• Korean Journal of Materials Research
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• v.26 no.6
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• pp.311-319
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• 2016

In this study, an environment-friendly synthetic strategy to process zinc oxide nanocrystals is reported. The biosynthesis method used in this study is simple and cost-effective, with reduced solvent waste via the use of fruit peel extract as a natural ligation agent. The formation of ZnO nanocrystals using a rambutan peel extract was observed in this study. Rambutan peels has the ability to ligate zinc ions as a natural ligation agent, resulting in ZnO nanochain formation due to the presence of an extended polyphenolic system over the whole incubation period. Via transmission electron microscopy, successful formation of zinc oxide nanochains was confirmed. TEM observation revealed that the bioinspired ZnO nanocrystals were spherical and/or hexagonal particles with sizes between 50 and 100 nm.

• Journal of the Korea Institute of Building Construction
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• v.12 no.1
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• pp.73-86
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• 2012

In this research, the possible applicability of mixture blended with natural, crushed, and recycled fine aggregate are discussed. The fresh and hardened properties of mortar using blended fine aggregates are monitored depending on various blending ratio of fine aggregates. Newly developed ternary diagram was also utilized for better interpretation of the data. It was found that air content increased and unit weight decreased as recycled fine aggregate content increased. With moisture type processing of recycled fine aggregate, the mortar flow was not negatively affected by increase in the recycled fine aggregate content. The ternary diagram is found to be an effective graphical presentation tool that can be used for the quality evaluation of mortar using blended fine aggregate.

• Journal of the Korean Society of Industry Convergence
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• v.23 no.5
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• pp.727-733
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• 2020

Recently, reciprocating cryogenic pumps are mainly developed for small-and-mid sized fuel supply systems. Centrifugal type pumps are not actively developed. Most cryogenic submerged pumps are imported. For transportation, cryogenic liquefied natural gas requires the liquid pump technology that can works in extreme evironments. In order to transport liquefied natural gas, it is necessary to apply pump technology. This is the fundamental research for developing the submerged pump technology applicable to the transportation and storage system equipment of cryogenic liquefied system. It tries to secure basic design materials through reverse-engineering in the cryogenic submerged pump development. Regarding materials, STS-304 and STS-431 which are stainless materials widely used in the cryogenic area are applied. Aluminum alloy is applied to impeller and upper manifolder and the pump rotates at the high speed of 6,000rpm.

• Bulletin of the Korean Chemical Society
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• v.27 no.10
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• pp.1562-1566
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• 2006

Mesoporous silica films with three different pore sizes were prepared by using cationic surfactant, non-ionic surfactant, or triblock copolymer as structure directing agents with tetramethylorthosilicate as silica source in order to control the pore size and wall thickness. They were synthesized by an evaporation-induced self-assembly process and spin-coated on Si wafer. Mesoporous silica films with three different pore sizes of 2.9, 4.6, and 6.6 nm and wall thickness ranging from $\sim$1 to $\sim$3 nm were prepared by using three different surfactants. These materials were optically transparent mesoporous silica films and crack free when thickness was less than 1 m m. The photoluminescence spectra found in the visible range were peaked at higher energy for smaller pore and thinner wall sized materials, consistent with the quantum confinement effect within the nano-sized walls of the silica pores.

• Journal of the Korea Furniture Society
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• v.20 no.6
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• pp.575-580
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• 2009

This study was carried out to manufacture wooden vessels by small diameter wood and wasted wood of Castanea crenata Sieb. et Zucc, which has been largely planted in southern area. We made spice set, tea box set, cookie vessel set, bowl set and accessory set. With the development of edged tools, the human species has been able to fashion wood to change and enhance its environment - one only has to look at the history of all cultures to see examples of wooden artifacts and structures. Even with the development of synthetic materials and the progress of automated, mechanized production of wood and wood products, the raw material is still processed by traditional methods to meet a never-ending demand for products made from this most desirable natural material. Chestnut wood has high added value and natural color grain and is very useful for wooden vessel. Thinned low grade trees can be used to produce wooden vessel. Therefore this result can promote thinning and produce good forestation.

• Smart Structures and Systems
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• v.5 no.5
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• pp.517-529
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• 2009

This paper presents the development of a new Adaptive Tuned Dynamic Vibration Absorber (ATDVA) working with magnetorheological elastomers (MREs). The MRE materials were fabricated by mixing carbonyl iron particles with silicone rubber and cured under a strong magnetic field. An ATDVA prototype using MRE as an adaptable spring was designed and manufactured. The MRE ATDVA worked in a shear mode and the magnetic field was generated by a magnetic circuit and controlled through a DC power supply. The dynamic performances or the system transmissibility at various magnetic fields of the absorber were measured by using a vibration testing system. Experimental results indicated that this absorber can change its natural frequency from 35Hz to 90Hz, 150% of its basic natural frequency. A real time control logic is proposed to evaluate the control effect. The simulation results indicate that the control effect of MRE ATDVA can be improved significantly.

• Journal of the Korea Fashion and Costume Design Association
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• v.5 no.3
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• pp.15-23
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• 2003

Chestnut trees have been used as a dyeing material, which are grow naturally, are cultivated all the area of Korea. So, there is abundant amount of the materials and they have better colorfastness than other natural dyeing materials. But chestnut husk extract is good at silk and wool fabrics, not cotton fabrics. That's why many methods using chestnut extraction for dyeing are being studied. But most of them depend on treatment method with chemical material which doesn't fit with the aim, using natural materials. Therefore in this research, we used protein pre-treatment method which is dyeing chestnut husk extract after treating at cotton fabrics with bean sap. And we studied the effect of dyeability of chestnut husk extract to cotton fabrics. As a result of pre-treatment of bean sap at cotton fabrics, dyeability was increased. Besides laundering fastness, dry cleaning fastness, perspiration fastness and light fastness were almost increased.

• The Research Journal of the Costume Culture
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• v.9 no.2
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• pp.188-206
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• 2001

In 1990's, many collections, showing trends of restoration, took the hippie fashion as their main theme. Therefore, this study investigates the aspects of the hippie trend focusing on style, materials, colors shown in Mlan Collection, New York Collection, London Collection, Paris Collection, Tokyo Woman's Collection, and street fashions. 1. In style, the collections and street fashions exhibited layered look. 2. In materials, natural fibers were preferred s in 1960's . 3. In colors, natural hues such as black, white, and brown were primarily used, whereas vivid colors were used as accent. 4. In patterns, floral patterns were most extensively used as the flower is the symbol of Hippie. Animal patterns were also used. 5. In accessories, the Indian bred, a symbolic accessory of Hippie, was used with various materials. The hippie fashion in 1990's appeared not s a total fashion, but as an ancillary associate has the role of accentuation like hair-style, make-up, acessaries, etc.

• Journal of the Korean Society of Clothing and Textiles
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• v.28 no.11
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• pp.1353-1360
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• 2004

The purpose of this study is to develop a cultural products design of korean image using fabrics. The study is carry out in literature research methods and make sample product. We examine existing researches about cultural product design development to understand developed items, materials, and design directions. The brainstorming method and the established literature researches were used to obtain the design components of Korean image. A cultural products design was developed into the decorative structural details. The results can be summarized as follows: Korean image is pure, passive, gentle, small, and lasting life-force at weeds and wild flowers. Korean form is rounded curve and soft silhouette as streamy, not exaggerate. Korean color is not a finishing treatment, non-dyed natural color, or pastel, light greyish, and dull tone. Korean textile is a natural materials as linen, ramie, and coarse silk. Final sample products are table supplies, home goods and bed goods applying the sewing method of tuck, quilting, top-stitching, patch work, applique and embroidery.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.475-478
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• 2002

VA-LCDs is widely used for recent LCD productions owing to good viewing angle and high contrast. To apply for VA-LCDs, we have synthesized novel homeotropic alignment materials, which all generated high pretilt angles ($9^{\circ}$). The thermal stabilities of them were observed by thermogravimetric analysis (TGA). Transmittances of the NLC cell used the new alignment material were not changed before and after thermal annealing at $120^{\circ}C$ for 24hrs. In this work, the synthesis and alignment properties of new homeotropic alignment materials will be reported.