• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 추계학술대회 논문집
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• pp.109-112
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• 1998

SAW filters of transversal type were fabricated on some piezoelectric substrate of the LN 128 $^{\circ}$ Y-X waters through the simulation in which the number of IDT and window function were changed for the required frequency, and the mask making. Their IDT spacing and width were 1.63$\mu\textrm{m}$, 1.239$\mu\textrm{m}$, respectively. Titanium thin films having different thicknesses were introduced between the Al electrode and the substrate for improving the power resistance strength due to its high temperature durability and good adhesion characteristics. All of specimens showed similar insertion loss results, which means the possibility of introducing the Ti layer though it is known to have a higher resistivity leading to a worse insertion loss result. Ti inserted specimens had a better power durability than that of pure Al electrode though their thickness had no effect on the performance.

• Bulletin of the Korean Chemical Society
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• 제34권12호
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• pp.3762-3766
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• 2013

This article examines the modification of surface properties of ultrahigh-molecular-weight polyethylene (UHMWPE) with nanoscale ceramic particles to fabricate an improved composite with butadiene-nitrile rubber (BNR). Adhesion force data showed that ceramic zeolite particles on the surface of UHMWPE modulated the surface state of the polymer and increased its compatibility with BNR. Atomic force microscopy phase images showed that UHMWPE made up the microphase around the zeolite particles and formed the evolving layer with a complex interface. The complex interface resulted in improvements in the mechanical properties of the composite, especially its low-temperature resistance coefficients, thereby improving its performance in low-temperature applications.

• Corrosion Science and Technology
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• 제12권6호
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• pp.295-303
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• 2013

Silane surface treatments have been developed as an alternative for toxic and carcinogenic chromate-based treatments for years. It is consistently observed that ultra-thin films offer excellent corrosion protection as well as paint adhesion to metals. The silane performance is comparable to, or in some cases better than, that of chromate layers. Based on the tetra-ethylorthosilicate(TEOS) and methlyl trieethoxysilane(MTES), inorganic sol was synthesized and formed hybrid networks with $SiO_2$ nano particle and polypropylene glycol(PPG) on Zn alloyed steel surface. According to SST results, addition of 10nm and 50nm $SiO_2$ nanoparticle in synthesized solution improved anti-corrosion property by its shear stress relaxation effect during curing process. Also, SST results were shown that anti-corrosive property was affected by the amounts of organic compounds.

• Korean Chemical Engineering Research
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• 제46권2호
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• pp.397-401
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• 2008

레이저 애블레이션에 의해서 가지상 구조체 형상인 나노입자 응집체를 합성하였다. 기존 마이크론 금속섬유 필터의 표면상에 나노입자 응집체를 고착하여 여과성능을 향상시켰다. 에어로졸 상에서 소결 처리된 나노입자 응집체를 증착한 후 열처리를 하여 나노구조체가 표면상에 형성된 소결 처리된 나노입자 응집체 고착 필터를 제작하였다. 소결 온도가 증가할수록 마이크론 금속섬유 필터 표면상에 고착된 나노입자 응집체의 표면적 증가로 인하여 차압은 조금 증가하지만 여과효율은 현저하게 증가하였다.

• 한국디지털건축인테리어학회논문집
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• 제13권4호
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• pp.61-68
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• 2013

Concrete structure is not the only material vulnerable to physical and chemical processes of deterioration associates with severe conditions. Deterioration of the concrete structure, however, occurs more progressively from the outside of the concrete exposed to severe conditions. Especially, Carbonation, chloride ion attack is more important factor of concrete durability. This study is interested in manufacturing the self-cleaning concrete surface impregnant including TEOS, lithium silicate for the repair of the exposed concrete surface and the color concrete requiring the advanced function in view of the concrete appearance. Form the results, TEOS and lithium silicate are very effective that increasing the concrete durability using self-cleaning concrete impregnant. Self-cleaning concrete impregnant specimens is satisfied with performance requirement of KS standard in adhesion test in tension but the reinforcement of concrete substrate is slight. So, the self-cleaning concrete impregnant of this study is more desirable for the improvement of durability rather than the reinforcement.

• 유공압시스템학회논문집
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• 제7권2호
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• pp.1-6
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• 2010

A new type fiber optic sensing system has been developed as a commercially available standard using the technique of hetero-core spliced fiber optic sensor, for the purposes of monitoring large scaled structures, preserving natural environments and measuring physical phenomenons. The sensing system has been tested and evaluated in a possible outdoor condition in view of the full scaled operation at actual sites to be monitored. Additionally, the developed system in this work conveniently provides us with various options of sensor modules intended to measure such physical quantities as displacement, distortion, pressure, binary states and liquid adhesion. The experiment study has been performed to examine the performance to a pseudo-cracking experiment in the outdoor situation, and to clarify temperature influences to the system in terms of the coupling of optical connectors and the OTDR stability. It has been verified that the sensing system is robust to the temperature change ranging from the general condition to the hard condition. Especially, in this study, the specification and performances of the pressure sensor have been demonstrated to show the capability of inspecting various physical quantities.

• 대한간호학회지
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• 제27권3호
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• pp.477-488
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• 1997

The purpose of this study was to understand the subjective breastfeeding experience of primiparous women to identify how breastfeeding was started and to explore the process of breastfeeding. The Grounded theory methodology was used. Data was collected from 6 primiparous women who had breastfed their infants for at least over 8weeks, recently breastfeeding or having breatfed their infants within the last 6 months. With the permission of the subjects, the interviews were recorded and transcribed. The data were analysed in the framework of grounded theory method as mapped out by Strauss and Corbin(1990). 105 concepts and 21 subcategories were confirmed in the analysis. In the process of data analysis, "Identity as a mother" was found to be the core phenomenon. The 21 sub-categories were as follows : natural food, neighbour inducement, self purpose, good feeling, tenderness, breast pain, change of breast shape, physical discomfort, loss of physical energy, confirmation of maternal role, formation of affection feeling of adhesion, one body through coupling, tie, capacity, role performance, mental comfort, healthy mother, healthy infant, confidence of breast milk, feeling of satisfaction. The sub -categories were again grouped into 14 categories including infant nutritious food, formation of breastfeeding opportunity, feeling of satisfaction, injury of the breast, physical suffering, awareness of mothering, formation of maternal affection, connecting, coupling, acceptance, effort, emotional stability, mother and child health and feeling of achievement.hievement.

• 전기학회논문지P
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• 제65권1호
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• pp.53-56
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• 2016

Because of the low pollution resistance of the porcelain electrical insulator itself, in this work the anti-pollution performance of insulator was improved by using the functional coating. The ceramic substrates that components were same as the porcelain electrical insulator were used in this experiment. The functional films were coated on the ceramic substrate by using a spray coating method, and then the coated substrate were annealed under different coating condition such as natural curing and annealing temperature of $200^{\circ}C$, $300^{\circ}C$ and $400^{\circ}C$. Then, the contact angles of the coated surfaces were measured and the minimum angle ($8.3^{\circ}$) was obtained at $400^{\circ}C$. The anti-contamination properties were measured, revealing that as the contact angle decreased, the anti-contamination properties improved. The hardness and adhesion were small at the natural curing condition however the excellent mechanical properties were obtained under higher temperature annealing.

• 한국구조물진단유지관리공학회 논문집
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• 제8권4호
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• pp.115-122
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• 2004

본 연구에서는 강화보드, 익스팬디드 메탈 그리고, 탄소섬유그리드의 세 가지 보강재와 덮개 콘크리트 대용의 세라믹메탈재를 사용하여 RC보의 인장측을 보강한 경우에 그 보강효과를 파악하기 위한 구조실험을 수행하였다. 구조실험을 통하여 RC보 구조물에서 세라믹메탈재의 부착성능을 평가하였고, 각 보강방법에 대한 강성 증가 효과와 항복 후의 연성 증진 효과를 파악하였다. 그리고, 각 시험체의 실험 결과에 대한 비교를 통하여 더 나은 보강효과를 발휘할 수 있는 방안을 제시하였다.

• Journal of Biosystems Engineering
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• 제22권4호
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• pp.391-400
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• 1997

Using the soil bin systems, this study was carried out to investigate the tilling load characteristic for the three kinds of Japanese rotary blade and the possibility of common use for power tiller and tractor rotary. The results obtained from the study are summarized as follows : 1. At all tested soils. the average and maximum tilling torque of all tested blades increased as the tillage pitch did. 2. The torque requirements of newly designed and produced blade was less than that of blade which has been used on power tiller and tractor rotary. 3. The maximum tilling torque of new ONE were decreased 7%, 10~11％, 27% in comparing with another blades at clay loam, loam and sandy loam, respectively. 4. According to observation of the extent of soil adhesion on blade and the contact aspect of blade, new ONE is the most excellent of all tested rotary blades and till smoothly not to compress the untilled soil. From the results of this study. the newly developed blade(new ONE) proved to be good tilling load performance and had a conclusion that it is possible to use it on power tiller and tractor rotary in common.