• Proceedings of the Korean Society For Composite Materials Conference
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• 2003.10a
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• pp.46-49
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• 2003

Cu have been widely used as signal transmission materials for electrical electronic components owing to its high electrical conductivity. However, it's size have been limited to small ones due to its poor mechanical properties, Until now, strengthening of the copper at toy was obtained either by the solid solution and precipitation hardening by adding alloy elements or the work hardening by deformation process. Adding the at toy elements lead to reduction of electrical conductivity. In this aspect, if carbon nanofiber is used as reinforcement which have outstanding mechanical strength and electric conductivity, it is possible to develope Cu matrix nanocomposite having almost no loss of electric conductivity. It is expected to be innovative in electric conduct ing material market. The unidirectional alignment of carbon nanofiber is the most challenging task developing the copper matrix composites of high strength and electric conductivity In this study, the unidirectional alignment of carbon nanofibers which is used reinforced material are controlled by drawing process in order to manufacture the intermediary materials for the carbon nanofiber reinforced Cu matrix nanocomposite and align mechanism as well as optimized drawing process parameters are verified via experiments and numerical analysis. The materials used in this study were pure copper and the nanofibers of 150nm in diameter and of $10~20\mu\textrm{m}$ In length. The materials have been tested and the tensile strength was 75MPa with the elongation of 44% for the copper it is assumed that carbon nanofiber behave like porous elasto-plastic materials. Compaction test was conducted to obtain constitutive properties of carbon nanofiber. Optimal parameter for drawing process was obtained by experiments and numerical analysis considering the various drawing angles, reduction areas, friction coefficient, etc Lower reduction areas provides the less rupture of cu tube is not iced during the drawing process. Optimal die angle was between 5 degree and 12 degree. Relative density of carbon nanofiber embedded in the copper tube is higher as drawing diameter decrease and compressive residual stress is occurred in the copper tube. Carbon nanofibers are moved to the reverse drawing direct ion via shear force caused by deformation of the copper tube and alined to the drawing direction.

• Restorative Dentistry and Endodontics
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• v.20 no.1
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• pp.129-141
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• 1995

Composite resin and glass-ionomer cement can be used for the purpose of repair of defective amalgam restoration. The purpose of this study was to evaluate of shear bond strength of esthetic restorative materials to dental amalgam. The materials used in this study were Photo Clearfil Bright(light curing composite resin), Clearfil F II(chemical curing composite resin), Fuji II LC(light curing glass-ionomer cement), Fuji II (chemical curing glass-ionomer cement), All-Bond 2(intermediary), and Scotchbond Multi-Purpose (intermediary). A total of 120 acrylic cylinders with amalgam were divided into 8 groups After amalgam condensation, all specimens were stored for 48 hours in water at $37^{\circ}C$ and tested with Instron universal testing machine between amalgam and composite resins and glass-ionomer cements. The data were analyzes statiscally by ANOVA and Duncan test. The following results obtained ; 1. The shear bond strength of bonded composite resin to amalgam was higher than bonded glass-ionomer cement(P<.001). 2. The group 4 had highest shear bond strength with 15.45kgf/$cm^2$ and the group 5 had lowest shear bond strenght with 3.26kgf/$cm^2$(P<.001). 3. In the group 3, 4, 5, 6, the group 3, 4 with All-Bond 2 had higher shear bond strength than the group 5, 6 with Scotch bond MP both in light-curing and in chemical curing. 4. Both in composite resin and glass-ionomer cement, chemical curing materials had higher shear bond stength than light curing materials(P<.001).

• Korean Journal of Materials Research
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• v.1 no.2
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• pp.71-76
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• 1991

The superconducting powders in $YBa_2Cu_3O_{7-x}$ and Bi-Pb-Sr-Ca-Cu-O system were easily prepared from water in oil type emulsion by loading each cation into the aqueous phase. In $YBa_2Cu_3O_{7-x}$ system, the superconducting orthorhombic phase was formed by calcining at $750^{\circ}C$ for 10h in $O_2$. The size of the superconducting phase powders was submicron. The density of the sintered specimen using this powders was about 95% of the theoretical density and the resistance sharply decreases at about 90K, In Bi-Pb-Sr-Ca-Cu-O system the low Tc phase($(Bi, Pb)_2Sr_2Ca_1Cu_2O_y$) was formed by calcining at $800^{\circ}C$ for 10h in a low oxygen partial pressure of 1/20 atm The shape of clacined powder is thin plate of which size is about $2\mu\textrm{m}$ and thickness is smaller than $\mu\textrm{m}$. It was observed that the high Tc phase ($(Bi, Pb)_2Sr_2Ca_2Cu_3O_y$) was formed by sintering at $850^{\circ}C$ for 30h in oxygen pressure of 1/20 atm without intermediary grinding. The above sintered sample exhibited superconductivity with a Tc(zero)=105K.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.6 no.1
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• pp.57-64
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• 2003

This study aims to discuss the characteristics on marketing distribution of landscape materials after consideration in the side of cognition on the present condition of marketing which is important factors for analysis in understanding the market of landscape materials. To do this, the investigation of marketing distribution are to collect data refer to purchases and sales reports and questionnaires, these results are used to analyzed the operative factor of forming market structure and problematic, improvement spot of marketing distribution. The periodic range of this paper is limited on 609 landscape materials and examination was performed from 21.Feb. to 15.Mar, in 2002. The results of the whole prices trends and marketing distribution survey can be summarized as follows : 1. Differences of cognition on marketing distribution among four group toward problematic spot on product and marketing of landscape materials was summarized as follows : 1) Group of landscape design : Interest of government, Various articles. 2) Group of landscape construction : Communication of marketing information, Role of intermediary ecc. 3) Group of landscape materials and cooperation between company and university : Interest of government ecc, 2. Differences of cognition on marketing distribution among four group toward improvemental spot on product and marketing of landscape materials was summarized as follows : 1) Group of landscape design and construction : Network of marketing distribution on landscape materials, Criterion of articles, Quality adiministration through establishment of sale level ecc.. 2) Group of landscape materials : Employment of specialist education program ecc.. 3) Group of cooperation between company and university : Conscious reformation of comsumer ecc.

• Polymer(Korea)
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• v.33 no.2
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• pp.124-130
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• 2009

In presence of a polymer, the crystallization of low MW organic materials can be stopped at an intermediary step, where mesocrystals can be identified. A mesocrystal is defined as a superstructure of nanoparticles having polymer-adsorbed crystal faces on the scale of several hundred nanometers to micrometers. This study examined the effects of water soluble polymers and relevant parameters on the formation of guanosine-5'-monophosphate mesocrystals. It was observed in OM and SEM that GMP obtained in a polymer solution had a unique particle morphology different from the typical one of GMP. XRD analysis indicated that the polymer-directed crystallized GMP had a different polymorph of GMP. This result shows that the crystal structure of GMP can be changed by polymers. It was observed in TGA analysis that the polymer-directed crystallized GMP had a different water content, indicating a different type of hydrate.

• Journal of the Korea Furniture Society
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• v.23 no.2
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• pp.103-109
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• 2012

King Muryeong reungeseo Foot-rest on the subject of the king excavated a USB memory design. Foot-rest of the form and the meaning of patterns were expressed on a USB memory. Minds of ordinary people in these times communicator acts as an intermediary in the sky to give a sense of the king, such as Foot-rest patterns carved on the engraved turtle. Closely related to modern life, as cultural products associated with the computer by connecting supplies of products for some tourists, not only about reaching the wider public should focus on development. Meanwhile, the USB memory could not be seen in the case of natural wood material by using the age and the individual tastes of consumers represents USB memory into the merit of portability, necklaces pendants items for restoration, phone strap, key chain, etc. By combining the functionality increases. Meanwhile, on the basis of a practical item, the largest issue was the consumption of cultural products by maximizing the economic benefit of the community and at the same time a symbol of cultural heritage items have been transformed into the effectiveness of the national image enhancement is expected to be achieved.

• Journal of the Korean Society of Costume
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• v.59 no.1
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• pp.29-46
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• 2009

Aiming at finding symbolistic meanings and characteristics of makeup in Chinese Beijing Opera("BO"), this study formulated a theoretical framework mainly from literature in the Symbolism and symbolistically analyzed materials related to BO makeup from literature, internet web pages and illustrated news concerning performing arts. Main objects to analyze are the characteristics of four main roles in BO and the patterns, symbols, ornaments and traditions of Beijing Opera facial makeup("BOFM"). Four main roles are Sheng, Tan, Ching and Chou, categorized by gender, age, social position and personality. The result to analyze symbolistic meanings and characteristics of makeups for the roles in BO are as follows: the patterns and colors of BOFM function as explanations to help audiences understand each role's personality and dramatic situations as well as provide hints about the development and ending of an opera: that is, BO makeup is a communicative intermediary between audiences and actors in BO. It tends to follow the stereotypes, which conventionally dress and exaggerate the characters of roles, and copy the traditional Chinese perception about colors. Thus, by the metaphysical and typical expression of BOFM, Chinese people have not been pursuing the realism in opera but applying BO makeup to a mutual communication method between audiences and performing artists as to share their collective cultural heritages and spirits. Threfore, BO makeup has been an interacting language between the two entities and grown within the history of BO as a beauty art to highlight a BO by its unique systems, ornaments and beauty.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.240-241
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• 2007

In general, high temperature superconducting coated conductors have intermediary buffers layer consisting of seed, diffusion barrier and cap layers. Simplification of the oxide materials buffer architecture in the fabrication of high temperature superconducting coated conductors is required because the deposition of multi-layers buffer architecture leads to a longer manufacturing time and a higher cost process of coated conductors. Thus, single buffer layer deposition seems to be important for practical coated conductor manufacturing process. In this study, a single gradient layered buffer deposition process of YZO for low cost coated conductors has been tried using DC reactive sputtering technique. About several thick YZO gradient single buffer layers deposited by DC co-sputtering process were found to act as a diffusion layer.

• Korean Journal of Plant Resources
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• v.4 no.2
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• pp.67-74
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• 1991

Many people have a growing interest on the health result from economic improvement, various environimental pollution and stress, and unrest on the adult diseases etc.In these result, demand for the herb medicine continues to expand. Farmers of theour country have a hardship in the farm management owing to of opening and liberaliza-tion, and make strenuous efforts on the devclopment of substitute crops to overcomethese differties. Government nowadays recommends the cultivation of the economiccrops like a flowers, medicinal herbs mushroom and clean vegetables. Medicinal herbsare specially profitable among these crops because herbs are possible to culture inwaste land, disused field and slope land, and owing to need less labor and competitionthan those of other crops. The most important problem is the facts that the compli-cation of currency structure of herb medicine inflicts mucll loss to cultivators. Therefore, this study was investigated the state of herb cultivation and the facts to be imploved in currency structure of the harvested herb medicine.1 . The cultivating area and output have been gradually increased and much produc-ted in Kyoungbuk, Kangwon, Choongbuk, Cheonbuk and Cheonnam province in or-der of cultivating area 2. Collection amount of wild herb medicine is decreasig bythe reason of the varous difficulties on the collection. 3. Cultivators of medicinal herbscan make agricultural management more resonable in information exchange on theherb cultivation, purchase of seed, fertilizer, chemicals and other materials, and sell-ing of harvested herb medicine by organization of cultivator fraternity. 4 Cultivatorshave to exclude intermediary margin by the development of direct transaction andcontract cultivation with medicinal herb store, drug manufacturer, chinese meicinehospital and trading firm etc. And also, by the performing exportation with foreign consumer.

• Korean Journal of Plant Resources
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• v.28 no.6
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• pp.697-703
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• 2015

Twenty apple germplasm accessions from the Korean Genebank were successfully cryopreserved using two-step freezing to back up genetic resources maintained by field collections. This study examined the morphological and genetic stability of cryopreserved dormant apple buds that were stored in liquid nitrogen, and then rewarmed and regrown. Whole plants were regenerated directly from dormant buds through budding without an intermediary callus phase. The cryopreserved buds produced high levels of shoot formation (76.2-100%), similar to those of noncryopreserved buds (91.3-100%), with no observed differences between cryopreserved and noncryopreserved materials. Three of the twenty cryopreserved apple germplasm accessions were used to assess morphological and genetic stability. No differences in morphological characteristics including shoot length, leaf shape, leaf width/length ratio, and root length were observed between controls (fresh control and noncryopreserved) and cryopreserved plantlets. The genetic stability of regenerants (before and after cryopreservation) was investigated using inter simple sequence repeat (ISSR) markers. The ISSR markers produced 253 bands using four primers, ISSR 810, SSR 835, ISSR 864, and ISSR 899. These markers showed monomorphic banding patterns and revealed no polymorphism between the mother plant and regenerants before and after cryopreservation, suggesting that cryopreservation using two-step freezing does not affect the genetic stability of apple germplasm. These results show that two-step freezing cryopreservation is a practical method for long-term storage of apple germplasms.