• The Korean Journal of Ceramics
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• 제4권2호
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• pp.95-98
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• 1998

We have developed new type of superconducting-superionic conducting nanohybrids, $Ag_xI_wBi_2Sr_2Ca_{n-1}Cu_nO_y$ (n=1 and 2) by applying the chimie douce reaction to the superconducting Bi-based cuprates. These nanohybrids can be achieved by the stepwise intercalation whereby the $Ag^+$ ion is thermally diffused into the pre-intercalated iodine sublattice of $IBi_2Sr_2Ca_{n-1}Cu_nO_y$. According to the X-ray diffraction analysis, the Ag-I intercalates are found to have an unique heterostructure in which the superionic conducting Ag-I layer and the superconducting $IBi_2Sr_2Ca_{n-1}Cu_nO_y$ layer are regularly interstratified with a remarkable basal increment of ~7.3$\AA$. The systematic XAS studies demonstrate that the intercalation of Ag-I accompanies the charge transfer between host and guest, giving rise to a change in hole concentration of $CuO_2$ layer and to a slight $T_c$ change. The Ag K-edge EXAFS result reveals that the intercalated Ag-I has a $\beta$-AgI-like local structure with distorted tetrahedral symmetry, suggesting a mobile environment for the intercalated $Ag^+$ ion. In fact, from ac impedance analyses, we have found that the Ag-I intercalates possess a fast ionic conductivity ($\sigma_i=10^{-1.4}\sim 10^{-2.6}\Omega^{-1}\textrm{cm}^{-1}\;at\;270^{\circ}C$ with an uniform activation energy ($\DeltaE_a=0.22\pm 0.02$ eV). More interesting finding is that these intercalates exhibit high electronic conducting as well as ionic ones ($t_i$=0.02~0.60) due to their interstratified structure consisting of superionic conducting and superconducting layers. In this respect, these new intercalates are expected to be useful as an electrode material in various electrochemical devices.

• 한국전통조경학회지
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• 제40권3호
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• pp.46-56
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• 2022

본 연구는 서울특별시 문화재의 입지특성을 분석하여 문화재 유형별 홍수 민감성을 파악하고자 하였다. 홍수 민감성 관련 입지요인으로 고도, 경사, 최소 수계거리, 지형입지를 분석하고, 문화재가 현 지점에 위치하게 된 역사·인문적 입지환경을 문헌고찰하였으며, 연구결과는 다음과 같다. 첫째, 서울특별시 문화재는 특히 한양도성 내에 집중 분포하고 있다. 계량적 공간분석 결과에서도 중구-종로구-은평구 진관동-강북구 우이동을 중심으로 문화재가 밀집하고 있음이 확인되었다. 둘째, 홍수 민감성이 높은 입지특성을 지닌 문화재 유형은 상업·유통, 교통, 근대교통·통신, 지구과학기념물, 주거, 관청, 궁궐로 나타났다. 셋째, 홍수 민감성이 낮은 입지특성을 지닌 유형은 자연명승, 통신, 요업, 불교, 무덤, 능묘조각 문화재로 나타났다. 자연환경의 변화와 더불어 인위적인 영향으로 인해 문화재의 가치를 손상시킬 수 있는 위험 요인들이 점차 증가하는 작금에, 본 연구는 문화재 고유의 특성을 반영한 취약성 분석을 위한 기초자료를 제공한다. 이는 자연적 요인과 더불어 인문·사회과학적 자료를 분석에 함께 포함하여 문화재 관리 및 보호를 위한 좀 더 포괄적이고 종합적인 통찰에 기여할 수 있을 것이다.

• 한국산업경영시스템학회:학술대회논문집
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• 한국산업경영시스템학회 2002년도 춘계학술대회
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• pp.243-257
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• 2002

A study on processing for producing cure seat radiated by Original Infrared Rays and Magnatic force. We are well aware that Original Infrared Rays and Magnatic force influence on our human body benificially. In the technical background of this research product, we treated that the product has some operations of ceramic hardwood charcoal, far infrared rays and magnetic, so it can serve large part curative values made of far infrared rays and magnetic force of ceramics. Also, in the special quality of the product deal with ceramic, hard charcoal, ferrite, gelatin what is needed in production. And among them, ferrite, ceramic and hard charcoal are introduced by the manufacturing process of the moleculeization. In concluding, this study described the manufacturing process on the basis of the worksheets and arranged the useful effect which effect on human body. There are so many symptoms in the pain of muscle. It's very various. for example, it is the cause of the liver, the spleen and a kidney function's weakening. the cause of the backbone subluxation, the cause of the shoulder joint and scapula, the cause of the sacrum and iliacjoint, the cause of hip joint and the cause of a sprain. In this thesis, we mainly deal with the method which the muscle and nervous system disease by fatigue and a sprain cure seat radiated by Original Infrared Rays and Magnatic force. then, Original Infrared Rays and Magnatic force pack up frapezius muscle, gluteus minimum muscle, gluteus medius muscle, gluteus maximus muscle, pririformis muscle around the spine. through this course the moral pressure by the nervous system disease can be treat.

• 대한치과보철학회지
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• 제26권1호
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• pp.51-61
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• 1988

The recently introduced castable glass ceramics incorporate properties characteristic of natural teeth and they are regarded as an ideal material to restore lost tooth structure. The purpose of this study was to compare the marginal fit of castable ceramic crown with that of the metal-ceramic crown in the process of heat treatment. Two master dies for castable ceramic crowns and metal-ceramic crowns were fabricated from being cast with the base metal. Each master die was duplicated with addition silicone and hard stone. Ten castable ceramic crowns were made on each hard stone die and their marginal openings were measured three times first, after casting; second, after ceramming; third, after shading. The other ten metal-ceramic crowns were made on each hard stone die and their marginal openings were measured three times : first, after casting; second, after degassing; third, after porcelain veneering. Each crown was seated on its master die with the constant force delivered by loading jig. And then, marginal openings were measured on four locations by optical projector at X50 magnification. The results were as follows: 1. The mean marginal openings of castable ceramic crowns were $31.1{\pm}12.7{\mu}m$ after casting; $44.6{\pm}12.8{\mu}m$ after ceramming; $51.2{\pm}16.8{\mu}m$ after shading. 2. The mean marginal openings of the metal-ceramic crowns were $26.2{\pm}13.8{\mu}m$ after casting; $29.8{\pm}10.3{\mu}m$ after degassing; $38.0{\pm}14.5{\mu}m$ after porcelain veneering. 3. There was significant increase in the marginal opening of castable ceramic crowns after ceramming, while metal-ceramic crowns sho(wed significant increase after porcelain veneering (p<0.05). 4. Marginal fit of metal-ceramic crown was better than that of castable ceramic crown (p<0.01).

• 청정기술
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• 제17권1호
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• pp.1-12
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• 2011

과학자와 공학자들은 끊임없이 금속, 합금, 고분자, 세라믹 등의 공학재료의 성질을 계속해서 변화하는 사회의 요구에 부응하는 방향으로 개선하여 왔다. 인조 공학재료는 일반적으로 기계적 성질이 우수하여, 자연 재료의 기계적 성질보다 우수한 경우가 많다. 그러나, 이와 같은 공학 재료는 자연계에서 흔히 볼 수 있는 자기 치유능력, 즉 고의적인 인간의 접촉을 거치지 않고도 미세균열을 제거하는 능력이 부족하다. 자연에서 관측할 수 있는 손상관리 패러다임은 여러 가지 종류의 공학재료의 고유성질을 잘 고려하면 인조공학 재료에서도 성공적으로 재현할 수 있다. 특히 적절한 화학반응과 분자간력을 응용하면 고분자, 아이오노머, 복합체와 같은 유기재료에 적용할 수 있는 다양한 자기치유 방법을 개발할 수 있다.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제50권9호
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• pp.427-433
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• 2001

A linear ultrasonic motor was designed by a combination of the first longitudinal and fourth bending mode, and the motor consisted of a straight aluminum alloys bar bonded with a piezoelectric ceramic element as a driving element. That is,$L_1-B_4$ linear ultrasonic motor can be constructed by a multi-mode vibrator of longitudinal and bending modes. Linear ultrasonic motors are based on an elliptical motion on the surface elastic body, such as bar or plates. In general, the natural resonance frequency of the stator is used as a driving frequency of the motor which provides a large elliptical motion. The corresponding eigenmode of one resonance frequency can be excited twice at the same time with a Phase shift of 90 degrees in space and time. And the rotation can be reversed by changing the phase between the two signals from sin$\omega$t to cos$\omega$t. Moreover, the tangential force pushes the slider(rotor) and, therefore, determines the thrust and speed of the motor. The experimental results of fabrication motors, bimorph-tyPe motor showed more excellent than unimorph-type. The maximum speed of TBL-200, TBL-300, TBL-400, TBL -220, TBL-310 and TBL-420 motors were 0.12, 0.37, 0.39, 0.14, 0.55 and $0.60ms6{-1}$, respectively. And the efficiency were reported 1.15, 7.9, 6.6, 2.36, 10.1 and 16.5%, respectively. That time, output thrust of the motor was a strong(1~2N) and the weight of stator was a lightness(5~7g).

• 한국재료학회지
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• 제23권5호
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• pp.286-292
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• 2013

Generally, the color gold has had a biased conception due to its traditional use. Thus, this bias has resulted in a lack of usage of golden glaze on ceramics and also a lack of extensive studies of such glazes. In this paper, optimum conditions and mechanism of formation of gold color crystallization glaze containing $Fe_2O_3$(hematite), which is developed for gold colors of ceramic glazes, were studied. Experimental result showed that there are pyroxene based on diopside and $TiO_2$ phase in the base of a crystallization glaze with a value of $TiO_2$ of 6 wt% confirmed by XRD and Raman Spectroscopy. When $Fe_2O_3$ was used as a colorant for the gold color, the $TiO_2$ peak became extinct and the intensity of the diopside peak was sharper. Feldspar of 60 wt%, talc of 20 wt% and limestone of 20 wt% were used as the starting materials and these were tested using a three component system. The best result of test was selected and extended to its vicinity as an experiment to determine $TiO_2$ and $Fe_2O_3$ contents. The glaze with $TiO_2$ of 6 wt% and $Fe_2O_3$ of 12 wt% addition showed stable pyroxene based diopside crystals and the development of gold color. This gold color was obtained with CIE-$L^*a^*b^*$ values of 51.27, 4.46, 16.15 (a grayish yellow brown color), which was gained using the following firing conditions: temperature increasing speed $5^{\circ}C$/min, holding for 1 h at $1280^{\circ}C$, annealing speed $3^{\circ}C$/min till $1100{\circ}C$, holding for 2 h at $1100{\circ}C$, and finally natural annealing.

• 한국통신학회논문지
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• 제40권5호
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• pp.974-980
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• 2015

해양환경 하에서 강재에 대한 방식 목적으로 Al-3%Mg 용사선재를 이용하여 아크 용사코팅을 실시하였다. 그리고 Al-3%Mg 용사코팅 층의 내식성을 개선하기 위하여 유/무기 복합 세라믹 후처리를 실시하였다. 후처리 적용에 따른 용사코팅 층의 다양한 전기화학적 실험 결과, 양극분극과 음극분극 실험 시 모든 전위구간에서 후처리 적용 시 전류밀도가 작게 나타나 내식성 개선이 확인되었다. 그리고 후처리된 용사코팅 층의 표면에서 관찰된 마이크로 크랙의 영향으로 자연전위 계측 시 심한 전위변동이 나타났으며, 양극분극 실험 시에는 후처리 층의 탈리손상이 용이하게 발생하였다. 그럼에도 불구하고 타펠분석을 기반으로 외부 환경차단 효과를 나타내는 코팅 효율이 92.11%로 산출되어 Al-3%Mg 용사코팅 층의 내식성이 향상되었다.

• 패션비즈니스
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• 제22권1호
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• pp.100-113
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• 2018

From the late 17th to the early 18th century, Europeans were strongly intrigued by products from the East. Therefore, several countries like England, France, and Netherlands formed the 'East India Company' to pursue trade. First, European markets rapidly responded to this desire for exoticism by importing goods; then, they produced imitation Oriental goods. Finally, they made stylistically advanced exotic merchandise from the perspectives of European. In terms of the textile industry, this trend was expressed in the pattern design of silk, or the so called 'bizarre silk.' In this paper, bizarre silk patterns were scrutinized based on a digital archive of museums, catalogues of museums, portal sites, and the literature. The bizarre silk patterns were analyzed then classified into six categories: pseudo-Oriental plant pattern, pattern mingled with architectural motifs, pattern of juxtaposed with Oriental goods, abstract pattern, exuberant pattern with metal threads, and semi-naturalistic pattern. These patterns were characterized according to the following features: strangely large exotic floral patterns were undulating and asymmetrical; exotic foliage and flowers were sometimes mixed with architectural motifs or Oriental goods to easily show the Oriental influence; motifs of bizarre silk patterns were abstractly stylized; bizarre silk patterns became luxurious once more like the Baroque period; finally, floral patterns became more natural, and still exotic motifs remained in the background to maintain the bizarre silk features. These bizarre silk patterns evolved from the viewpoints of Europeans through acceptance stage, compound stage, and confluent stage.

• 공업화학
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• 제22권4호
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• pp.439-443
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• 2011

수산화마그네슘이 첨가된 저밀도 폴리에틸렌-에틸렌 비닐 아세테이트 혼합물의 연소성을 시험하였다. 저밀도 폴리에틸렌-에틸렌 비닐 아세테이트에 수산화마그네슘을 40~80 wt% 첨가하여 용융 혼합하고 성형 후 콘칼로리미터(ISO 5660-1)를 이용하여 그의 연소성을 시험하였다. 수산화마그네슘을 첨가한 시험편은 첨가하지 않은 시험편에 비하여 그의 연소성이 감소하였다. 이것은 순수한 저밀도 폴리에틸렌-에틸렌 비닐 아세테이트에 첨가한 수산화마그네슘의 흡열 분해 때문에 연소 억제성이 향상된 것으로 생각된다. 수산화마그네슘을 첨가한 시험편은 첨가하지 않은 시험편에 비해 낮은 최대열방출률과 낮은 유효연소열을 나타내었고, 수산화마그네슘 함량이 증가할수록 착화시간은 길어지고, 최대열방출률은 감소하였다.