• Tribology and Lubricants
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• v.28 no.6
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• pp.297-302
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• 2012

We conducted 3D elastic contact analysis of a sharkskin surface pattern for the characteristic assessment of biomimetic shark skin structure pattern for engineering applications. Rough sharkskin surfaces of similar size with real shark skin scales are generated numerically. Under the assumption of the contact of a plate on the generated sharkskin surface, contact performances such as contact pressure, real contact area, and surface separation are evaluated.

• The Korean Journal of Rheology
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• v.7 no.3
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• pp.173-180
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• 1995

LLDPE/LDPE 혼합물의 유변 물성과 필름가공특성 필름 물성 및 LLDPE의 extrudate 표면상태를 살펴보았다. LLDPE에 LDPE를 혼합함으로써 용융 강도가 크게 향상 되는 것을 볼수 있었으며 혼합비에 따라 필름의 기계적 물성이 변화하는 것을 볼수 있었다. 즉 최고의 물성을 나타내는 적절한 혼합비율이 존재하였다. 본논문에 사용된 LLDPE/LDPE 혼합물에 있어서는 LDPE의 함량이 15∼30wt%일 때 가장 우수한 기계적 물성을 얻을수 있 었다. LLDPE 필름의 표면 불량 문제를 보기위하여 capillary를 이용하여 LLDPE extrudate 의 표면 튀틀림(distortion)의 진행순서를 살펴본 결과, 전단 응력이 0.23MPa 일때 sharkskin이 발현함을 볼수 있었다.

• Conservation Science in Museum
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• v.1
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• pp.53-59
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• 1999

Residual fatty acid of the basic material[Backgol] for reinforcement used on the edges of the lacquer ware inlaid box of Chosŏn Dynasty was analyzed. The result showed that it contained considerable amount of cholesterol. So it was confirmed to be animal material. Gas chromatography showed that its fatty acid composition is similar to that of sharkskin. On the basis of this analysis results, the damaged area of the object was restored by using sharkskin as a material for reinforcement.

• Journal of the Korean Society of Costume
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• v.58 no.4
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• pp.35-46
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• 2008

The purpose of this study was to closely examine the history of glasses and their cases used in the middle and late of Joseon Dynasty and identify inherent quality of our traditional glasses cases through color analyses of glasses cases' material and shape. While theoretical examination was conducted based on the literatures of glasses and their cases that firstly appeared in around Japanese Invasion (Imjin war) of Korea in 1592, practical analyses were demonstrated on photos of glasses cases used in the middle and late of Joseon Dynasty collected from both museum pieces and the internet which were grouped into wood, fabric, paper, sharkskin, hawksbill and cow's horn in accordance with their materials. 623 color samples were abstracted from collected 159 glasses cases and quantity analyses on each material were performed respectively. Abstracted representative colors based on the result of color analyses were classified into the main materials and accessories' color scheme. The result of this study are as follow: firstly, both Yellow and Yellow Red were mostly used in main materials. In Fabric case's colors were widely used in embroidery and in animal matter material cases such as sharkskin, hawksbill and cow's horn, which can be used as itself or dyed, Green Yellow shown in high frequency. Secondly, accessories were analyzed into similarity coloration with main materials. From this finding, it turns out that our traditional cases have characteristic of similarity coloration between main materials and accessories. Red Purple and Purple Blue in high frequency in accessories used as an accent color. Finally, based on the analysis of hue and tone, while the middle and low value colors shown in very high frequency, the high-chroma colors hardly shown.

• Tribology and Lubricants
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• v.29 no.5
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• pp.304-309
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• 2013

Shark skin has functionalities such as self-cleaning and antifouling; it also exhibits excellent drag reduction owing to a hierarchical structure of microgrooves and nanometer-long chain mucus drag reduction interfaces around the shark body. In this study, the wettability of a shark skin surface and its replicas are evaluated. First, a shark skin template is taken from a real shark. Then, shark skin replicas are produced directly from a shark skin template, using a micromolding technique. The quantitative replication precision of the shark skin replicas is evaluated by comparing the geometry of the shark skin template to the replica using 2D surface profiles. Contact angles at the solid-air-water interfaces are evaluated for the shark skin template and its replicas under two conditions: with and without hydrophobic coating. The results show that the microriblets on shark skin improve the hydrophobic feature and play a critical role in self-cleaning.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2003.05a
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• pp.1-4
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• 2003

본 연구는 경편성물의 특성에 영향을 미치는 중요한 구조변수인 조직, 편환의 계폐여부, 가이드바의 상호 움직임 방향에 따른 소리특성과 생리적 반응 사이의 관계를 파악함으로써 총합적 감성소재 설계를 위한 기초 자료를 제공하고자 하였다. 직물소리발생장치를 이용하여 7가지의 경편성물에 대한 마찰음을 녹음한 후, 이를 마찰음이 유발하는 생리반응을 측정하여 slow alpha파, fast beta파, ECG R-R, RESP, HF/LF, SCL, PV등을 분석하였다. 조직에 따라서는 LPT, Loundness(Z), Roughness(Z)와 Fluctuation strength(Z) 가장 큰 Sharkskin에서 fast beta파, ECG R-R, RESP는 증가하였으며 slow alpha파, PV, HF/LF는 감소하였다. 편환의 개폐여부에서는 폐환보다는 개환에서 Loudness(Z), Sharpness(Z), Fluctuation strength(Z)가 증가하였으며 RESP는 증가하고 HF/LF는 감소하여 개환이 더 불쾌한 감성을 유발하였다. 가이드바의 상호 움직임 방향은 counter보다는 parallel에서 slow alpha의 변화량이 감소하고 fast beta의 변화량이 증가하여 counter보다는 parallel이 더 불쾌한 감성을 유발하는 것으로 보인다. 또한 편성물의 음향특성 중 ΔL, Δf 와 Roughness(Z), Fluctuation Strength(Z)가 생리반응을 예측하는 중요한 요인으로써 나타났다.

• Fibers and Polymers
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• v.6 no.1
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• pp.89-94
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• 2005

The purpose of this study is to offer acoustical database of warp knitted fabrics by investigating frictional sound properties and physiological responses according to structural parameters such as construction, lap form, and direction of mutual guide bar movement. Fabric sounds of seven warp knitted fabrics are recorded, and Zwicker's psychoacoustic param­eters - loudness(Z), sharpness(Z), roughness(Z), and fluctuation strength(Z) - are calculated. Also, physiological responses evoked by frictional sounds of warp knitted fabrics are measured such as electroencephalogram (EEG), the ratio of high fre­quency to low frequency (HF/LF), respiration rate (RESP), skin conductance level (SCL), and photoplethysmograph (PPG). In case of constructions, frictional sound of sharkskin having higher loudness(Z) and fluctuation strength(Z) increases RESP. By lap form, open lap has louder and larger fluctuating sound than closed lap, but there aren't significant difference of physi­ological responses between open lap and closed lap. In direction of mutual guide bar movement, parallel direction evokes bigger changes of beta wave than counter direction because of its loud, rough, and fluctuating sound. Fluctuation strength(Z) and roughness(Z) are defined as important factors for predicting physiological responses in construction and mutual guide bar movement, respectively.

• Journal of the East Asian Society of Dietary Life
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• v.19 no.4
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• pp.618-626
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• 2009

Dombaeki Pipyun is a well-known Korean ethnic food in Kyungpook providence. We produced a Dombaeki Pipyun mixed with shark skin, cartilage, and herbs. The herbal mixtures (HM: 0, 0.075, 0.15, and 0.225%) were made of equal amounts of clove, fennel, and bay leaf. The purpose of this study was to examine how HM influences the sensory and textural characteristics of the Dombaeki Pipyun. The results showed that as the concentration of HM increased, its strength, cutting energy, hardness, brittleness, and chewiness decreased and its elasticity and cohesiveness increased. The $L^*$ and $b^*$ values generally decreased the $a^*$ value tended to increase as the concentration of HM increased. Ammonia and the fish-like odor decreased when the HM concentration was increased to 0.15%. However, there were no statistical significant differences in astringent, bitter, salty, sour, and sweet tastes. However, the savory taste significantly increased at an HE concentration of 0.15%. In terms of the mouth feel, there was not significant changes in airy.

• Journal of the Korean Society of Clothing and Textiles
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• v.41 no.2
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• pp.224-241
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• 2017

This study considered the change process for Western style shoes in Korea during the time of modernization in the 1920s to 1930s. Western style shoes were one of the items imported by foreigners since the Joseon Dynasty and had a significant impact on Korean dress code. It influence started to spread in the 1900s; however, few high level people wore Western shoes until the 1920s. The trend started to spread through newspaper advertisements and news articles after the mid 1920s. Western shoes such as modern girl and modern boy in the 1930s then entered into Korean culture. Korea under Japanese colonial rule was reorganized on a war footing in the latter half of the 1930s and the main materials for western shoes (cow leather, horse leather and sheepskin) were mobilized as materials for war production; subsequently, new materials using rubber were introduced. The representative material is 'Marine Leather (水産皮革)' and Sharkskin 'Gyoheok (鮫革)' and Whaleskin 'Gyeongpi (鯨皮).' Form is like the material has changed over time. This study also observed the flow of westernized Korean modern shoes as well as analyzed the details of materials and shape of western shoes by period. This represent basic materials to understand the legacy of western shoes in the age; in addition, systemic summary is organized by each kind, shape and materials for each style of western shoes.