• 한국가구학회지
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• 제24권3호
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• pp.273-285
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• 2013

The bent wood technique has been used for making the bow, the musical instruments and the wagon wheel, The Winsor chair of England in 1730's was the first Lfurniture product by using this method. This method was spread out by Michael Thonet in Austria after the Industrial Evolution. Early making technique of Winsor chair was relatively easy, but Michael Thonet's bent chair was mass produced by the machine and launched the revolution in the industrial furniture. 20th-Century European furniture designers applied the method of layering and forming plywood to bent chairs, enhanced the function and conformability. The bent chair had a big impact on modern chair design. The bent chair has the formative beauty and convenience from the character of softness and colors of wooden materials and has been developed variously by furniture designers. This study is a new approach to use Dyed-Gathered Wood with various colors and patterns as a material of the bend wood. First, bent wood with the Dyed-Gathered Wood enhances a close texture of wooden material textures instead of coating the surface. Second, flexibility of the bent wood with the Dyed-Gathered Wood enables wood bending techniques. Lastly, the Dyed-Gathered Wood is made with relatively cheap woods, replaces expensive imported woods which cause product price rise. This method enables a material cost saving and a stable supply of material.

• 대한금속재료학회지
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• 제49권6호
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• pp.454-461
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• 2011

In this study, the relationship between corrosion resistance and microstructural characteristics such as grain size reduction, preferred orientation, and homogenous distribution of elements and impurity by mechanical milling of magnesium powder was investigated. Mechanical milling of pure magnesium powder exhibited a complex path to grain refinement and growth together with preferred orientation reversal with milling time. It was also found that anisotropic formation of dislocation on the basal plane of magnesium was initially the dominant mechanism for grain size reduction. After 60 hrs of milling, grain coarsening was observed and interpreted as a result of the strain relaxation process through recrystallization. In spite of the finer grain size and strong (002) texture developed in the sample prepared by spark plasma sintering at $500^{\circ}C$ for 5 min after mechanical milling for 2hrs, the sample showed a higher corrosion rate. The results from this study will be helpful for better understanding of the controlling factor for corrosion resistance and behaviors of mechanical milled magnesium powders.

• 한국분말재료학회지
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• 제29권1호
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• pp.28-33
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• 2022

Aluminum-based powders have attracted attention as key materials for 3D printing owing to their low density, high specific strength, high corrosion resistance, and formability. This study describes the effects of TiC addition on the microstructure of the A6013 alloy. The alloy powder was successfully prepared by gas atomization and further densified using an extrusion process. We have carried out energy dispersive X-ray spectrometry (EDS) and electron backscatter diffraction (EBSD) using scanning electron microscopy (SEM) in order to investigate the effect of TiC addition on the microstructure and texture evolution of the A6013 alloy. The atomized A6013-xTiC alloy powder is fine and spherical, with an initial powder size distribution of approximately 73 ㎛ which decreases to 12.5, 13.9, 10.8, and 10.0 ㎛ with increments in the amount of TiC.

• 한국초전도ㆍ저온공학회논문지
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• 제8권4호
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• pp.12-14
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• 2006

YBCO coated conductors have been fabricated by the reel-to-reel processing using TFA-MOD method. In this work, the fluorine-free Y & Cu precursor solution was synthesized to shorten the calcining time by reducing the evolution of HF gas, thus the meter-long YBCO precursor films can be made within few hours by the continuous slot-die coating & calcination step using the F-free Y & Cu precursor solution. The annealing step was followed to make the YBCO films by the reel-to-reel method with the vertical gas flow system onto the moving tape. To increase the growth rate of the YBCO films by enhancing the removal of HF gas, the low total pressure was adopted in the annealing processing. And the water partial pressure and the oxygen partial pressure were varied to optimize the growth conditions of the MOD-YBCO films on the buffered metal tape. FE-SEM and XRD were used to investigate the surface morphologies and the texture of the meter-long YBCO films. The end-to-end critical current $(I_c)$ of 63A/cm-width and the critical current density $(J_c)$of $0.9MA/cm^2$ with the thickness of $0.7{\mu}m$ were obtained in the 0.42m long coated conductor.

• Progress in Superconductivity
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• 제3권2호
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• pp.198-212
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• 2002

The effects of reacted precursors on phase evolution, microstructure, $J_{c}$ and junctional characteristic of the inter-granular contacts were investigated in Ag-sheathed T1-1223 tapes prepared using three kinds of reacted precursors, and compared to those in the tape prepared using an unreacted precursor The precursors were prepared by heat-treating a mixture of Sr-Ba-Ca-Cu-O, $Tl_2$$O_3$, PbO and $Bi_2$$O_3$ powders at $805^{\circ}C$ (precursor I ), $840^{\circ}C$ (precursor II ) and $905^{\circ}C$(precursor III) for 20 min. Tl-1223 phase content, grain size and J\ulcorner in the tapes appeared to increase in an order of precursors I, II and III Compared to tapes prepared using an unreacted precursor, the tapes prewar ed using precursors II and III revealed reduced pore and impurity densities and an enhanced texture. Also characteristic of inter -granular contacts and fraction of strong-links were improved. The improved properties are attributed to enhanced densification resulting from using the reacted precursors.s.

• 대한기계학회논문집A
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• 제38권7호
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• pp.743-749
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• 2014

본 연구에서는 고강도-고연성 펄라이트 강선을 제조하기 위하여 비원형 신선 공정을 적용하였다. 다단 비원형 신선 공정을 A와 B로 정의한 2 종류의 가공경로를 이용하여 상온에서 12 패스까지 수행하였다. 비원형 신선 공정과의 비교를 위해서 기존의 원형 신선 공정을 수행하고 기계적 특성과 집합조직 발달에 대해 비교를 수행하였다. 원형 신선 공정으로 제조된 강선은 10 패스에서부터 박리파괴가 관찰되었지만, 비원형 신선 가공경로 B의 경우는 12 패스에서도 박리파괴가 발생하지 않았으며, 이는 X-선회절로부터 측정된 집합조직 결과에서 원형집합조직의 발달이 적은 것과 연관된다. 따라서, 다단 비원형 신선 공정을 통하여 기존의 신선 공정보다 박리파괴의 발생 가능성을 저감시킴으로써 높은 비틀림 연성을 갖는 고강도 펄라이트 강선을 제조할 수 있음을 확인할 수 있었다.

• 보존과학회지
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• 제25권3호
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• pp.255-271
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• 2009

이 연구는 기흥 농서리 유적에서 출토된 신석기, 청동기 및 원삼국 시대의 토기를 대상으로 산출상태와 물리적, 광물학적 및 지구화학적 특성을 분석한 것이다. 이 결과, 신석기시대 토기편은 사질 태토와 다량의 활석 및 운모 비짐이 특징적이며, 청동기시대 토기편은 특별한 정선과정 없이 사질의 태토를 사용한 것으로 나타났다. 또한 원삼국시대 토기편은 정선된 태토를 이용하였으며, 각 시대별 토기편은 점이적으로 변화되는 경향이 나타난다. 또한 화학조성을 비교한 결과, 유적지 주변의 동일 기반암에서 풍화에 의해 생성된 원료를 이용하여 제작된 것으로 해석되었다. 그러나 신석기시대 토기는 다량의 활석과 운모 등을 첨가하였고, 원삼국시대 토기편은 태토를 매우 정선하여 이용하는 등 제작기법에서 시대에 따른 차이를 보인다. 이들 토기편의 소성온도는 신석기시대의 경우, 대부분 $700{\sim}760^{\circ}C$, 청동기시대의 경우는 $850{\sim}900^{\circ}C$ 그리고 원삼국시대는 $900{\sim}1,050^{\circ}C$로 전체적으로 넓은 소성범위를 갖는 것으로 나타났다. 그러나 각 시대별 토기의 특징은 시간적으로 단절된 특징을 보이지 않으며 제작기법 상의 변화양상이 나타난다.

• Animal Bioscience
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• 제35권7호
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• pp.1069-1079
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• 2022

Objective: The objective of this study was to investigate the effect of 4-month intensive feeding on the meat quality, fatty acid profile, flavor, and growth performance of grazing Hulunbuir sheep (HBS). Methods: The HBS were selected 4-months after birth in a pasture rearing system as the experimental animals (n = 44, female, average body weight 23.8±2.2 kg) then divided equally into pasture-based grazing fattening (PAS) and concentrate-included intensive fattening (CON) groups for another 4-month finishing. When finished fattening, all animals were slaughtered to collect musculus longissimus dorsi subcutaneous adipose tissue and to investigate the influences on meat quality, fatty acid profile, flavor and growth performance. Results: The results showed lambs in CON group got significantly higher live weight, hot carcass weight, and dressing percentage. The CON group had significantly higher value of redness (a^*), lightness (L^*) and water holding capacity (p<0.05), significantly lower value of Warner-Bratzler shear force than the PAS group (p<0.05). The subcutaneous fat from CON group lambs demonstrated a significantly higher content of C18:1 and C18:2 (p<0.05), but lower C14:0 and C16:0, indicating an increased degree of unsaturated fatty acid. The content of 4-methyloctanoic acid, 4-ethyloctanoic acid and 4-methylnonanoic acid had increased 2 to 4 times, representing a more intense odor in the CON group. However, the values were still lower than most sheep breeds reported, indicating the indoor feeding system could not fundamentally deteriorate the excellent meat characteristic of HBS. Conclusion: It was evident that lambs in CON group exhibited a better meat production performance, improved in meat color, texture and healthier fatty acid profile through pasture-weaned concentrate included intensive fattening system, which offers a good alternative regimen for lamb finishing and has a wide prospection in the HBS meat industry.

• 복식
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• 제50권
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• pp.129-144
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• 2000

In the history of the costume of Western Europe one of the most interesting apects is that the silhouette of women's dress has been continuously evolved. There can be various origins in this changing silhouette but the most important origin is that clothes of any period are the reflection of the architectural political religious and economic background against which they are worn they must also be djusted to the texture and design of the materials produced at the time and of course there is always the basic instinct of sex attraction. The changing line in men's and women's clothes has been demanded by each period but man's great active life did not required the development of exaggerated line which could restrict his movements. Exaggeration in men's clothes has usually been confined to accessories only details could be simplified or abandoned altogether in time of action. However Woman has no great concern in these restrivtions and when an era demanded an exaggerated silhouette she developed it to the utmost limit with out any hesitation plunged herself into whalebone cane and steel for the desired line and then later to adapt herself to a changing world just as without any hesitaion abandoned all these artificial props. In this study first of all the origin of the corset and the evolution of silhouette will be chronologically studied and rearranged on the basis of written materials such as text books theses and catalogs which are related to corset In this section the most important backgrounds-social religious and economic-which caused the chages of silhouette will be scrutinized in a time order. Then the shapes and functions of corsets will be looked into in a more detailed way. In addition the materials and decorations which were preferred to achieve the desired silhouette will be examined. Finally underwear which was and has been worn for cleanness protection the shapes of outer clothes and erotic mood will be studied.

• 자원환경지질
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• 제26권3호
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• pp.349-361
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• 1993

The granitic rocks in the study area are divided into the schist and gneiss complex, Yongdok pluton, Yonghae pluton and Onjong pluton by their texture, fabric and relationship to the adjacent rocks in the field, Schist and gneiss complex occurs as xenolith or roof pendant in the Yongdok, Yonghae and Onjong plutons. The Yongdok pluton occurs in association with pegmatite and aplite in many places of its pluton. In the field it is obviously clarified that the Yongdok pluton is unconformably overlay by the Cretaceous sedimentary rocks. The Yonghae and Onjong plutons are gradationally changed each other, and these plutons truncate both the Yongdok pluton and the Cretaceous sedimentary rocks. Petrographically, the Yongdok pluton consists of granodiorite and granite with minor quartz monzonite. The Yonghae pluton is composed of diorite, quartz diorite, tonalite, and granodiorite. The Onjong pluton also ranges granodiorite to granite. Both the Yongdok and Yonghae-Onjong plutons are different in the constituent minerals, such as alkali feld~par, myrmekite, mica, sphene and mafic minerals. This suggests that each pluton might have been different crystallization sequence and characteristically different gological history during the crystallization period. Iron/magnesium ratio in biotite and hornblende from both the Yongdok and Yonghae-Onjong plutons gradually decrease as the differentiation index increasing in the whole rock. The decrease of this ratio strongly depend on the increase of opaque mineral contents. From the results of chemistry in the whole rocks and some mafic minerals, it is suggest that the granite plutons of the two different geological ages would have been suffered the environment of high oxygen fugacity in the process of magmatic emplacement and during the crystallization period.