• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.42 no.7
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• pp.594-600
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• 2014

In modern warfare, securing communication channel by combatting opponents' electromagnetic attack is a crucial factor to win the war. Military satellite digital transponder is a communication payload of the next generation military satellite that maintains warfare networks operational in the presence of interfering signals by securely relaying signals between ground terminals. The transponder in this paper is classified as a partial processing transponder which performs cost effective secure relaying in satellite communication links. The control functions of transmission security achieve immunity to hostile interferences which may cause malicious effects on the link. In this paper, we present an efficient architecture for implementing the control mechanism. Two major ideas of pipelined processing in per-group control and software processing of blocked band information dramatically reduce the complexity of the hardware. A control code sequence showing its randomness with uniform distribution is exemplified and qualification test results are briefly presented.

• Journal of the Korean Society of Clothing and Textiles
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• v.28 no.5
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• pp.582-590
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• 2004

The purpose of this study was to evaluate thermal properties of Taekwondo wears with three different materials. As a begging step, the questionnaire survey about the actual condition of Taekwondo wears was conducted. With the results of the questionnaire, cotton/nylon(70/30) blended fabric(CN) that was newly woven with sweat absorbent finishing and cotton/spandex(95/5) blended fabric with flexibility property were developed. The same designed 3 Taekwondo wears with 3 different materials which were two different materials(CN and CS) and a current material(cotton/PET, CP) were made. Four young males volunteered for this study, they kicked and punched as Taekwondo action for 20 minutes. Mean skin temperature was the highest in CS(33.1${\pm}$0.8$^{\circ}C$) and the lowest in CP(32.7${\pm}$0.6$^{\circ}C$). Increasing degree of rectal temperature didn't show any significant difference. Clothing microclimate temperature on the thigh was higher in CS(32.8${\pm}$17.4$^{\circ}C$) than in CN(29.4${\pm}$1.1$^{\circ}C$) and CP(29.4${\pm}$1.0$^{\circ}C$). Clothing microclimate temperature on the back and humidity on the thigh didn't show any significant differences. Clothing microclimate humidity on the back was higher in CP(65${\pm}$20%RH) than in CS(61${\pm}$17％RH). Heart rate, total body weight loss, and local sweating were not significantly different by materials. Most subject responded more hot in CN than in others, but there were no significant differences at the subjective sensation of thermal humidity. They answered more comfortable in CN than in others. Tectile sensations were the best in CN and the worst in CS. From those results, first of all, it is necessary to be weighted on Taekwondo wears made of CN in the aspects of the dignity of military arts uniform. Secondly, CS was required to be lighted and enhanced for the subjective sensation. Third, CP weaved honey comb was asked more various design to eliminate sweat high competition power within the scope of the dignity of military arts uniform.

• Composites Research
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• v.28 no.4
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• pp.204-211
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• 2015

This paper presents a theory related to a two-dimensional linear cross-sectional analysis, recovery relationship and a one-dimensional nonlinear beam analysis for composite wing structure with initial twist. Using VABS including a related theory, the design process of the composite rotor blade has been described. Cross-sectional analysis was performed at cutting point including all the details of geometry and material. Stiffness matrix and mass matrix were linked to each section to make 1D beam model. The 3D strain distributions within the structure were recovered based on the global behavior of the 1D beam analysis and visualize numerical results.

• Journal of the Korean Society of Costume
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• v.56 no.1 s.100
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• pp.44-55
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• 2006

The purpose of this study is to examine the characteristics of man's boots in the Joseon Dynasty and compared them with those of the Ming and Qing Dynasty to find the influential relationships between them. Boots in the Joseon Dynasty are divided into several kinds such as Heukgwejapihwa, Hheuksapihwa(黑斜皮靴), Heukpihwa(黑皮靴), Mokhwa(木靴), Hyeopgeumhwa(挾金靴), Suhwaja (水靴子), Jeonpihwa, Gijahwa(起子靴), and Baekhwa(白靴). In addition, Jeong(精: footwear) was put inside boots. They tend to be named according to their materials or ornaments on them. First, Jeong put inside the boots is regarded as footwear for the comfort of the feet or protection against cold. Mokhwa appears in literature around the 19th century. As shown by remains and paintings of those days, it is considered to have become the common name of boots as it underwent many changes. On the other hand, a book in the era of King Gojong includes pictures of Suhwaja. Compared to Hukpihwa in the same book. The topside seems to have been raised in order to make the wearer who put on a military uniform feel comfortable when walking, since the bottom piece is hard. Baekhwa is worn not only with funeral garments but also with Sibok(時服), one of official uniforms. Boots in the Joseon Dynasty had been made following the design of the Ming Dynasty since official uniforms were conferred upon King Gongmin in the late Koryo Dynasty. But turning the late Joseon Dynasty its detailed design changed little by little. The topside of the boots became more round, the entrance part became wider, height of the shoes became taller, and the bottom piece became parallel to the ground.

• International Journal of Human Ecology
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• v.13 no.1
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• pp.117-128
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• 2012

This study compares the net effect of wearing different shoulder/arm armor systems on garment impediment perception and wearer acceptability. Two independent variables in this study were armor systems and shoulder/ arm movements. There were four armor systems of control garment and arm armor systems A, B, and C as well as five types of arm/shoulder movements, (shoulder flexion, should extension, shoulder abduction, shoulder horizontal flexion, and shoulder horizontal extension). Ten male volunteers wearing size medium battle dress uniform (BDU) with recent relevant military experience participated in this study. The volunteers performed shoulder/arm movements (while wearing each armor treatments) and completed the garment impediment perception as well as wearer acceptability scales. The body areas of neck side, shoulder top, and armscye front showed the highest frequency of reported impediments. Resistance to movement and localized pressure were the most frequently mentioned types of impediment. The armor system B had the most areas of impediment, and was rated as more restrictive than the control garment and armor system A for each movement. For wearer acceptability, no significant differences were found between the control garment and armor system A for all eight items; this indicated that subjects did not perceive a difference between wearing the control garment and armor system A. There was a trend for wearer acceptability to decrease from wearing the control garment to armor systems A to C to B.

• Journal of Fashion Business
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• v.6 no.1
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• pp.116-127
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• 2002

The hip-hop fashion of the nineteens is just as important in hip-hop as in rapping, breaking, or graffitiwriting to young people. Hip-hop fashions major influences range from martial-arts moves, to street-gang uniforms and paraphernalia. Hip-hop fashion grew and evolved with the subculture. The identification with street-gang culture is important to hip-hop in general and still set the pace for hip-hop fashion. There are things that are necessary fashion components for each segment of hip-hop life. So even prisons are now selling prison clothes. Explaining the look, The rawest street element is a jail element, so the strongest statement is a uniform with shirts and trousers that match perfectly, like a jail piece. Insiders can detect the away of gang and prison culture on the iconography of seemingly innocuous brands. Hip-hop glam is part of an evolution of hip-hop style. Rap's gone luxe, and it is women who are leading the high-fashion charge. They wear in diamonds and fur. Now it is a very glam. Now, many brands are upping their marketing activities through a focus on their women's lines in advertising, and featuring hot celebrities. There is also a lot of rethinking of looks going on. Sexy and tight is emerging as the style of choice in this market and fabrications are becoming more important, as designers refine and upgrade their women's line. The clothes of hip-hop glam were the ordinary with the extraordinary: Designer fur and leather with athletic team jerseys, Nike sneakers, diamond bracelets and mall brands like Guess and Fubu. The hip-hop musician's sporty hip-hop looks has amply young people. The hip-hop looks of baggy jeans, oversized shirts and rugged outerwear have become a part of mainstream fashion. Hip-hop fashion has the characteristics of being sporty. In the 90s, Military look has got one of the fashionable hip-hop fashion style. It does not have inner symbolic meaning or ideology but it only represents a fashion trend and revival fashion. Not only fashion designer but also hip-hop musician selected the trend for hip-hop fashion style.

• Journal of the Korean Society of Costume
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• v.55 no.2 s.92
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• pp.92-104
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• 2005

This study aimed to reveal the concept and background of emergence of black leather jacket that began appearing in full-scale among youth sub-culture from 1950's, and to research its styles and aesthetic features on the basis of that. The researcher has intended to a theoretical frame to recreate black leather jacket which has been developing in youth sub-culture style as a resource of new design in modern fashion trend through this study There are 5 styles of black leather jacket in youth sub-culture after 1950's. Firstly, biker style black leather jacket showed ruined war heroes substituting for military uniform. Secondly, rocker style black leather jacket brought the conversion in definition of masculinity. Thirdly, greaser style black leather jacket showed the beauty of uncleanness expressing resistance and violence with tattered dirty materials and excessive metal ornaments. Fourthly, headbanger style black leather jacket was prominent in various and compound decoration due to combination of rocker and hippie features. fifthly, punk style black leather jacket was influenced greatly by Sex Pistols. There are broadly three ecstatic features oi black leather jacket among youth sub-culture. With regard to displaying terrorism, black leather jacket displayed threatening aspects with black color, formative beauty of inverted triangle, additional decoration, and animal & brutal feelings. Paradoxical trophyism showed Nihilism, disorder, and resistance through black color that symbolize bad luck and unstability, trophyism with bad flavor, tattered material effect, and destructive message painting. Masculine eroticism appeared in accordance with pursuing after pleasure and masculine sexuality through exposure of buttocks and focused penis due to jacket's short length, and fetish of black.

• Geomechanics and Engineering
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• v.3 no.4
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• pp.291-321
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• 2011

The paper describes a simple numerical FLAC model that was developed to simulate the dynamic response of two instrumented reduced-scale model reinforced soil walls constructed on a 1-g shaking table. The models were 1 m high by 1.4 m wide by 2.4 m long and were constructed with a uniform size sand backfill, a polymeric geogrid reinforcement material with appropriately scaled stiffness, and a structural full-height rigid panel facing. The wall toe was constructed to simulate a perfectly hinged toe (i.e. toe allowed to rotate only) in one model and an idealized sliding toe (i.e. toe allowed to rotate and slide horizontally) in the other. Physical and numerical models were subjected to the same stepped amplitude sinusoidal base acceleration record. The material properties of the component materials (e.g. backfill and reinforcement) were determined from independent laboratory testing (reinforcement) and by back-fitting results of a numerical FLAC model for direct shear box testing to the corresponding physical test results. A simple elastic-plastic model with Mohr-Coulomb failure criterion for the sand was judged to give satisfactory agreement with measured wall results. The numerical results are also compared to closed-form solutions for reinforcement loads. In most cases predicted and closed-form solutions fall within the accuracy of measured loads based on ${\pm}1$ standard deviation applied to physical measurements. The paper summarizes important lessons learned and implications to the seismic design and performance of geosynthetic reinforced soil walls.

• Journal of Positioning, Navigation, and Timing
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• v.7 no.1
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• pp.37-42
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• 2018

This paper proposed a microstrip antenna that can perform jamming of satellite signals from the GPS L5, GLONASS G3, BDS B2 frequency bands (1164 - 1217 MHz) that are employed mainly for military purposes among the GNSS frequencies using unmanned aircrafts over the enemy's sky in time of emergency. The single element in the proposed antenna can be easily mounted to unmanned aircrafts. This study analyzed the characteristics of miniaturization and beam of radiating elements by applying the image theories and perturbation effect to satisfy the uniform level at ${\pm}45^{\circ}$ of beam steering goal due to the phase delay after antenna array. The designed microstrip antenna had a miniaturized radiating element area (x-y plane), which was reduced by 76.3% compared to that of basic microstrip antenna, and its beam width was $190^{\circ}$ in the E-plane and $140^{\circ}$ in the H plane. In addition, the simulation was conducted to determine the characteristics due to the phase delay by arranging the designed single microstrip antenna by $1{\times}4$ array and the results showed that beam steering of ${\pm}45^{\circ}$ is possible in the H-plane on the basis of $0^{\circ}$. Thus, the proposed antenna was verified to be effective in satellite signal jamming in the air as it was attached to the lower end of unmanned aircrafts.