• Smart Structures and Systems
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• v.22 no.5
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• pp.495-508
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• 2018

Shape memory alloys (SMAs) exhibit superelasticity given the ambient temperature is above the austenite finish temperature threshold, the magnitude of which significantly depends on the metal ingredients though. For the monocrystalline CuAlBe SMAs, their superelasticity was found being maintained even when the ambient temperature is down to $-40^{\circ}C$. Thus this makes such SMAs particularly favorable for outdoor seismic applications, such as the framed structures located in cold regions with substantial temperature oscillation. Due to the thermo-mechanical coupling mechanism, the hysteretic properties of SMAs vary with temperature change, primarily including altered material strength and different damping. Thus, this study adopted the monocrystalline CuAlBe SMAs as the kernel component of the SMA braces. To quantify the seismic response characteristics at various temperatures, a wide temperature range from -40 to $40^{\circ}C$ are considered. The middle temperature, $0^{\circ}C$, is artificially selected to be the reference temperature in the performance comparisons, as well the corresponding material properties are used in the seismic design procedure. Both single-degree-of-freedom systems and a six-story braced frame were numerically analyzed by subjecting them to a suite of earthquake ground motions corresponding to the design basis hazard level. To the frame structures, the analytical results show that temperature variation generates minor influence on deformation and energy demands, whereas low temperatures help to reduce acceleration demands. Further, attributed to the excellent superelasticity of the monocrystalline CuAlBe SMAs, the frames successfully maintain recentering capability without leaving residual deformation upon considered earthquakes, even when the temperature is down to $-40^{\circ}C$.

• Journal of Fashion Business
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• v.2 no.1
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• pp.35-48
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• 1998

The purpose of this paper is to examine the street fashion, which is influenced by the youth culture in 1960s. Youth culture is the youth subculture which appeared multiform in the 1960s. 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. Youth cultures as youth subculture are symbolically expressed in their style which had strong characteristics of sub-fashion and anti-fashion, and which are different from mother fashion in shape. Therefore youth subculture fashion had an effect on street fashion in the 60s. The influence that the youth culture fashion had had on the street fashion is summarized as follows: Beats fashion was intelligency look on black dress, black polo-neck shirts, black trousers, black glasses and heavy black eyeliner. Mods fashion was neat style on Edwardian suit with narrow trousers, pointer-toeshoes and smooth croped hair. Folkis fashion was ethnic look, middle east asian look, peasant look, Indian style, south america look, gypsy style, natural materials, natural dying, tie-dye, beads and hand made ornaments. Rockers fashion was violence appearance categorized 'blue collar' on black leather jacket decorated with metal studs and hand-painted insignia, blue jeans and boots for motor bike. Swinging London & the Psychedelics fashion was blend mods look with pschedelic color and motive pattern. Hippie fashion was intermix pschedelic and natural or ethnic style. It was appear to be a meaningless, unpredictable assortment of diverse items and style. Faded and tattered jeans, army jackets, vintage hat, beads, embroidered headband, white sheets, diverse theatrical costumes, sandals or bare feet, granny dress, peasant blouse, blanket cape, tie-dye T-shirts and long hair. Greasers fashion was adorned black leather jacket with chains, fringing, badges, insignia and sleeves had been crudely ripped off. They came to be known wore jeans so soaked with oil. Skinheads fashion was aggressive working class identity with donkey jacket, jeans rolled up, collarless union shirts, heavy boots, braces and hair cropped short.

• Journal of the Korea Convergence Society
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• v.11 no.8
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• pp.153-158
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• 2020

In this study, the thermal and stress analyses were performed by applying a temperature condition of 100℃ at CPU cooler model. The value of heat flux value is shown to be the most at the lower rod area. The upper part becomes, the smaller the heat flow rate. The highest temperature is shown at the bottom of the CPU cooler model. Overall, the upper part becomes, the smaller the temperature becomes. Based on the temperature analysis, the thermal deformation caused by expansion, the deformation becomes smaller as the upper part of the overlapping plates. The great deformation happens at the bent area of the small rod as the lower part of model and the least deformation is shown at the lowest floor of model. In addition, the maximum thermal stress of 570.63 MPa happens at the floor below model. The stress is shown to decrease as the upper part of the overlapping plates becomes. But the stress is shown to increase somewhat at the middle part of model. By applying the study result on the thermal and stress analyses of CPU cooler, this study is seen to be suitable for the aesthetic convergence.

• Journal of the Korea Fashion and Costume Design Association
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• v.9 no.2
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• pp.31-48
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• 2007

The purpose of the this study is to make a historical review of changes in the structural decorations of men's costume from ancient times to modern times and to provide basic materials for developing handicraft decoration techniques and sewing methods in contemporary fashion. Their gorgeousness of collars and sleeves reached its peak along with the exaggerated expression of the human body during the Renaissance when people were free from Christian traditions of the Middle Ages and pursued human pleasures. Huge and decorative collars gave great dignity and formality to the wearer. Sleeves were slim and cuffs were small or nonexistent after the French Revolution. Various decorated pockets had been developed since pockets began to be attached to coats in the 17th century. Pockets were at the bottom of coat in the late 17th century, but they were gradually placed much higher on the coat. Buttons began to be used as the tool for sticking fast body to clothes in the 12th century and became extremely sumptuous accessories in the $16th{\sim}18th$ centuries. Men's clothes were simpler and more practical after the French Revolution. The result was that decorative buttons begun to disappear and metal buttons came out for practical purpose. The number of buttons worn on sleeves was also noticeably reduced. This research suggested the possibility that various decoration techniques could create the unique details in the each part of clothes. In order to develop high value-added products, we need to study various decoration-sewing methods and put to practical use them for creative fashion design.

• International Journal of Industrial Entomology and Biomaterials
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• v.25 no.2
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• pp.209-213
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• 2012

The propolis was collected from the whole part of Korea Peninsula, such as central, southern, and Jeju island, to analyze the general composition including total flavonoid and phenolic contents, heavy metals, colors, amino acids, and crude lipid. The total flavonoid and phenolic contents of middle region in Korea Peninsula (4.26% and 13.06 g/100 g gallic acid) were higher than southern region (2.53%, 10.9 g/100 g gallic acid) and Jeju island (0.03%, 7.22g/100 g gallic acid), respectively. The heavy metals contents showed that Zn contents were found in $0.44{\pm}0.2ppm$ and a harmful heavy metal such as Cr, Cd, Pb, Ni, Cu, As, and Hg were not detected at all in our experiment. The colors of extracted propolis showed a various spectrum from yellow to red purple. Various amino acids were also detected as proline, valine, methionine and the average crude lipid contents of propolis were 42.4%. All data collected in South Korea were very first executed in our institution for the purposes of utilizing and developing the industrial insects, honeybees as well as silkworm.

• Ocean and Polar Research
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• v.36 no.4
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• pp.373-381
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• 2014

Korea contract Mn-nodule field in the NE equatorial Pacific is composed of seven sectors with average water depths of 4,513-5,025 m. Of the various factors controlling the properties of Mn-nodule, it seems that water depth is likely connected to the chemical composition and occurrence of nodules. To test whether such an assumption held in each sector, we reviewed previous research data accumulated since 1994 for one of the northern sectors (hereafter KR1) where there are stark contrasts in water depth. High-resolution seabed mapping clearly separates a northern part (KR1N) from a deeper southern part (KR1S), cutting across in the middle of the KR1. In addition, significant volcanic activities forming numerous seamounts are distinctive especially in KR1N. In terms of nodule occurrence, manganese nodules in KR1S are comparatively larger (2-4 cm) with a discoidal shape, while those in KR1N are generally small (<2 cm) with poly-lobate and irregular shapes. Nodules in KR1N also have lower Co, Cu, Mn and Ni, and higher Fe contents. The spatial separation in nodule characteristics might be caused by volcanic activities in KR1N rather than water depth contrast. During the formation of the seamounts in KR1N, rock fragments and volcanic ashes as new nuclei of the nodules would have been continuously generated. As a result, the nodules could not grow larger than 2 cm and display the shapes of a newbie (i.e., irregular and poly-lobate shapes). Moreover, significant Fe supply from volcanic activities probably decreases the Mn/Fe ratio, which may lead to the KR1 nodules being misinterpreted as a hydrogenic in origin compared to other sectors where a high Mn/Fe ratio is present.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.1268-1271
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• 2005

This paper proposes a compact-sized surface myoelectric sensor for myoelectric hand prosthesis. To fit the surface myoelectric sensor in the socket of the myoelectric hand prosthesis, the sensor should be a compact size. The surface myoelectric sensor is composed of a skin interface and a single processing circuit that are mounted on a single package. Since the skin interface has one reference and two input electrodes, and the reference electrode is located in middle of two input electrodes, we propose two types of sensors with the circle- and bar-shaped reference electrode, but all input electrodes are the bar-shaped. The metal material used for the electrodes is the stainless steel (SUS440) that endures sweat and wet conditions. Considering conduction velocity and median frequency of the myoelectric signal, we select the inter-electrode distance (IED) between two input electrodes as 18mm, 20mm, and 22 mm. The signal processing circuit consists of a differential amplifier with band pass filter, a band rejection filter for rejecting 60Hz power-line noise, amplifiers, and a mean absolute value circuit. We evaluate the proposed sensor from the output characteristics according to the IED and the shape of the reference electrode. From the experimental results we show the surface myoelectric sensor with the 18mm IED and the bar-shaped reference electrode is suitable for the myoelectric hand prosthesis.

• Journal of Magnetics
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• v.17 no.2
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• pp.145-152
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• 2012

Patients who underwent hip arthroplasty using the conventional fat suppression technique (CHESS) and a new technique (IDEAL) were compared quantitatively to assess the effectiveness and usefulness of the IDEAL technique. In 20 patients who underwent hip arthroplasty from March 2009 to December 2010, fat suppression T2 and T1 weighted images were obtained on a 3.0T MR scanner using the CHESS and IDEAL techniques. The level of distortion in the area of interest, the level of the development of susceptibility artifacts, and homogeneous fat suppression were analyzed from the acquired images. Quantitative analysis revealed the IDEAL technique to produce a lower level of image distortion caused by the development of susceptibility artifacts due to metal on the acquired images compared to the CHESS technique. Qualitative analysis of the anterior area revealed the IDEAL technique to generate fewer susceptibility artifacts than the CHESS technique but with homogeneous fat suppression. In the middle area, the IDEAL technique generated fewer susceptibility artifacts than the CHESS technique but with homogeneous fat suppression. In the posterior area, the IDEAL technique generated fewer susceptibility artifacts than the CHESS technique. Fat suppression was not statistically different, and the two techniques achieved homogeneous fat suppression. In conclusion, the IDEAL technique generated fewer susceptibility artifacts caused by metals and less image distortion than the CHESS technique. In addition, homogeneous fat suppression was feasible. In conclusion, the IDEAL technique generates high quality images, and can provide good information for diagnosis.

• Journal of the Korean Ceramic Society
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• v.39 no.6
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• pp.576-581
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• 2002

In order to simultaneously vitrify the ton Exchange Resin(IER) and Dry Active Waste(DAW) generated from the Nuclear Power Plants, a vitrification pilot test was conducted using an induction cold crucible melter. The PCT result evaluating the chemical durability of the vitrified from showed that the final glass was more durable than the benchmark glass. Liquidus temperature for the final vitrified form was 1048 K(775$\^{C}$) fur heat treatment experiments. The value of the compressive strength for the vitrified form was ninety times higher than the regulation limit, 34 kg/㎠. The glasses on bottom, middle and top of the CCM were homogeneous with no secondary phase. The precipitation of the magnetic metal phase was able to be avoided by simultaneously fEeding of DAW with IER containing strongly reducing organics. Volume reduction factor of 74 was achieved through the vitrification Pilot test for mixed waste.

• The Journal of Advanced Prosthodontics
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• v.2 no.4
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• pp.117-121
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• 2010

PURPOSE. The present study was intended to evaluate the effect of soldering techniques with infrared ray and gas torch under different gap distances (0.3 mm and 0.5 mm) on the tensile strength and surface porosity formation in Ni-Cr base metal alloy. MATERIALS AND METHODS. Thirty five dumbbell shaped Ni-Cr alloy specimens were prepared and assigned to 5 groups according to the soldering method and the gap distance. For the soldering methods, gas torch (G group) and infrared ray (IR group) were compared and each group was subdivided by corresponding gap distance (0.3 mm: G3 and IR3, 0.5 mm: G5, IR5). Specimens of the experimental groups were sectioned in the middle with a diamond disk and embedded in solder blocks according to the predetermined distance. As a control group, 7 specimens were prepared without sectioning or soldering. After the soldering procedure, a tensile strength test was performed using universal testing machine at a crosshead speed 1 mm/min. The proportions of porosity on the fractured surface were calculated on the images acquired through the scanning electronic microscope. RESULTS. Every specimen of G3, G5, IR3 and IR5 was fractured on the solder joint area. However, there was no significant difference between the test groups (P > .05). There was a negative correlation between porosity formation and tensile strength in all the specimens in the test groups (P < .05). CONCLUSION. There was no significant difference in ultimate tensile strength of joints and porosity formations between the gas-oxygen torch soldering and infrared ray soldering technique or between the gap distance of 0.3 mm and 0.5 mm.