was newly coupled to the FD-BEM to perform the optimization analysis. The optimization analysis process was performed by calling FD-BEM for each generation, performing a numerical analysis of the design variables of each particle, and updating the design variables using the collected results. The results of the optimization analysis showed that the height of the submerged breakwater has a significant effect on the surface piercing body and that there is a specific area and position with an optimal value. In this study, the optimal values of the shape and position of a single submerged breakwater were determined and analyzed so that the external force acting on a surface piercing body was minimum or maximum.

• The Research Journal of the Costume Culture
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• v.16 no.2
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• pp.305-318
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• 2008

The purpose of this study was to analyze the appearance management behavior and ornament wearing practices in relation to the body satisfaction and body image. The questionnaire was administrated to 261 female college students in Chungbuk area. Most respondents were dissatisfied with their bodies, especially with weight and lower part of their body. Among three factors of body image, they showed a great concern about appearance of body itself than body shape management and physical attractiveness. Most female students attempted ear-piercing and hair dyeing as appearance management behavior. They preferred to wear earrings, necklaces and rings, in the order. There was a significant relationship between body satisfaction and body image. Also, there were significant relationships among body image, appearance management behavior, and ornament wearing practices.

• The Research Journal of the Costume Culture
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• v.12 no.5
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• pp.721-736
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• 2004

The aim of this study is to clarify aesthetic values and sociocultural meanings that reappears in contemporary fashion. In order to analyze aesthetic values and symbolic meanings of body decoration, I examined the concepts and expression methods of the body decoration. Also, analyzed external characteristics of expression and its internal meanings that applied in modern fashion. The expressions of body decoration represented in contemporary fashion are classified into direct and indirect methods. The direct method is expressed by tattoos, piercing, henna, make-up and body painting. And, indirect method is expressed by see-through look, body-conscious look and accessories that were utilized its patterns and the material adaptation methods. Such expression of body decoration in the modern fashion was represented into grotesque images and erotic images. The characteristics of grotesque images are abnormal state, hateful animal image and distorted or transformed body and the internal meanings are the pursuit of primitive, exoticism, the pursuit of playfulness, and resistance. The characteristics of erotic images are an exposure of body, see through, body-conscious and androgynous look and the internal meanings are the self-intoxication, naturalism and sexual pleasure.

• Journal of Welding and Joining
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• v.33 no.2
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• pp.78-84
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• 2015

Self-piercing rivet(SPR) is mechanical joining methods and which can be joining dissimilar materials. Unlike conventional riveting, SPR also needs no pre-drilled holes. During plastically deformation, SPR pierces upper sheet and joins it to under sheet. SPR has been mainly applied to the joining the automobile body and some materials, such as glass fiber reinforced polymer and aluminum alloy, which represent the sheet-formed materials for lightweight automobile. Glass fiber reinforced plastic(GFRP) has been considered as a partial application of the automobile body which is lighter than steels and stronger than aluminium alloys. It is needed SPR to join Al alloy sheets and GFRP ones. In this paper, in order to design the rivet and anvil, which are suitable for GFRP, the joinability was examined through simulations of SPR joining between GFRP and Al alloy sheets. For this study, AutoCAD was used for the modeling and the simulated using commercial FEM code DEFORM-2D. The simulated results for SPR process joining between GFRP and Al alloys were confirmed by the same conditions as experimental trials.

• Journal of the Society of Naval Architects of Korea
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• v.30 no.1
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• pp.104-114
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• 1993

In this paper, effects of free surface on viscous flow is investigated. Continuity equation coupled with Navier-Stokes equations are solved numerically by using an artificial compressibility method[1, 2]. The body-fitted generalized curvilinear coordinate system is employed to deal with arbitrary body shape. The IAF scheme with finite difference method is used to solve the equations, and a diagonal algorithm is applied to time-varying Jacobian matrices for the computational economics. Free surface shape is obtained by applying zero pressure condition to still water surface at each time step. A numerical test is made for larminar flow around a circular cylinder vertically piercing the free surface. Computed flow patterns are largely affected by the existance of free surface in low Reynolds number flows treated in this paper. Free surface causes viscous pressure drag to vary much in depth direction in accordance with the variations of flow pattern.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.9 no.3
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• pp.69-75
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• 2010

A hollow flanged spindle is generally used for the assembly of the driving shaft in some vehicles. This part has conventionally been manufactured by both hot forging and machining process, in which case a circular billet is hot-forged into a flanged spindle blank and then its central part is machined for hollow. Therefore, the development of a new forming technology without further machining processes has strongly been in demand. In this study, a new compound forging process of the hollow flanged spindle was proposed through the finite element simulation. By the proposed compound forging process, both extruding of the spindle body part and piercing for the hollow inside it can be performed at the same time. Metal flow patterns, forging defects and forging forces were investigated through the finite element simulation results.

• International Journal of Naval Architecture and Ocean Engineering
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• v.4 no.3
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• pp.281-290
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• 2012

Hydrodynamic analysis of a surface-piercing body with an open chamber was performed with incident regular waves and forced-heaving body motions. The floating body was simulated in the time domain using a 2D fully nonlinear numerical wave tank (NWT) technique based on potential theory. This paper focuses on the hydrodynamic behavior of the free surfaces inside the chamber for various input conditions, including a two-input system: both incident wave profiles and forced body velocities were implemented in order to calculate the maximum surface elevations for the respective inputs and evaluate their interactions. An appropriate equivalent linear or quadratic viscous damping coefficient, which was selected from experimental data, was employed on the free surface boundary inside the chamber to account for the viscous energy loss on the system. Then a comprehensive parametric study was performed to investigate the nonlinear behavior of the wave-body interaction.

• Journal of the Korean Society of Clothing and Textiles
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• v.27 no.8
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• pp.981-991
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• 2003

The purpose of this study is to observe the cultural phenomenon in modern society from the point of view of pastiche, analyze the characteristics of pastiche, create a framework for studying modem fashion and body ornamentation, one of the facts of cultural phenomenon and, based on these aspects, will observe the pastiche phase, which occurred in body ornamentation of modem fashion in the late 1990's Collections. The characteristics of pastiche is that it transcends meaning, alters the usage of objects, raises the beauty of alienation and pursues temporariness. Observing pastiche, according to its definition and characteristics, as it appears in body ornamentation of modem fashion, the results were as follows: First of all, in terms of transcending meaning, body ornamentation of modern fashion is a mixture of all past styles. Secondly, use of objects in body ornamentation of fashion has shown the use of things which have never been used in accessorizing before, such as birdcages, bones of body, castle. Third, in terms of the raising of the beauty of alienation, accessories from countries, which were not high interest groups in the past, such as piercing, scar, corpulent, are being used as high-fashion accessories in body ornamentation of modern fashion. Fourth, in terms of the pursuit of temporariness, external ornamentation in body ornamentation of modern fashion is seen as permanent changes to the outer body, such as tattoos, piercings, hair color and the more temporary changes, such as coloring.

• Journal of Fashion Business
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• v.16 no.6
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• pp.1-20
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• 2012

This study aims to define the influences of an individual's talent types and body consciousness factors on high((intense)-level appearance management behavior in 367 adults(female 172 and male 195). The present study is the first to consider both human talent type and the body consciousness on the high level-appearance management behavior correlates to appearance management behaviour. According to the result of the analysis, plastic surgery on body forms or faces are done by few people. However, straightening teeth, ear piercing, removal of spots or imperfections, and eyebrow tattoos are conducted by many consumers without much resistance. It is rather widely accepted, despite the fact that it can cause pain, discomfort, and side-effects. Furthermore, although excessive acts such as muscle training, dieting, weight managing, and oriental treatments can lead to side-effects, the standardized efficient beta value turned out to be high for these treatments. Thus, this study suggests that both the interpersonal talent among 8 talent factors and 2 body consciousness factors contributes to the reinforcement of the self-identity through high level-appearance management behaviors, but except risky plastic surgery. Therefore, this study supports the previous researches that body consciousness composed of self-source, which is desires and efforts to achieve the ideal body, and external-source, which is the internalization of other people's feedbacks.

• Transactions of the Korean Society of Mechanical Engineers
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• v.10 no.6
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• pp.876-888
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• 1986

The Study is concerned with the analysis of unconstrained axisymmetric piercing as a nonsteady forging process by the rigid-plastic finite element method. In the numerical analysis of axisymmetric piercing, the initial velocity field is generated by assuming the material as a linear viscous material to begin with in order to facilitate the input handling and to ensure better convergencey. The strain-hardening effect for nonsteady deformation and the friction of the die-material interial interface are considered in the formulation. Rigid body treatment is also incorporated in the developed program. The experiments are carried out for aluminum alloy specimens (A1204) with different specimen heights. It is shown that the experimental results are in excellent agreement with the finite element simulations is deformed configuration. For load prediction the theoretical prediction shows excellent agreement with th eexperimental laod in the initial stage of loading before fracture of the specimen is not initiated. Distribution of stresses, strains and strain rates has been found for the given cases in computation. On this basis several fracture criteria are introduced in order to check the fracture initiation. It is found that maximum shear criterion is capable of good fracture prediciton.