• 소성∙가공
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• 제21권8호
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• pp.506-511
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• 2012

Aluminum brazing normally requires a careful control of temperature due to the small interval between brazing and melting temperatures for base materials. Unsuitable processing conditions, including brazing temperature outside admissible range, gap between brazed materials or inadequate flux feeding, can lead to joining defects. In this study, A357 was used as a filler metal for the brazing of pure aluminum base materials and brazed at temperatures in the semi-solid state. Interface microstructures with base materials were observed using optical metallography(OM) and scanning electron microcopy(SEM) with energy dispersive spectroscopy(EDS), and compared to conventional aluminum brazing.

• 약학회지
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• 제8권3호
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• pp.76-79
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• 1964

The metabolism of p-methoxycinnamic acid (p-MCA) has been studied in man and rabbits. Possible compounds were examined for metabolites by crystalization and by paper chromatography, which excreted after adminstration of p-MCA by stomach tube and intravenous injection. p-Methoxyhippuric acid was isolated from urine. Although pure glucuronide was not crystallized from urine, product was obtained by basic lead salt method, which gave p-methodxybenzoic acid (p-MBA) on hydrolysis and gave an intese naphthoresorcinol reaction. No evidence for the demethylation of p-MCA was found. These results are indicating that p-MCA may be mainly converted to p-MBA by ${\betha}$-oxidationand excreted as its conjugates with glycine and glucuronic acid. Its oxidation does not appear to be dependent on intestinal micro-organisms.

• 한국표면공학회지
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• 제35권1호
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• pp.11-16
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• 2002

As environmental concerns increasing, the electronics industry is focusing more attention on lead free solder alternatives. In this research, we have researched wettability of intermediate solder of Sn3Ag9Bi5In, which include In and Bi and has similar melting temperature to Sn37Pb eutectic solder. We investigated the wetting property of Sn3Ag9Bi5In. To estimate wettability of Sn3Ag9Bi5In solder on various substrates, the wettability of Sn3Ag9Bi5In solder on high-pure Cu-coupon was measured. Cu-coupon that plated Sn, Ni and Au/Ni and Si-wafer adsorbed Ni/Cu under bump metallurgy on one side. As a result, the wetting property of Sn3Ag9Bi5In solder is a little better than that of Sn37Pb and Sn3.5Ag.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집B
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• pp.361-365
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• 2001

Laboratory tests are conducted to validate the mechanical model of a filament-wound composite shaft. Also, design charts are produced by validated analytical calculations based on the Timoshenko beam model of a layered steel/composite structure. The major results found are that steel/composite hybrid shafts can lead to better dynamic and static performances over steel or pure composite shafts of the same volume, and the most effective composite structures contain some steel in the form of a tubular core. These results can be used in the design process of composite boring bars and automotive drive shafts.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2008년도 춘계학술대회 논문집
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• pp.485-487
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• 2008

Aluminum brazing needs normally careful control of temperatures due to little difference between brazing temperatures and melting temperatures of base materials. Unsuitable processing conditions such as brazing temperature, gap between brazed materials, inadequate feeding of flux, etc. can lead to occur joining defects. In this study, A357 was used as a filler metal for the brazing of pure aluminum base materials. A357 was brazed at temperatures in the semi-solid state. Interface microstructures with base materials were observed using OM and SEM/EDS and compared to conventional aluminum brazing.

• 한국결정성장학회지
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• 제10권6호
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• pp.418-424
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• 2000

sol-gel 방법으로 순수한 $TiO_2$와 Pb가 10 mol % 첨가된 $TiO_2(Pb_xTi_{1-x}O_2$(x = 0.1)) 분말과 박막을 제조하였다. $TiO_2$제조에는 titanium isopropoxide와 ethanol이 $Pb_xT_{1-x}O_2$(x = 0.1) 제조에는 lead acetate trihydrate와 titanium triisopropoxide monoacethylacetonate이 사용되었다. P-type Si(100) wafer, ITO glass 기판 위에 sol-gel spin-coating방법으로 박막을 형성시켰으며 상(phase)의 형성과 결정화를 위해서 400~$800^{\circ}C$에서 열처리하였다 준비된 분말 및 박막의 특성은 TGA/DTA, XRD, SEM, UV-visible spectrometer를 이용하여 검토하였다. XBD 측정 결과 A(101)면으로 우선 배향된 다결정성 anatase 형의 분말 및 박막을 얻을 수 있었고 Pb가 첨가된 박막에 대한 d-값의 작은 변화가 관측되었는데 이는 Pb가 $TiO_2$살창으로 들어왔음을 의미한다. UV-visible투과 스펙트럼측정 결과에 의하면 Pb가 첨가된 박막에서 투과 스펙트럼의 흡수파장이 장파장쪽으로 이동하는데 이는 Pb가 첨가되면 밴드 갭의 축소가 일어남을 의미한다.

• 펄프종이기술
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• 제45권3호
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• pp.59-68
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• 2013

The cotton contains various impurities such as protein, wax, pectins, coloring matter, even though cotton has been a major source of pure cellulose. The purification processes have been commonly applied to obtain the pure cellulose. However the excessive purification treatments could lead to the damage in the cellulose structure which could result in the degradation of cellulose and the limited application of cotton cellulose. In this study, the changes in cellulose structural properties such as crystallinity and DP(degree of polymerization) by the various conditions of the purification processes were investigated. The less toxic agents such as hydrogen peroxide and sodium silicate were applied for the purification treatment in this study. The increase in the process times, the temperature and the applied amount of chemical agents resulted in the more purified cellulose. The DP of cotton cellulose was increased at the first weak conditions by the reduction of small molecules such as pectin, wax, and so on. Especially the 2 % addition amount of $H_2O_2$ with $Na_2SiO_3$ resulted in the higher value in the DP and the brightness compared to the 1.5 % addition amount of $H_2O_2$. However, the 4 % addition amount of $H_2O_2$ with $Na_2SiO_3$ showed the decreased value because of excessive treatment. In case of the changes in the crystallinity (Gjk), the highest value of the crystallinity was obtained by the 2% addition amount of $H_2O_2$ on the cotton cellulose, which showed similar with the change in the DP.

• 한국콘텐츠학회논문지
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• 제18권8호
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• pp.82-91
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• 2018

본 논문은 들뢰즈의 영화미학, 메를로-퐁티의 현상학적 관점에서 고다르 <카르멘이라는 이름>의 사운드를 고찰하고 있다. 현악 사중주의 리허설 장면은 음악 자신을 비추는 거울 이미지로서, 주 내러티브와의 단절 속에 현재와 과거의 식별 불가능성을 갖는 결정체-이미지가 된다. 한편, 도시 소음과 파도는 순수 시지각적(음향적) 이미지로 구성된 배아로서, 소리의 병치와 대체, 그리고 지향적 연결을 통해 보이는 것과 충돌하는 순수 음향적 결정체로 성장하게 된다. 그러나 이러한 음향적 모순들도 메를로-퐁티의 변증법적 사유를 통해 '단일 운동'으로서의 통합된 소리 범주로 나아가게 되며, 팝음악과 고전음악의 변증법적 사운드 운용조차도 더 이상 장르적 대립이 아닌 소리라는 질료적 범주로 통합된다. 본 연구는 고다르 영화의 사운드 미학을 철학적 사유를 통해 풀어나감으로써 기존연구와 차별화하고 있다.

• 복식
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• 제24권
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• pp.143-155
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• 1995

Unlike pure art such as painting and sculpture, dressmaking , a field of special plastic art, is characterized by its physical and functional nature. Having an inseparable relation with form, it is a field of art expressiion the human innersense of beauty in correlation with other various fields of art. In this respect, I think it should be necessary for us to study the forms of art from the past in order to study the forms of art from the past in order to study the correlations and mutual influencies between forms of pure art and dressmaking and to understand modern dressmaking from the standpoint of art. In this context, this study is an attempt to analze how the form and characteristics of OP ART , which represents the trends of the 1960's is embodied in modern dresses. The results are as follows : Fist , the expression of OP ART in dresses have visual effects harmonizing with bodily movements and , also, expanded the range and dynamics of expression which resulted from the introduction of visual phenomena in a fresh new sense by not limiting itself to the suggestion of patterns of OP ART. Second, OP ART paintings expressed the mobility and rhythimicity of a body in a limited space in a two-dimensional plane way of expression . When a dress is worn, however, it expands such mobility and rhythmicity in a cubic , three-dimensional way, maximizing the effects of , and boldly expression, OP ART, it can also create a new silhuette and ability of formation by seeking an open expression of OP ART rather than an expression of OP ART it self , due to the infinite possibility and unpredictability by the dynamics of movements and the elements principle of designs. Third , by applying the patterns of OP ART to dresses, we can obtain special visual effects of design, cover up the body's weak points, and create a desired three -dimensional sense by highlighting the beauty of the body's curved lines. Although modern dresses and OP ART are different genres of art, both have something in common in their pusuits. Since there is a infinite possibility in OP ART, there should be continuous attempts to combine dresses and art satisfying the sense of the times, which will lead dressmaking to a higher-dimensional dressmaking plastic art.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.371-372
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• 2012

We have studied lead-based gapless semiconductors, $PbPdO_2$, which is very sensitive to external parameters such as temperature, pressure, electric field, etc[1]. We have fabricated pure $PbPdO_2$, Co- and Mn-doped $PbPdO_2$ thin films using the pulsed laser deposition. Because of the volatile element of Pb, it is very difficult to grow the films. Note that in case of $MgB_2$, Mg is also volatile element. So in order to enhance the quality of $MgB_2$, some experiments are carried out in annealing with Mg-rich atmosphere [2]. This annealing process with volatile element plays an important role in making smooth surface. Thus, we applied such process to our studies of $PbPdO_2$ thin films. As a result, we found the optimal condition of ex-situ annealing temperature ${\sim}650^{\circ}C$ and time ~12 hrs. The ex-situ annealing brought the extreme change of surface morphology of thin films. After ex-situ annealing with PbO-rich atmosphere, the grain size of thin film was almost 100 times enlarged for all the thin films and also the PbO impurity phase was smeared out. And from X-ray diffraction measurements, we determined highly crystallized phases after annealing. So, we measured electrical and magnetic properties. Because of reduced grain boundary, the resistivity of ex-situ annealed samples changed smaller than no ex-situ sample. And the carrier densities of thin films were decreased with ex-situ annealing time. In this case, oxygen vacancies were removed by ex-situ annealing. Furthermore, we will discuss the transport and magnetic properties in pure $PbPdO_2$, Co- and Mn-doped $PbPdO_2$ thin films in detail.