• Journal of Conservation Science
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• v.38 no.1
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• pp.55-63
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• 2022

The Bigyeokjincheolloe (bomb shell), a scientific cultural heritage, has outstanding historical value for sustaining a gunpowder weapon of Joseon. In this study, the bomb shell was modeled through three-dimensional (3D) scanning centered on the external shape and 𝛾-ray radiography-based on the internal shape. In particular, to improve the contrast in the radiographic image, optimization and image processing were performed. After these processes, the thickness of the inner wall (2.5 cm on average) and the positions of the three mold chaplets were clearly revealed. For exhibition purposes, the 3D model of the bomb shell was output to a 3D printer and the output was rendered realistic by coloring. In addition, the internal functional elements, such as Mokgok, fuse, mud, gunpowder, and caltrops, were reproduced through handwork. The results will contribute to the study of digital heritages in two ways. First, the internal and external shapes of the bomb shell were modeled by fusing two different technologies, namely, 3D scanning and 𝛾-ray radiography. Second, the internal shape of the bomb shell was constructed from the original form data and the reproduction was utilized for museum exhibitions. The developed modeling approach will greatly expand the scope of museum exhibitions, from those centered on historical content to those centered on scientific content.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.4
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• pp.391-396
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• 2015

When the temperature of a flange in a refrigerator is reduced to the dew point, condensation is generated on the flange. Generally, hot lines, having a temperature of $35^{\circ}C$, are located near the flange to increase its surface temperature above the dew point. Hot lines are installed in close contact with the flange in order to increase the heat transfer from the hot lines to the flange surface. Through this work, the effects of the hot line shape and installation conditions, including a gap between the hot line and flange, and the function of a spacer in the inner case of the refrigerator were investigated. Additionally, an optimal shape of the inner case for easy assembling is proposed considering the contact between the hot line and flange.

• Elastomers and Composites
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• v.48 no.4
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• pp.300-305
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• 2013

Part shrinkage in injection molding is inevitable phenomenon. Thus, it is necessary not only study on the reducing part shrinkage but characterization of part shrinkage. In this study, part shrinkage in injection molded 2.5 dimensional annular shaped specimens has been studied using glass fiber reinforced PC. Annular shaped specimens were designed with various sizes of outer diameter and thickness. Injection temperature, packing time and packing pressure were selected for operational conditions. Profile variations of outer and inner diameters of molded specimens for various operational conditions were investigated. Sizes of outer and inner diameters of injection molded specimens were smaller than the sizes of mold. Part shrinkage decreased as outer diameter and thickness increased. Part shrinkage showed anisotropic behavior and it depended upon gate location. Subsequently, molded specimens were not circular but oval in shape, and showed the largest shrinkage in the direction of gate. It was realized that the mold design such as gate design is important to control the shape of molded products.

• Journal of the Korean Society for Precision Engineering
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• v.29 no.2
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• pp.178-184
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• 2012

This paper presents a transformable track mechanism for wall climbing robots. The proposed mechanism allows a wall climbing robot to go over obstacles by transforming the track shape, and also increases contact area between track and wall surface for safe attachment. The track mechanism is realized using a timing belt track with one driving actuator. The inner frame of the track consists of serially connected 5R-joints and 1P-joint, and all joints of the inner frame are passively operated by springs, so the mechanism does not require any actuators and complex control algorithms to change its shape. Static analysis is carried out to determine design parameters which enable $90^{\circ}$ wall-to-wall transition and driving over projected obstacles on wall surfaces. A Prototype is manufactured using the transformable track on which polymer magnets are installed for adhesion force. The size of the prototype is $628mm{\times}200mm{\times}150mm$ ($Length{\times}Width{\times}Height$) and weight is 4kgf. Experiments are performed to verify its climbing capability focusing on $90^{\circ}$ wall to wall transition and driving over projected obstacle.

• Journal of the Korean Institute of Gas
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• v.18 no.2
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• pp.69-72
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• 2014

If LNG is leaked from 9% Ni steel inner tank by damage, LNG is retained by outer concrete tank. Then large tensile stress can be caused at cylindrical bottom of outer tank by temperature difference between outer and inner surface of outer tank. Therefore, in order to reduce the tensile stress is caused by temperature difference, corner-protection is installed with insulation and 9% Ni steel as a second barrier. In this paper, using finite element method, structural analysis was performed for rectangular and circular shape of knuckle and based on the results, fatigue life of welds of corner protection was predicted. As a consequence of structural analysis, safety factor of circular knuckle shows 33% bigger than rectangular one shows, and circular knuckle has 25% bigger fatigue life time than rectangle has. These results can be applied to life time assessment and design optimization in the future.

• Korean Journal of Plant Taxonomy
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• v.34 no.4
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• pp.273-285
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• 2004

A comparative micromorphology of petal and sepal of 15 species of Lycopus was undertaken to assess their usefulness in species identification and to evaluate their significance in the taxonomy using scanning electron microscope and stereo microscope. Five types of trichome are found within the genus: unicellular cylindrical trichome, unicellular trichome with papillae, simple multicellular trichome, capitate glandular trichome, and peltate glandular trichome. The types, distribution, and density of the trichomes show considerable variation among the taxa. The distributional pattern of the unicellular cylindrical trichomes on inner side of corolla is differed among the investigated taxa, and can be classified into four patterns. The apex shape of sepal and the incised position of calyx are also various and be recognizedas four patterns. The shape of cell composing in both outer and inner sides of petal and sepal are shown variously. Finally, the taxonomic significance of micromorphology of the petal and sepal in identification and elucidation of the genus Lycopus, especially among the species is also briefly discussed.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.5
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• pp.601-608
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• 2019

In this study, the effect of hull appendages on the high-speed catamarans with reverse bow shapes is compared and analyzed by numerical analysis and circulating water tank model test. The reverse bow shape showed an improved wave shape by shifting the generation position of forward divergent wave to the stern direction and was effective in resistance and stable running posture (Kim et al., 2019). In the model test results of the running performance as the wave patterns and the change of the running posture due to the fin fitted with the inner side of the inverted bow and the interceptor, 1) Trim characteristics of the inverted bow 2) Improvement of superposition of inner wave by Fin 3) The trim control by the fin and the interceptor is considered to be effective in reducing the impact of the two hull connection decks (wetdeck).

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.58 no.1
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• pp.1-9
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• 2022

In this study, the selection action on the mesh in the net pot for whelk (Buccinum opisthoplectum) is experimentally considered, and the selectivity was compared by the SELECT model and the Nashimoto's method with the probability model according to the contact shape of the mesh and the whelk. The experiments of the mesh size selectivity was conducted for two mesh sizes: 70 mm (inner stretched size 65.4 mm) and 44 mm (inner stretched size 39.5 mm). Selectivity experiments were conducted three times in total for each mesh size used 264 whelks. In addition, Nashimoto's method analyzed the retention probability using probability model for whether the mesh passed or not based on the carapace width of the whelk. As a result of the selectivity analysis, the 50% selection carapace width for the mesh size of 70 mm was similar to 43.62 mm in the SELECT model and 42.64 mm in the Nashimoto's method. However, the 44 mm mesh with relatively small mesh size showed differences of 40.01 mm and 26.80 mm, respectively. As for the mesh size selectivity of whelk, it was found that the smaller the mesh size, the lower the selectivity. In addition, in the selectivity study on the mesh size of whelk, an evaluation method that closely considers the contact shape between the mesh and the target species is required.

• Journal of the Korean Society of Costume
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• v.28
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• pp.239-253
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• 1996

The purpose of this dissertation is to exam-ine the hippie look which is one of the most popular fashion trends in the early 90s, in re-lation to the hippie style in 60s and cultural restoration. in order to investigate the re-lationship this dissertation studies the trans-feral phenomenon of anti-fashion into mother fashion in the basis of social and clutural theories. hippie culture is the anti-culture which appeared in America in the late 60s, it tried to create a new culture by subverting the ruling class culture with their combative life style and peculiar appearance which are distinguished from mother culture. First of all to examine the inner symbolic meaning and outer shape of the hippie style I divided the characteristics of the hippies into ideology social value and attitude on sex. in the aspect of ideology the hippie show strong subjectivity while mother culture shows ob-jectivity. in social value the hippie has the resisting chaacteristics while mother culture has the conformative characteristics. In the aspect of sex the hippie tries to break the fixed idea of mother culture. Hippie culture as anti-culture is symbolically expressed in hippie style fashion which is dif-ferent from mother fashion in shape. There-fore the inner meaning and the outer shape of the hippie style shows strong characteristics of anti-fashion. Hippie style as anti-fashion has an effect on high fashion in the late 60s and the early 70s and on hippie look which is restored in 90s. however hippie-look in 90s is a mother-fashion in which all symbolic mean-ings of the hippie style are weakened and the only outer shape of hippie style is presented and suggested. It doesn't show any cultural backgrounds ideology social value and new attitude on sex of the hippies. The transferal phenomenon of anti-fashion into mother-fashion is summarized as follows. First in the process of tranference to highfashion in 60s and 70s and hippie-look in 90s the resistance of the hippie style is weakened and only suggested through the outer look. Second the hippie style which reappeared in the high fashion and mother fashion in 90s are layered look military uniform mode flower print grunge look romantic look peasant look ethnic look gypsy style handicraft ornaments working suit style handicraft ornaments working suit style and the use of the see-through cloth. Third the fact that the popular and high fashion were influenced by anti fashion in 60s proves filter-up theory in fashion adaption theory. As I examined before the ideology of the hippies are faded in high fashion in 60s-70s and hippie-look in 90s. The symbolic meaning of the hippie style is also weakened and only presented as a fashion trend.

• Journal of Internet Computing and Services
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• v.10 no.6
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• pp.99-111
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• 2009

The result of Image segmentation, an indispensable process in image processing, significantly affects the analysis of an image. Despite the significance of image segmentation, it produces some problems when the variation of pixel values is large, or the boundary between background and an object is not clear. Also, these problems occur frequently when many objects in an image are placed very close by. In this paper, when the shape of objects in an image is circular, we proposed an algorithm which segment an each object in an image using the geometric characteristic of circular shape. The proposed algorithm is composed of 4 steps. First is the boundary edge extraction of whole object. Second step is to find the candidate points for further segmentation using the boundary edge in the first step. Calculating the representative circles using the candidate points is the third step. Final step is to draw the line connecting the overlapped points produced by the several erosions and dilations of the representative circles. To verify the efficiency of the proposed algorithm, the algorithm is compared with the three well-known cell segmentation algorithms. Comparison is conducted by the number of segmented region and the correctness of the inner segment line. As the result, the proposed algorithm is better than the well-known algorithms in both the number of segmented region and the correctness of the inner segment line by 16.7% and 21.8%, respectively.