• Korean Institute of Interior Design Journal
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• v.17 no.3
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• pp.123-130
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• 2008

This study is about the Characteristic of glass outer skin expressions in space designs of contemporary society, due to the rapid development of information and digital technology. These days, the glass outer skin show the various images and space expressions which symbolize the informations and the society. The contemporary space designers focus on the glass as the structure materials, and purposely use the glass to achieve the structure concept which satisfies the needs of contemporary society. Therefore, it is a valuable work to analyze the meaning of glass, which has been used for the structure. Throughout the work which has been experienced by glass outer skin, theoretical studies have been achieved and recently the 14 examples were chosen as the glass structures based on the experimental research and frequency featured in magazines after year 2000, which we have analyzed in detail. Glass outer skin reflect the phrases of time in modern society, and throughout the meaning of it, we could see that the glass outer skin serve the roles in informations, interface, imaginary modernization, and as a landmark position. Therefore, in this study, we can make a definition of glass outer skin expression based on the situations of modem times by analyzing the symbolic meaning of glass outer skin in contemporary space designs.

• Journal of Biosystems Engineering
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• v.22 no.3
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• pp.289-294
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• 1997

The chestnut is a well-known and important forest product in Korea. The annual production of chestnut is about 100, 000tons and its cultivating area is 80, 000ha. However, the peeling process of outer and inner skins of chestnut is very difficult due to hardness and adhesiveness of chestnut skin. The peeling process of chestnut was operated by manual work and the performance of chestnut peeling machine is very low. The purpose of this study is to develope the prototype of new chestnut peeling system. The hardness of chestnuts was tested with six different drying conditions and its range was from 949$g/mm^2$ to 2, 149$g/mm^2$. The hardness of chestnuts was decresed gradually during the drying process. The chestnut peeling Process includes sorting, storage, drying, outer skin cutting, flame peeling, continuous frictional skin peeling, and inner skin cutting operation. The developed chestnut peeling system consists of outer skin cutter, flame peeler, continuous frictional skin peeler and inner skin cutter. The system can peel domestic chestnuts at 150$kg/hr$ with peeling rate of 78%.

• Steel and Composite Structures
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• v.2 no.2
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• pp.129-146
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• 2002

This paper describes a series of compression tests carried out on concrete filled double skin tubes (CFDST). Both outer and inner tubes are cold-formed circular hollow sections (CHS). Six section sizes were chosen for the outer tubes with diameter-to-thickness ratio ranging from 19 to 57. Two section sizes are chosen for the inner tubes with diameter-to-thickness ratio of 17 and 33. The failure modes, strength, ductility and energy absorption of CFDST are compared with those of empty single skin tubes. Increased ductility and energy absorption have been observed for CFDST especially for those having slender outer tubes with larger diameter-to-thickness ratio. Predictions from several theoretical models are compared with the ultimate strength of CFDST stub columns obtained in the tests. The proposed formula was found to be in good agreement with the experimental data.

• Structural Engineering and Mechanics
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• v.77 no.6
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• pp.745-751
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• 2021

Concrete filled double skin tubular members (CFDST) consist of double concentric circular or square steel tubes with concrete filled between the two steel tubes. The CFDST members, having a hollow section inside the internal tube, are generally lighter than ordinary concrete filled steel tubular members (CFT) which have a solid cross-section. Therefore, when the CFDST members are applied to bridge piers, reduction of seismic action can be expected. The present study aims to investigate, experimentally, the behavior of CFDST stub columns with double concentric square steel tubes filled with concrete (SS-CFDST) when working under centric compression. Two test parameters, namely, inner-to-outer width ratio and outer square steel tube's width-to-thickness were selected and outer steel tube's width-to-thickness ratio ranging from 70 to 160 were considered. In the results, shear failure of the concrete fill and local buckling of the double skin tubes having largest inner-to-outer width ratio were observed. A method to predict axial loading capacity of SS-CFDST is also proposed. In addition, the load capacity in the axial direction of stub column test on SS-CFDST is compared with that of double circular CFDST. Finally, the biaxial stress behavior of both steel tubes under plane stress is discussed.

• Journal of Power System Engineering
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• v.17 no.6
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• pp.95-101
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• 2013

A stereo PIV measurements in a circulating water channel has been performed to investigate the skin friction reduction mechanism of the outer-layer vertical blades first devised by Hutchins. In a recent PIV measurement study, considerable skin friction reduction was achieved as much as 2.73%~7.95% by outer-layer vertical blades array. In the present study, the influence of vertical blades array upon the characteristics of the turbulent coherent structures was analyzed by proper orthogonal decomposition method. It is observed that the vortical structures are cut and deformed by blades array and also the turbulent intensity and the Reynolds stress were weakened by the blades. These phenomena strongly associate the skin-friction drag reduction mechanism in the turbulent boundary layer flow.

• Architectural research
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• v.23 no.1
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• pp.11-17
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• 2021

A concrete-filled circular steel tube beam was fabricated, and a bending test was performed to analyze its failure modes, displacement ductility, bending-shear strength, and load-central deflection relationship. For the bending test, the installation position of the shape memory alloy (SMA) inside and outside the double-skin steel tube was used, and the rebar installation position, the concrete strength, the mixing of fibers, and the inner-outer diameter ratio as the main parameters. The test results showed that the installation positions of the reinforcements inside and outside the double-skin steel tube and the inner-outer diameter ratio of the steel tube affected the ductility, maximum load, and failure mode. In general, the specimen made of general concrete with SMA installed outside and inside (OI) the double-skin steel tube showed the best results.

• Journal of the Korean Society of Visualization
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• v.9 no.1
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• pp.20-28
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• 2011

An experimental assessment has been made of the drag reducing efficiency of the outer-layer vertical blades, which were first devised by Hutchins. The drag reduction efficiency of the blades was reported to reach as much as 30%. However, the drag reduction efficiency was quantified only in terms of the reduction in the local skin-friction coefficient. In the present study, a series of drag force measurements in towing tank has been performed toward the assessments of the total drag reduction efficiency of the outer-layer vertical blades. A maximum 9.6% of reduction of total drag was achieved. The scale of blade geometry is found to be weakly correlated with outer variable of boundary layer. In addition, detailed flow field measurements have been performed using 2-D time resolved PIV with a view to enabling the identification of drag reduction mechanism.

• The Research Journal of the Costume Culture
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• v.16 no.3
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• pp.533-546
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• 2008

This study aims on observing the recognition and attitude of caring for outer appearance by deducing the factors of men caring for their outer appearance at current point where male position is being emphasized in the appearance related market and their interest for outer appearance care is increasing. As a result of conducting a survey, male appearance caring behavior was distinguished into fashion, skin and cosmetic, cosmetic surgery, physical image, and hair factors, and among them, physical image factor showed the highest average, which proves that men generally have positive attitude towards caring for their looks. Concerning skin and cosmetics, the results show that interest is high regardless of age and occupation, and the lower the age is, the higher average for fashion, cosmetic surgery, and hair factors, proving that young men have more interest for caring after their looks. However, there was difference in outer appearance caring behavior pursued or favored by each age bracket according to the higher average for physical image in the age bracket higher than 30. Also, each factor of outer appearance caring behavior turned out to have significant correlation to each other.

• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.1 s.149
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• pp.115-124
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• 2006

Natural dyes are environmentally and human compatible. But they are not various or not fast in color. The mixed dyeing have been attempted to solve these disadventages of natural dyes. The persimmon juice dyed fabrics have brown-color and good hygienic properities however low color fastness. The onion dyeing show similar brown-color and have good color fastness caused by querectin existed in onion outer skins. Mixed dyeing was carryied out on silk fabrics using persimmion juice and onion outer skin extract in this study. The mixing method were persimmon juice dyeing and then onion dyeing(P-O), onion dyeing and then persimmon juice dyeing(O-P) and dyeing in the mixture of persimmon juice and onion outer skin extract simultaneously(P+O). The mordants were none-mordent, gallic acid after-treatment and alum after-treatment. Several persimmon juice dyed fabrics were irradiated for 2 hours before onion dyeing(PU-O). The color values of dyed silk fabrics were as follows. The persimmon juice dyed silk fabric developed to yellow-red color after 2 hours of uv irradiation. Onion dyed fabrics show similar yellow-red color after dyeing without uv irradiation. The effect of alum after-treatment on color difference were highest in onion dyeing. The dyeabilities of both P-O and O-P were higher than persimmom juice dyeing and onion dyeing. The dyeabilities of P+O was lower than persimmom juice dyeing and onion dyeing. The value of color difference of alum-treated fabric was the highest. The color difference of P-O and O-P caused from 2 to 4 hours of uv-irradiation were lower than those of persimmon juice dyed fabrics. Onion skin extract could prevent the color-change of persimmon juice dyed fabrics in mixed dyeing. The color difference of PU-O was higher than the P-O.

• Steel and Composite Structures
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• v.8 no.4
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• pp.297-312
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• 2008

A concrete filled double skin tubular (called CFDST in abbreviation) member consists of two concentric circular steel tubes and filled concrete between them. Purpose of this study is to investigate their bending characteristics experimentally. The two test parameters of the tubes considered were an inner-to-outer diameter ratio and a thickness-diameter ratio. As a result, their observed failure modes were controlled by tensile cracking or local buckling of the outer tube. Discussion is focused on the confinement effect on the filled concrete due to the both tubes and also the influence of the inner-to-outer diameter ratios on their deformability and load carrying capacity.