• Journal of the Korean Society of Safety
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• v.18 no.4
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• pp.92-97
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• 2003

The purpose of this study is heavy metal absorption of recycled PET(poly ethylene terephatalate) NWF(non woven faric). The results of test are summarized as follows; Heavy metal abworption rates in Ni ions were higher then Zn and Cu ions, whereas heavy metal absorption rates by sulfonation times were not different. The heavy metal absorption times have a higher tendency from 60 min to 120 min. There were significant negative correlations among the amount used CSA(Chloro Sulfuric Acid) and the amount of absorption Zn(r = -0.33784, p < 0.05), Cu(r = -0.61177, p < 0.01) ions, whereas correlations between heavy metal absorption rates and sulfonation times were not significant. There were significant positive correlations among the amount of absorption Zn ions and the amount of absorption Ni(r = 96475, p < 0.014), Cu(r = 0.51614, p < 0.01) ions, likewise the positive correlations between the amount of absorption N ions and the amount of absorption Cu(r = 0.54766) ions were significant(p < 0.01).

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.9
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• pp.1235-1240
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• 2010

Wire-woven Bulk Kagome (WBK) is fabricated by assembling helically formed wires in six directions. To date, WBK samples have been assembled manually. For industrial application, the assembly process must be automated. Furthermore, if WBK is to be fabricated using flexible wires that cannot maintain their helical shape during fabrication, a specialized automatic machine, i.e., a loom needs to be developed. In this work, we designed and constructed a loom for fabricating WBKs using flexible wires. This loom is operated by one rotation of the upper plate, two translations of the insertion device, and insertion of wires. So-called "comb devices" are placed between multiple layers of Kagome nets to prevent the wires that are already in place from getting entangled with those that are being inserted. This loom can be also used to fabricate semi-WBKs composed of helically formed wires and rigid straight wires.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.4
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• pp.353-359
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• 2009

Wire-woven Bulk Kagome (WBK) is a new truss type cellular metal fabricated by systematic assembling of helical wires in six directions. In this work, the experiments of mechanical behaviors of WBK cored sandwich panels subjected to bending load were performed and the results were compared with those by the corresponding analytic solutions. And also, finite element simulations were performed to validate the optimal design according to the analytic solutions. It is found the sandwich panel with WBK core performed excellently in terms of energy absorption and deformation stability after the peak point as well as the load capacity.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.138-143
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• 2008

Recently, a new periodic cellular metal(PCM) named as Wire wove Bulk Kagome(WBK) was introduced. Based on the shape of tetrahedra composing a WBK, WBKs are classified into two types, namely, concave and convex type. They are easily differentiated by changing the assembling sequence. The effect of geometrical parameters such as the wire diameter, strut length and number of layers on the compressive behavior of concave type WBK has already been investigated. In this work, the similar works were performed with the convex type WBKs. It was shown that the compressive strength of the convex type WBK was quite similar to that of the concave type. The compressive strengths of convex type specimens also depend on the slenderness ratio, but a little different from those of concave type specimens in the detailed behavior. And densification occurs earlier than the concave type WBK.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2000.11a
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• pp.183-186
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• 2000

A new textile metal matrix composite fur electronic packaging was developed and characterized. The thermal management materials consist of a plain woven carbon fabric as reinforcement and pure aluminum as matrix. The finite element method has been utilized in the analysis of thermal stress between the constituent components of packaging. The prototype part was manufactured by the liquid pressurizing method. The composite has CTE values of 4 to $5{\times}10^{-6}\;^{\circ}C^{-1}$10 in the range of $25^{\circ}C$ ~ 175$^{\circ}C$, resulting in good agreement with electronic materials such as Si and GaAs.

• Journal of the Korean Society of Costume
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• v.58 no.9
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• pp.129-141
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• 2008

Jikgeum(woven with supplementary golden wefts) hyungbae(rank badge) of danryung(official uniform) excavated from Im Backryung'tomb($1498{\sim}1546$) of the Joseon dynasty($1392{\sim}1910$) at Goyang, Gyunggi-Do in 2007, was in a critical condition because of serious collapse of substrate in metal thread. For conservation of hyungbae, metal thread was examined by different scientific methods(Light Microscope, Scanning Electron Microscope and Energy Dispersive X-Rray Spectrometry(SEM-EDS), Fourier Transform Infrared Spectroscopy(FT-IR)). Analytical data showed that metal thread was gilt membrane strip composed of gold leaves and proteinaceous substrate which was probably parchment. To protect collapse of substrate, 1% solution of Paraloid B-72 was infilterated into substrate for consolidation of substrate and it was adhered to warp of fabric in hyungbae, before wet cleaning. After wet cleaning, the most of the gold leaves were restored, which was confirmed by both the examination with the naked eye and the microscopic examination.

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.462-465
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• 2002

물에 용해되어 있는 금속이온의 분리를 위한 선택성이 있는 분리 막의 개발은 환경오염이 날로 심각해지고 있는 오늘날에 환경오염의 개선, 에너지절약, 자원의 재활용 등 문제를 해결함에 있어서 아주 중요한 작용을 하게 될 것이다. 물에 용해되어 있는 금속이온을 선택적으로 분리하기 위해 일반적으로 캐리어(carrier)를 함유한 Carrier-Facilitated Transport Membrane (CFM)을 이용하게 되는데, 이 방면에 대한 연구는 주로 유기 상에 용해되어 있는 캐리어를 microporous한 필름에 지지하게 하는 방식으로 만들어진 Supported Liquid Membrane (SLM) 혹은 Elusion Liquid Membrance (ELM)의 개발에 대한 팽대한 연구가 이루어 졌다(1). (중략)

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.12
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• pp.49-55
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• 2020

In order to improve the electromagnetic shielding rate of Carbon Fiber (CF), it was produced using the nickel nano-powder impregnating method. Using two types of nickel powder having thicknesses of 50 ㎛ and 100 ㎛, and a thermoplastic elastomer resin, a compound containing 10-20% nickel content was mixed and then manufactured through an extruder. The CF coated with the compound was woven and manufactured using a 1-ply specimen. The final nickel content of the specimen was verified using TGA and the distribution of nickel powder on the CF surface was verified using SEM. The metal shows a high shielding rate in the low-frequency band, but the shielding rate decreases at higher-frequency bands. The CF improves at the higher frequency band, and metals reflect electromagnetic waves while carbon absorbs electromagnetic waves. The study of shielding materials, which are stronger and lighter than metal, by using CF lighter than metal and enabling the shielding rate from low-frequency band to high-frequency band, confirmed that the larger the area coated with nickel nano-powder, the better the electromagnetic shielding performance. In particular, CF coated with a thickness of 100 ㎛ has a shielding rate similar to that of copper and can also be used for EV/HEV automotive cables and other applications in the future.

• Journal of the Korean Society of Costume
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• v.62 no.7
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• pp.41-53
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• 2012

Hwangnamdaechong Tomb (The 98th tomb in Hwangnam-dong), one of the royal tombs located around the area of royal tomb of King Michu in Hwangnam-dong, Gyeongju, is currently designated as Historic Site No. 40. It is assumed that Hwangnamdaechong Tomb is a royal tomb of the early 5th century. This study aims to examine the fabric relics excavated from Hwangdamdawchong Tomb and currently housed in Gyeongju National Research Institute of Cultural Heritage. The types of fabrics excavated from Hwangdamdawchong Tomb include plain silk, warp-faced compound woven silk, and hemp cloth. Most of these fabrics are adhered to metal products that became rusty. Plain silk found in Hwangnamdaechong Tomb can be divided into four types by its weaving method. Geum excavated from Hwangnamdaechong Tomb is typical Gyeong Geum that uses colored warp for its base and pattern. It is plain Gyeong Geum that the binding weft and warp is plain woven. Although there are a lot of Gyeong Geum fabrics whose colors are hard to define due to yellowing after long years, there are still many fabrics whose color such as purple, red, blue, and green can be identified. As literatures have shown that p cloth as well as silk were frequently woven during Silla dynasty, tremendous amount of hemp cloth was excavated. Most of the hemp cloth has S-twist in the warp and 8-12 seung degree of delicacy.

• Journal of Electrochemical Science and Technology
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• v.12 no.1
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• pp.58-66
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• 2021

Spiral-wound woven wire meshes packed bed rotating cylinder electrode was used for the simultaneous removal of cadmium (Cd) and copper (Cu) from a binary solution. The effects of weight percent of each metal on the removal and current efficiencies were studied at an operating current of 345A, while the effect of current on the removal efficiency of both metals was investigated at three levels of current (240, 345.and 400 mA). The experiments were carried out at constant rotation speed 800 rpm, pH = 3, and a total concentration of metals (500 ppm). The results showed that the removal efficiency of copper increased from 89% to 99.4% as its weight percent increased from 20% to100%. In a similar fashion, the removal efficiency of cadmium increased from 81% to 97% as its weight percent increased from 20% to100%. The results confirmed that the removal efficiency of any metals declined in the presence of the other. Increasing of current resulted in increasing the removal efficiency of both metals at different weight percents. The results confirmed that current efficiencies for removing of copper and cadmium simultaneously decline with increasing of electrolysis time and weight percent of cadmium or with decreasing the weight percent of copper. Current efficiency was higher at the initial stage of electrolysis for all weight percents of metals. The results showed that the decay of copper concentration was exponential at all weight percents of copper, confirming that the electrodeposition of copper is under mass transfer control in the presence of cadmium. While the decay of cadmium concentration was linear at lower weight percent of cadmium then changed to an exponential behavior at high weight percent of cadmium in the presence of copper.