• 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.

• Journal of Fashion Business
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• v.5 no.2
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• pp.15-34
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• 2001

Ornaments are accessories for the decoration of the body or dress. They aren't unavoidably required one, but serve to make one's dress perfect as decorative industrial art objects. In Morocco, ornaments were initially used as a sign of social position or the class or an incantatory symbol. In effect, they were originally employed to adjust one's dress, not just for decoration, and they were of use for household economy. Gold, silver and handcraft available for exchange were a means of increasing one's property and an indication of social standing and wealth. In particular, the dress and jewelry of a bride was a measure of her family's wealth, regarded as a symbol of her chastity and value. The ornaments symbolically back up people's faith in supernatural power, and their real value is based on implicit form or way of decoration, not the external shape. Specifically, there is a tendency to use the form of animal as a protector, not one to frighten people. In the artistic tradition of Morocco, fish pattern stands for water and rain, and eagle and bird are considered to be related to fate. Scorpion and lizard are depicted as an inquirer of sun, and snake is a symbol of abundance and sexual instinct, being viewed to have an ability to cure disease. Turtle pattern is a symbol of saint because it protects one from the evil. The ornaments are made of gold, silver, amber, clam, garnet, glass, nielle, enamel, glaze, coral or tree, and symbolic patterns are used, including hand(a symbol of five numerals), turtle, lizard, scorpion, eye, triangle, bird and eggs. They are very big and diverse, being categorized into ornaments for the head or the chest, neckless, fibula, earring, bracelet and ring. For Moroccans, make-up is a sort of instinctive behavior to meet aesthetic and sexual desire. They also wear make-up for practical purpose of protection, intentionally inflict a wound on the skin for ceremonial or religious purpose, paint the skin with pigment, or have the part of the body tattooed for incantatory purpose. All this actions are regarded as make-up. The raw material of cosmetics is aker, a vegetable dye. They get the lips or cheeks turn red and paint eyebrows with yellow saffran powder to have a bad devil lose its strength. Tattooing is mainly done by women and viewed as a sign of their value or social organization they belong to. Sometimes that is used to represent a woman's being old enough to marry or getting married already or the frequency of marriage. Besides, tattoo is believed to prevent or remedy loose bowels or cough, depending on its location or pattern, and they often change tattoo according to the change of beauty art.

• Korean Journal of Materials Research
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• v.18 no.6
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• pp.339-346
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• 2008

Single-crystal $ZnIn_2S_4$ layers were grown on a thoroughly etched semi-insulating GaAs (100) substrate at $450^{\circ}C$ with a hot wall epitaxy (HWE) system by evaporating a $ZnIn_2S_4$ source at $610^{\circ}C$. The crystalline structures of the single-crystal thin films were investigated via the photoluminescence (PL) and Double-crystal X-ray rocking curve (DCRC). The temperature dependence of the energy band gap of the $ZnIn_2S_4$ obtained from the absorption spectra was well described by Varshni's relationship, $E_g(T)=2.9514\;eV-(7.24{\times}10^{-4}\;eV/K)T2/(T＋489K)$. After the as-grown $ZnIn_2S_4$ single-crystal thin films was annealed in Zn-, S-, and In-atmospheres, the origin-of-point defects of the $ZnIn_2S_4$ single-crystal thin films were investigated via the photoluminescence (PL) at 10 K. The native defects of $V_{Zn}$, $V_S$, $Zn_{int}$, and $S_{int}$ obtained from the PL measurements were classified as donor or acceptor types. Additionally, it was concluded that a heat treatment in an S-atmosphere converted $ZnIn_2S_4$ single crystal thin films into optical p-type films. Moreover, it was confirmed that In in $ZnIn_2S_4$/GaAs did not form a native defects, as In in $ZnIn_2S_4$ single-crystal thin films existed in the form of stable bonds.

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.4
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• pp.409-417
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• 2014

Since the oil price has been significantly jumped for recent some years, the diesel engine of the merchant ship has been mainly used the heavy oil of low quality. Thus, it has been often exposed to severely corrosive environment more and more because temperature of the exhaust gas in a combustion chamber is getting higher and higher with increasing of using the heavy oil of low quality. As a result, wear and corrosion of most parts surrounded with combustion chamber is more serious compared to the other parts of the engine. Therefore, an optimum weldment for these parts is very important to prolong their lifetime in a economical point of view. In this study, four types of filler metals such as Inconel 625, 718, 1.25Cr-0.5Mo and 0.5Mo were welded with SMAW and GTAW methods in the forged steel which would be generally used with piston crown material. And the corrosion properties of weld metal, heat affected zone and base metal were investigated using electrochemical methods such as measurement of corrosion potential, anodic polarization curves, cyclic voltammogram and impedance etc. in 35% H2SO4 solution. The weld metal and base metal exhibited the best and worst corrosion resistance in all cases of filler metals. In particular, the weld metal welded with filler metals of Inconel 718 revealed the best corrosion resistance among the filler metals, and Inconel 625 followed the Inconel 718. Hardness relatively indicated higher value in the weld metal compared to the base metal. Furthermore, Inconel 625 and 718 indicated higher values of hardness compared to 1.25cr-0.5Mo and 0,5Mo filler metals in the weld metal.

• Corrosion Science and Technology
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• v.13 no.1
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• pp.28-35
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• 2014

Recently, the fuel oil of diesel engines of marine ships has been increasingly changed to heavy oil of low quality as the oil price is getting higher and higher. Therefore, the spiral gear attached at the motor of the oil purifier which plays an important role to purify the heavy oil is also easy to expose at severe environmental condition due to the purification of the heavy oil in higher temperature. Thus, the material of the spiral gear requires a better mechanical strength, wear and corrosion resistance. In this study, the heat treatment(tempering) with various holding time at temperature of $500^{\circ}C$ was carried out to the alloy of Cu-7Al-2.5Si as centrifugal casting, and the properties of both hardness and corrosion resistance with and without heat treatment were investigated with observation of the microstructure and with electrochemical methods, such as measurement of corrosion potential, cathodic and anodic polarization curves, cyclic voltammogram, and a.c. impedance. in natural seawater solution. The ${\alpha}$, ${\beta}^{\prime}$ and ${\gamma}_2$ phases were observed in the material in spite of no heat treatment due to quenching effect of a spin mold. However, their phases, that is, ${\beta}^{\prime}$ and ${\gamma}_2$ phases decreased gradually with increasing the holding time at a constant temperature of $500^{\circ}C$. The hardness more or less decreased with heat treatment, however its corrosion resistance was improved with the heat treatment. Furthermore, the longer holding time, the better corrosion resistance. In addition, when the holding time was 48hrs, its corrosion current density showed the lowest value. The pattern of corroded surface was nearly similar to that of the pitting corrosion, and this morphology was greatly observed in the case of no heat treatment. It is considered that ${\gamma}_2$ phase at the grain boundary was corroded preferentially as an anode. However, the pattern of general corrosion exhibited increasingly due to decreasing the ${\gamma}_2$ phase with heat treatment. Consequently, it is suggested that the corrosion resistance of Cu-7Al-2.5Si alloy can be improved with the heat treatment as a holding time for 48 hrs at $500^{\circ}C$.

• Tunnel and Underground Space
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• v.23 no.3
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• pp.180-191
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• 2013

The purpose of this research was to find an optimal quarrying for marble by analyzing the applicability and the work efficiency of a chain saw machine newly introduced in the underground Baekwoon mine. From the test results of the physical properties of Baekwoon marble, which affects the efficiency of rock cutting, it was found to have similar physical characteristics as the ones which are now being produced in the other areas in Korea. And especially it shows isotropic property, which can be thought to be advantageous as a dimensional stone. To check the long-term quality of the marble as a stone material, several tests such as corrosion resistance test and abrasion test were carried out. It was found to be vulnerable to acid rain with decrease of weight and seismic wave velocity after applying artificial rain at pH 5.6 for 50 times. The percentage of wear from abrasion test was 22.67%. The working time and cutting speed of the chain saw machine were recorded and analyzed during the test-run at the quarry. The overall work cycle was assorted into 9 unit operations and the operating time per each unit was drawn. The operating times for the two cutting patterns, which could be possibly applicable to the work site, were compared. The results indicated that the pattern B, that the cutting sequence was set to minimize the movement of the machine, showed 6% less working hours than the pattern A, which first cuts the outer boundary. With cutting pattern analysis, the ore body in the Baekwoon mine was 3 dimensionally modeled and a quarrying plan considering the existing conditions of the marble was suggested.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.7
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• pp.8-15
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• 2019

In this study, we synthesized a calcium sulfonate complex grease and a lithium complex grease to investigate their physical, rheological and tribological properties. The thermal stability of the calcium sulfonate was higher than $300^{\circ}C$ and the lithium complex grease was $245^{\circ}C$ in the dropping point test. In the grease viscosity measurement, the calcium sulfonate complex grease was measured as $7.0Pa{\cdot}s$ and the lithium complex grease was as $4.5Pa{\cdot}s$. Therefore, it was confirmed that the calcium sulfonate complex grease is superior to the lithium complex grease in terms of thermal stability and cohesiveness. In the 4-ball wear test, the calcium sulfonate complex grease was measured to be 0.43 mm and the lithium complex grease to 0.85 mm. In the 4-ball extreme pressure test, calcium sulfonate complex grease was measured as 620 kgf and the lithium complex grease was as 125 kgf. Therefore, it was confirmed that the calcium sulfonate complex grease is superior to the lithium complex grease in abrasion resistance and load-bearing property. It was found that the calcium sulfonate complex grease is more effective than the lithium complex grease in the lubrication at high temperature and high load.

• Journal of the Korean Society of Clothing and Textiles
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• v.29 no.12 s.148
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• pp.1535-1545
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• 2005

The study aimed firstly, to develop the women's bodysuit sleeve block construction method adopting the appropriate pattern reduction rates according to the fabric stretch property. Secondly, the details applied to the bodysuit sleeve block drafting (Dr the educational and industrial usage were proposed. For these, several distinguishing bodysuit sleeve pattern making methods(i.e. Joseph-Armstrong: T1, Shoben & Ward: T2, Esmod: T3 and Mixed Joseph-Armstrong: T4) were analyzed and divided into two categories that adopt 1) the equally (i.e., T1) and 2) the differently(i.e., T2, T3 & T4) distributed front and back armhole length measurements. Women's sleeve samples were made for the research using the same stretch fabric($50\%\;and\; 70\%$ in wale and course each) to the previous research. A group comprising 5 relevant experts evaluated the fit and comfort features of the samples. Experiments analyzed the appearance of sleeve samples focused on total 13 evaluation parts(including the front/side/back fit tolerance, sleeve centre line, sleeve length, appropriateness of the sleeve appearance balanced with the bodysuit and etc.): and performed the comfort test evaluating three kinds(vertical-front/vertical-side/ horizontal) of arm movements. The most appropriate bodysuit sleeve to fulfil the original aims of the study was suggested. The findings and suggestions throughout the study were: 1) the measurements and required reduction rates for the bodysuit sleeve block developed: outer sleeve length (with 1.0 RR), crown height(with 0.7 RR), front and back armhole lengths measured on the bodysuit blocks ($0\%$ ease amount), elbow width(0.9/0.95 RR), wrist girth measurements(from $12\%\;to\;18\%$ tolerances can be given to): and 2) the differently distributed front and back armhole length measurements resulted in the better fit and comfort through the research.

• Journal of Environmental Health Sciences
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• v.17 no.2
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• pp.54-66
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• 1991

As a result of measuring illumination and making up a question at home visit directly by investigator who trained over twenty days period from October 4 to 24, 1990, in order to render help which illumination problem against house, society against eyes or framing of health instruction potgram by seizing natural lighting actual conditions of house and actual conditions of wearing spectacles and by investigating interrelationship, I can summarize as follows. 1) In property of investigation subject, woman 66.9%, In an age, the twenties was largest of 27.4%, the forties was 20.2%, the fifties was 18.6%, the thirties was 17.4%. In academic career, those of upper secondary school grauates was largest of 28.6%, those who possess university career was 25.9%, those who middle school career was 20.9%, decoding of Korean alphabet was 2%. 2) By a residence area, a big city was 43.3%, farming and fishing villages were 20.3%, the rest was a small town and the administrative office of town, township. In positon of house, the middle area was 43.6%, resident of suburb area was 38.0%. In form of house, a Korean-style house was 40.8%, a western-style house was 34.8%, an apartment house was 11.0%. In the a standard of living, the middle classes 77.2%, the lower classes were 15.3%. In residential house unit of area, from 21 to 30 unit of area was largest of 31.5%, from 10 to 20 unit of area was 19.9%, from 31 to 40 was 18.7%. 3) The wearing spectacles rate of study user was 44.1%. By the area, those who wearing spectacles was more than a half of 50.8% in the resident of big city area. As passing from the farm area to the city, that is being resident of big city was high wearing spectacles rate. In position of house, as being residence in central street showed high wearing spectacles rate. (central street was 51.5%, the middle area was 44.5% and the suburb area was 40.1%.) It seemed similarity difference a variable by position of house from wearing spectacles in standard of 1%. By form of house, wearing spectacles rate those who resident in apartment house was 49.5%, that rate those who resident in a western-style house was high of 49.0%, that rate those who resident in a Korean-style house was the lowest 39.0%. By social position of resident in room, in students case who study showed very high, as university students were very high of 62.3% idn wearing spectacles rate, middle and high school students 'were 50.0%, members of society were 47.6%, workers 20.3%. It seemed similarity difference from academic career in standard of 1%. By an age, the thirties was high of 54.1% in wearing spectacles rate, the twenties was 43.2%, the teenage was the lowest of 11.8%. 4) In illumination of study, over 200Lux was high of 40.1%. but below 99Lux which inappropriate illumination to see the books was 32.4%. Average by area, below 99Lux was 22.7% and over 400Lux was 50.0% in case of wooden floor. As examine by area, below 99Lux was high of 27.0% a case of wooden floor in the big city area, it was not good in illumination passing from the farm area(15.0%) to the city(19.0%). Average illlumination by area of the main living room below 99Lux was high of 37.5%, less than 200Lux was 58.5% of whole. In general, illumination of the main livingroom was inappropriate. By area, the big city was 32.5% below 99Lux, the middle and small city area were 33.8%, town and township area were 45.0%, farming and fishing area were 42.8%. By area, in the big city, illumination of study was 52.5% over 200Lux and 28.9% below 99Lux. In case of the middle and small city, study user of below 99Lux was 38.8% and over 200Lux was 46.9%. In case of the seat of town township, below 99Lux was 34.1% and over 200Lux was 39.7%. In case of farming and fishing area, illumination of study was 33.4% below 99Lux and 48.4% over 200Lux. It tends to high rate of inappropriate illumination. 5) By position of house, in case of wooden floor, less than 100Lux was 24.5% in central street. It was bad illumination than others position of house. In case of the main livingroom, less than 100Lux was 40.4% in the suburb area. It was bad iliumnation than others position of house. In case of study, less than 100Lux was 35.4% in the middle area, it was worse in illumination. In case of the main living room, is seemed similarity difference in standard of 1%. 6) By form of house, in case of wooden floor, illumination of less than 100Lux was 23.8% in a western-style house, it was bad illumination than others form of house. In case of the main livingroom, illumination of less than 100Lux was 47.4% in a Korean-style house, it was remarkably bad illumination than others form of house. In case of study, a Korean-style house was 38.8%, it was very bad illumination than others form of house. In case of the main livingroom and study, it seemed similatrity difference each as P < 0.01 and P < 0.05 in standard of 1%. 7) The wearing spectacles rate of those who use room of illumination over 400Lux was 40.7%, and that of those who use room of illumination less than 100Lux was 28.1%. It seemed similarity differecce in standard of 1%. 8) In period of wearing spectacles, 21.3% of total investigator-highest-was from before five years, 8.6% was from before three years. Among those who use of illumintion less than 99Lux, 34.0% began to wear spectacles from before two years 31.7% was from before five years, 30.3% was from before four years. It seemed similarity difference from period of wearing spectacles by illumination in standard of 1 %. 9) Among cause which sight grow worse, the first was that it was each 33.2% and 27.4% in response rate because watch TV nearly to wearing spectacles person and non-wearing person. The second was that a lot of seeing books was 25.3% in wearing spectacles person and response rate for dark illumination was 7.4% in nonwearing spectacles person. It seemed similarity difference in standard of 1%. (P < 0.01). 10) In experience which take medicine good for eyes, it was 50.1% in wearing spectacles person and 8.5% in non-wearing spectacles person. It seemed similarity difference in standard of 1%(P < 0.01). As we have seen above, inappropriate illumination can be a cause of wearing spectacles. Nevertheless, actually, is realities to indifferent against illumination of house. So it must learn knowledge about health obstacle of illumination through society instruction and school eduction against students as well as general residents. In case that natural lighting is inappropriate structural of house, we must be able to maintain appropriate illumination through artificial illumination. And so eyes which is core of human life have to be protected, related the authorities, related group, and all health medical personnel will organically cooperate with and make efforts.