• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.6
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• pp.94-99
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• 2012

Due to economic growth, the number of cars has grown rapidly and consequently traffic accidents have grown in direct ratio. This reminds us that braking device of a vehicle is an important factor to prevent traffic accidents. Aim these researches to speed and lighten the braking system of vehicles, to lengthen its durability and to shorten the stopping distance. However, it is still difficult to analyze quantitatively and clearly the reason and solution for abnormal wear of disc and pad or judder in flywheel mode. Therefore this study was carried out to presume for mutual relation of analysis condition to get the optimum temperature by two-way layout. The results shown that coefficient of determination has a fine reliability over 92.57% and temperature is made by two-way layout.

• Journal of the Korea Fashion and Costume Design Association
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• v.15 no.1
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• pp.31-45
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• 2013

Fashion appears as a similar sense of form in a regularly cyclical way. The part highlighted in the female body also becomes that way. The social and cultural problem of fashion is also a matter about the selection of a wearer on how to wear in what environment. Power dressing means an attire that makes you feel dignity, intelligence or power and an attire that is needed to succeed in the business society. It is based on the fact that women started wearing tailored suits that were regarded as the exclusive item of men as the women's social activity was actively progressing. The purpose of the study is to analyze the problem of styles in the social and cultural perspectives. The power dressing was repeatedly appeared in 1930s, 1980s and 2000s. Therefore, this study collected photo data and literature documents to analyze and compare shoulders represented during these three periods, and to examine what social cultural environment was operated for each period and how the designers of each period expressed with clothes. Power dressing is characterized by the use of shoulder pad for the first time for 1930s, the extended shoulder for 1980s and the design the extended shoulder with the more decorative method for 2000s. Power dressing has been utilized as women's gain and improvement of social status, flaunting of economical status and a symbol of individuality and identity.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2001.06a
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• pp.55-63
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• 2001

Friction and wear properties of brake friction materials containing different metal fibers (Al, Cu or Steel fibers) were investigated using a pad-on-disk type friction tester. Two different materials(gray iron and Al-MMC)) were used for disks rubbing against the friction materials. Results from ambient temperature tests revealed that the friction material containing Cu fibers sliding against cast iron disk showed a distinct negative ${\mu}$-ν (friction coefficient vs. sliding velocity) relation implying possible stick-slip generation at low speed. The negative ${\mu}$-ν relation was not observed when the Cu-containing friction materials were rubbed against the. Al-MMC counter surface. As applied loads increased, friction materials showed higher friction coefficients comparatively. Friction materials slid against cast iron disks exhibited higher friction coefficients than Al-MMC disks during high temperature tests. On the other hand, high temperature test results suggested that copper fibers in the friction material improved fade resistance and the steel fibers were not compatible with Al-MMC disks showing severe material transfer and erratic friction behavior during sliding at elevated temperatures.

• Journal of Wetlands Research
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• v.9 no.3
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• pp.35-42
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• 2007

The paved areas such as parking lots and roads are stormwater intensive landuses since they are impervious and have high pollutant mass emissions from vehicular activity. Vehicle emissions include different pollutants such as heavy metals, oil and grease, particulates from sources such as fuels, brake pad wear and tire wear. Especially, the released heavy metals can be easily absorbed on the surface area of small particulate materials because of its ionic strength. Therefore, by constructing the sedimental tank in structural BMPs as a pre-treatment facility, the particles and heavy metals both can be removed from the runoff at an instant. To understand the physico-chemical characteristics of sediments from sedimentation tank, one-year study at an infiltration trench and filtration system was conducted to quantify the metal mass absorbed on sediments with various particle sizes. The structural BMPs for this study are located in Yongin City, Kyunggido. The research results show that Cu, Zn and Pb are dominant metal compounds in the sediments. Also the metal concentrations are highest at the ranges of $425-850{\mu}m$ particle sizes. The results will provide the basic physico-chemical information of sediments to treat it as solid wastes and to determine the design criteria of sedimentation tank in structural BMPs.

• The Research Journal of the Costume Culture
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• v.6 no.3
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• pp.56-72
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• 1998

Vest is a general term for a sleeveless upper garment and it derives from a kolobus of a sleeveless tunic style that was started to be worn as a substitution of a chiton by the peasantry in Greek period. The kolobus started to be called a colobium or a tunica from Roman period and the former was named for a vest style tunica which was worn by the people of the lower classes in early Roman period. Similarly, a German colobium of North Europe which was worn during the same period was the same kind of clothe as the Roman colobium. The colobium came to be worn over a dalmatica as an outer garment by early Christians when it was the Middle Ages, who succeeded the tradition of colobium as they went through ancient Rome, Creek and Byzantine days. North Germans also succeeded the colobium tradition of ancient Germans as it was and so continued to wear it in tight style. The simple vest style of colobium was getting vanished from the mid of the Middle Agnes and a new style of vest named jupon was started to be worn by soldiers. The jupon was to protect soldiers' bodies from either were cold weather or enemies wearing under armors as it was made with double cotton pad by quilt. From 14th century, the jupon began to be worn by not only soldiers but also the humble of lower classes. All the jupon which were made in quilting and padding of that time began to be named a pourpoint by the humble. When Renaissance in 16th century came, the pourpoint began to be developed to an exaggerating body-line style. The neckline of pourpoint was getting highly influenced by Spain and a peacecod-belly of it emphasized the exaggerated masculine beauty of Renaissance by padding in round. The sleeves were puffed out and the whole purpoint was made to expose an inner chemise by slashing vertically or obliquely. But in 17th century, the pourpoint has been changed into more simple style without padding, puffing out and slashing influenced by the citizens' clothes of Netherlands. The pourpoint came to be more comfortable bulky style with short sleeves or sleeveless and straight side lines. The pourpoint in mid 17th century turned to be a bolero jacket style by gradually being tightened. It had been then changed into a vest style with sleeves and worn under an overcoat with the name of vest in the end of 17th century. The early vest was 2∼3 inches les in length than the overcoat and had long sleeves and many ornamental buttons on front. It was also made as a home wear to be worn it alone at home. In 18th century, the length of the vest became shorter compared with that of 17th century and the most important decorative item in clothes. It again came to have complete sleeveless vest style and had very short length reaching waist in the end of 18th century. When it was in 19th century, the vest had developed into more various style and colors and style had been applied to be worn by individuals with their tastes. Around the end of 19th century, the increasing tendency to be casual by industrialization influenced on clothes in all aspects of life and so the male vest has been gradually changed into more casual style. Nowadays, it has been developing into various uses in modern male clothes to show their characters.

• Fashion & Textile Research Journal
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• v.16 no.6
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• pp.954-960
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• 2014

This study surveyed high school girls in the Busan, Ulsan, and Gyeongnam areas to study how they wear school uniforms along with their satisfaction levels and demands in regards to functional school uniforms. This study presents data on the requirements for the development of winter school uniforms for high school girls with improved warmth functions. The findings are: First, high school girls purchased school uniforms of different brands and the purchase rates for three brands were 25% to 30% approximately. Most of them spent more than 300,000 KRW and less than 400,000 KRW on school uniforms purchases. Second, the greatest complaints by students about winter school uniforms were the ability to conduct routine activities and poor thermal insulation. The most popular bottom underwear for girls was underpants and leggings. The most popular top underwear was half-sleeved round neck t-shirts and running shirts. Third, a survey about uniform functionality showed that most students used and 'arm pit sweat absorbing pad', 'Waist size adjusting function, and 'inside pockets with zippers'. Satisfaction with functional uniforms was low: less than 3.5 in all questions. Fourth, students were favorable to develop functional uniforms to keep warm in the winter. The bottom needs to be warmer than the top and it is necessary to keep legs warm, especially the thighs and calves.

• Fashion & Textile Research Journal
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• v.20 no.4
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• pp.410-421
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• 2018

The study is designed to develop a educational basic pants patterns for men, and has been analyzed focusing on the university textbooks published since 2000. We also used CAD programs and virtual fitting programs to analyze the fitness of pants. To do this purpose, after choosing 7 Men's Wear textbooks, selected patterns were drawn and measured using PAD system and were compared and analyzed. Also, the appearance evaluation was examined through virtual fitting and then evaluated 21 male and female university students in their 20s. After supplementing the problems of the patterns in the existing textbooks, a pattern was developed and verified the fitness of the developed pattern. The results of comparing the proposed measurement items of each textbook for the pants pattern indicated a significant differences in terms of hip circumference of each pattern, which were between 96~105cm. A comparison of the drafting methods of each pattern showed the drafting methods for the crotch length, the front crotch extension, the back crotch extension were the difference. The results of appearance evaluation were pattern E presented the slimmest fit and pattern D presented the loosest fit. As a result of analysis of pants pattern, a waist circumference 82cm, a hip circumference 98cm, a crotch length 24cm, a pants length 104cm and a ham line width 46cm were most suitable. The development pattern was evaluated as superior to the existing pattern through the appearance evaluation of the virtual fitting.

• Journal of the Korean Society of Costume
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• v.53 no.5
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• pp.79-95
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• 2003

The purpose of this study is firstly to survey the social and cultural background of 20th century and women´s status, and to identify what the ideal body is like and what the elements of outer garment and underwear are and the techniques to incarnate the ideal beauty. Various papers are referenced for theoretical study and the elements and techniques of underwear are analyzed based on photographical materials. This paper concludes as follows. In 1960´s, ideal beauty was small bust, long legs, which showed extremely slim Mini-skirt look. Thinly or no padded brassiere were worn for small bust, and pants-style short panty girdles were popular as they used to wear pants frequently. Lycra replaced all the closures, bones, seams and gave freedom with light weight. In 1970´s, a natural human body without sex specific was in vogue. Therefore, the non-structural knits without a pad or lining or the shirts dress were widespread for a Natural look and the naturally molded brassiere or girdles were worn as the underwears. In 1980´s, the women with powerful muscle appear which emphasized liveliness and healthfulness. The body conscious represented by wide shoulder, plump breast, accented waist, small hips, and long legs has been embodied. Outer garments emphasized women power and healthy beauty with Power suit and Form-fitting style, and underwears made the breast plump with padded brassiere and emphasized waist and hips with waspie. In 1990´s, ideal beauty was slim body with big bust and the outer garments emphasized body line of women with Hourglass silhouette. Push-up bra which emphasizes the valley of breast and supports the breast upward and the control tights for slim waist, flat abdomen, small hips, and long and slim legs have been useful as underwears. Multi-functional micro-fiber has been ideal for sculpting women body.

• Korean Journal of Materials Research
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• v.27 no.3
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• pp.132-136
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• 2017

We synthesized potassium hexatitanate, ($K_2Ti_6O_{13}$, PT6), with a non-fibrous shape, by acid leaching and subsequent thermal treatment of potassium tetratitanate ($K_2Ti_4O_9$, PT4), with layered crystal structure. By controlling nucleation and growth of PT4 crystals, we obtained splinter-type crystals of PT6 with increased width and reduced thickness. The optimal holding temperature for the layered PT4 was found to be ${\sim}920^{\circ}C$. The length and width of the PT4 crystals were increased when the nucleation and growth time were increased. After a proton exchange reaction using aqueous 0.3 M HCl solution, and subsequent heat treatment at $850^{\circ}C$, the PT4 crystal transformed into splinter-type PT6 crystals. The frictional characteristics of the friction materials show that as the particle size of PT6 increases, the coefficient of friction (COF) and wear amounts of both the friction materials and counter disc increase.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.10
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• pp.65-72
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• 1998

The BTA drilling chip is better for deep hole drilling than other self-piloting with pad drilling chips because the large length to diameter ratio allows a unique cutting force dispersion and better supplies the high pressure fluid. Therefore the BTA is useful for many tasks, such as coolant hole drilling of large scale dies, as well as tube seat drilling, which is essential for the heat exchanger, and variable component drilling for automobiles. Deep hole drilling has several significant problems, such as hole deviation, hole over-size, circularity, straightness, and surface roughness. The reasons for these problems, which often result in quality short comings, are an alignment of the BTA drilling system and the unbalance of cutting force by work piece and tool shape. This paper analyzes the properties through an experiment which com¬pared single-edge BTA drills with multiple-edge BTA drills, as well as the shapes of the tools to cause an unbalance of cutting force, and its effect on the precision of the worked hole. Conclusions are as follows. 1) In SMSSC drilling, 60m/min of BTA with single and multi-edged tools proved the best cutting condition and the lowest wear character. 2) The roundness got a little worse as cutting speed was increased, but surface roughness was hot affected. 3) It was proved that the burnishing torque of both drills approached 26%. which is almost the same as the 24% insisted on by Griffiths, and the dispersion characteristic of the multi-edged BTA drill proved better than the single-edge BTA drill.