• 대한조선학회논문집
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• 제55권3호
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• pp.252-264
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• 2018

The calculation of steady-state cavitating flows around Supercavitating Underwater Bodies (SUB's), which consist of a circular disk head (cavitator), a conical fore-body, a cylindrical middle-body and either a boat-tail or a flare-tail, are carried out. To calculate the axisymmetric cavitating flow, used is a commercial computational fluid dynamics code based on the finite volume method, Fluent. From the analysis of numerical results, the cavity and drag, affected by the fore-body and tail of the SUB's, are investigated. Firstly, the effect of the fore-body shape is investigated with the same disk cavitator and a cylindrical rear-body of fixed diameter. Then with the same cavitator and a fixed fore-body, the effect of the rear-body shape is investigated. Before the cavity generated by the cavitator covers the slant of fore-bodies sufficiently, the larger the cone angle of the fore-body(i.e., the shorter the slant length), the larger the drag and the slower the development of cavity. After the cavity covers the fore-body completely so that the pressure drag component of the body is vanished, the characteristics of drag-velocity curves are identical. Also, as the tail angle is bigger, the cavity generated by the cavitator is suppressed further and the drag becomes larger. The peak of the drag appears for the flare-tail, i.e., when the tail angle is positive(+). On the contrary, the trough of the drag appears for the boat-tail, i.e., when the tail angle is negative(-). When the tail angle is 5 degrees, the peak of the drag appears at the body speed of 80m/s and the value of the drag is 43% larger than that at the design speed of 100m/s. When the tail angle is -5 degrees, the trough of the total drag appears at 75m/s and that drag is 30% smaller than that of the cavitator, which means the rest of the body has a negative drag.

• 건축역사연구
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• 제20권1호
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• pp.77-93
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• 2011

Across the culture of Western Europe, dichotomy based on the visual sense has evolved. They believed eyes and ears requiring a distance related in recognition, are more developed than any other human senses in human body. Dominant position, as a condition to using a perspective, the eye has been just concentrated in the development of optical sight. But developed a variety of modern media, highlighting the importance of the other perception, it makes dichotomy to the expansion of perception over the single function of visuality. Recently, Guille Deleuze and Merleau-Ponty try to recover the sense of tactility segregated in skin from body keeping eyes for distance. By the result, the activity can be happened by being connected to the body rather than to eye in the space between the subject and object. From the phase of recognition where the human body tries to identify the object in the space considering a time, it will be changed for the subject to the phase of structure vice versa. Visual tactility is to eliminate the distance between subject and object. If the visual tactility is to erase the distance different from the visual in dichotomy, it will be occurred to having a tension and makes new relationship to work trying to move the subjective point of view in object. Like this evidence in analysis of architecture, it can be easy to find the Korean architecture rather than western architecture in terms of emphasizing the time and space. The fact, architecture of Lee Dynasty had been preserved and consisted basic form and style over the centuries makes us assume that visual tactility was considered as well as the visual sense. This study will be intensive in terms of visual and tactile inherent in the subject and how it is being connected to the movement in the space and time.

• Steel and Composite Structures
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• 제24권1호
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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 International Journal of Costume Culture
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• 제4권2호
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• pp.138-145
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• 2001

This study aims to compare the beauty of costume in the Gothic with that of Renaissance periods. By analyzing the beauty of costume which reflects the ideal of the age, this study attempts to provide the insight which can predict the beauty of future costume The characteristics of Gothic costume is the from of the loose enveloping of the body, which can be accounted for from the influence the Christian religion, and the emphasis on the vertical line influenced by the steeple in the Gothic architecture expressing the enthusiasm of the religion. The emphasis on height in the Gothic cathedrals was reflected in the hennin, pointed shoes, and lengthy sleeves of Gothic dress. The beauty of Gothic costume lies in the from of slender, the emphases on the vertical line, the we of heraldry and parti-color, and pointed hat and shoe. The Renaissance architecture shows a broad horizontal appearance. There is the similarity between the Renaissance costume and Renaissance architecture. The beauty of Renaissance costume lies in the form of the exposing body, the exaggerated silhouette, the emphasis on the horizontal line, the use of ruff and slash in order to display the beauty of human body and the beauty of cubic. The ideal beauty of Gothic and Renaissance costume was influenced by the spirit the age and was in contrast.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2006년 창립20주년기념 정기학술대회 및 국제워크샵
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• pp.403-406
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• 2006

A particle method recognized as one of gridless methods has been developed to investigate the nonlinear free-surface motions interacting to the structures. The method is more feasible and effective than convectional grid methods in order to solve the flow field with complicated boundary shapes. In the present study, breaking waves with a floating body are simulated to investigate fluid-structure interactions in the coastal zone.

• International Journal of Naval Architecture and Ocean Engineering
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• 제7권5호
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• pp.888-905
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• 2015

For Super-Cavitating Underwater Vehicles (SCUV), the numerical analyses and experiments in a large cavitation tunnel are carried out at relatively large Reynolds numbers. The numerical results agree well with experiments and the drag coefficient of SCUV is rarely changed by the Reynolds number. As the cavitation number is decreased, the cavity occurs and grows, the cavitator drag decreases and the body drag is affected by the degree of covering the body with the cavity. The tunnel effects, i.e. the blockage and the friction pressure drop of the tunnel, on the drag and the cavitation of SCUV are examined from the numerical results in between the tunnel and unbounded flows. In the tunnel, a minimum cavitation number exists and the drag of SCUV appears larger than that in unbounded flow. When the super-cavity covers the entire body, the friction drag almost disappears and the total drag of SCUV can be regarded as the pressure drag of cavitator.

• 한국실내디자인학회논문집
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• 제15권3호
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• pp.56-64
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• 2006

Human Being is being that have the reason as well as body, and first liaison consists through this body justly with outside. The essence of environmental problem such as today can speak that is a harmful traces for health that leave in air, water, soil that pass body. Actual nature is 'Ecological nature', that is necessary for human life directly in survival and offer the integrated relations with harmony. This grafting of principle, that is a construction for architecture and interior architecture in environment furtherance, is required. This is not a subject of usefulness and contemplation, but essential approach the cogredience, that is forming connection directly with nature, is required. Therefore, this research does Questel about 'Nature epistemology, which nature and human's relation can be integrated by alive practical relation. Through this, the Relatedness of 'Natural environment and construction surrounding' is accomplished 'the whole unity' and this research wish to investigate basis that a actual human work's environment can be completed as 'Ecological nature'.

• 한국해양공학회지
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• 제30권5호
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• pp.361-366
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• 2016

The aim of this study was to experimentally investigate the hydrodynamic performance of a hemispheric wave energy converter (WEC) and its wave power takeoff. The WEC is a heaving body-type point absorber with a hydraulic-pump power take-off (PTO) system. The hydraulic PTO system consists of a hydraulic cylinder, hydraulic motor, and generator, with consideration given to the hydraulic pressure and flow rate. Two body model shapes, including the original hemisphere and a bottom-chopped hemisphere, were considered. The heave RAOs of the two models were evaluated for various body drafts. The effects of the hydraulic PTO system on the RAOs were also investigated.

• 한국해양공학회지
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• 제33권1호
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• pp.26-32
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• 2019

The vortex flow behind a bluff body has been a subject of interest for a very long time because of its engineering applicability such as to vortex induced vibration. In the near wake of a bluff body, vortices are periodically shed in two shear layers, which originate in the trailing edges. The far wake is made up of the classical Karman vortices, which are connected together by streamwise and spanwise vortices. These vortex formations have been studied in many experimental and numerical ways. However, most of the studies considered non-cavitating flow. In this study, we investigated cavitating flow in the wake of a two-dimensional wedge. Experiments were conducted in a cavitation tunnel of Chungnam National University. Using a particle image velocimetry (PIV), we measured the velocity fields under two different flow conditions: non-cavitating and cavitating regimes. We also investigated the vortex shedding frequencies using an absolute pressure transducer mounted on the top of the test window. Throughout the experiments, it was found that the shedding frequency of the vortex was strongly affected by cavitation, and the Strouhal number could exceed its value in the non-cavitating regime.

• 대한건축학회논문집:계획계
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• 제35권3호
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• pp.31-40
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• 2019

The purpose of this study is to analyze the programs and the roles of Architectural Centers by their types in terms of the main body of organization. In order to figure out the programs and the roles, we examined the possibility to have different roles and varied collaboration ways depending on their main body types : central, municipal, architectural associations, and other private sectors. We also investigated the process of establishment of the Centers, their programs to promote the public and private partnerships focusing on the quality improvement of public architecture, research & investigations, education & publication, and cultural exchange & events. From this study, we could find out the differentiated management strategies and the ways of collaboration in public & private sectors for architectural centers and understand which aspects should be taken into consideration in the establishment of architectural centers. Centers initiated by public sectors generally have been focusing on supporting funds and centers initiated by private sectors relatively have developed the field oriented programs activating collaborative network and public participation.