• 한국표면공학회지
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• 제35권3호
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• pp.127-132
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• 2002

High speed performance of ferroelectric Pb(Zr,Ti)$O_3$ (PZT) based capacitors is reported. La substitution up to 10% was performed to systematically lower the coercive and saturation voltages of epitaxial ferroelectric capacitors grown on Si using a ($Ti_{0.9}$ /$Al_{0.1}$ )N/Pt conducting barrier composite. Ferroelectric capacitors substituted with 10% La show significantly lower coercive voltage compared to capacitors with 0% and 3% La. This is attributed to a systematic decrease in the tetragonality (i.e., c/a ratio) of the ferroelectric phase. Furthermore, the samples doped with 10% La showed dramatically better retention and pulse width dependent polarization compared to the capacitors with 0% and 3% La. These capacitors show promise as storage elements in low power high density memory architectures.

• Plant Biotechnology Reports
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• 제3권2호
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• pp.135-138
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• 2009

Cell cultures of Cayratia trifolia (Vitaceae), a tropical lianas, were maintained in Murashige and Skoog's medium containing $0.25mg\;1^{-1}$ NAA, $0.2mg\;1^{-1}$ kinetin and casein hydrolysate $250mg\;1^{-1}$. Cell suspension cultures of C. trifolia accumulate stilbenes (piceid, resveratrol, viniferin, ampelopsin), which on elicitation by any of $500{\mu}M$ salicylic acid, $100{\mu}M$ methyl jasmonate, $500{\mu}M$ ethrel and $500mg\;1^{-1}$ yeast extract, added on the 7th day, were enhanced by 3- to 6-fold ($5-11mg\;1^{-1}$) by the 15th day.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 1999년도 춘계 학술발표회 논문집 Proceedings of EESK Conference-Spring
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• pp.275-283
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• 1999

To predict the dynamic behavior of the cylindrical liquid storage tank subjected to seismic ground motion three dimesional analysis with liquid-structure interaction must be performed, In this study a three dimensional dynamic analysis method over the frequency domain using FE-BE coupling technique which combines the efficiency of the boundary elements for liquid with the versatility of the finite shell elements for tank. The liquid region is modeled using boundary elements which can counter the sloshing effect at free surface and the structure region the tank itself is modeled using the degenerated finite shell elements. At the beginning of the procedure the equivalent mass matrix of the liquid is generated by boundary elements procedure. Then this equivalent mass matrix is combined with the mass matrix of the structure to produce the global mass matrix in the equation of the motion of fluid-structure interaction problem In order to demonstrate the accuracy and validity of the developed method the numerical results re compared with the previous studies. Finally the effects of the fluid-structure interaction on the natural frequency and dynamic response of the system are analyzed.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1993년도 하계학술대회 논문집 A
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• pp.281-283
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• 1993

A new method of EEG spindle waveform detection i s presented. The method combines the signal conditioning in the time-domin and the analysis of local spectrum in the frequency-domain. Fast computation methods, utilizing some effective approximations, are also suggested for the desist and implementation of the filter as well as for the computation of the local spectrum. The presented approach is especially useful for the real-time implementation of the waveform detection system under a general purpose microcomputer environment. The overall detection system is implemented and tested on-line with the total 24 hour data of selected four subjects. The result show the average agreement of 86.7% with the visually inspected result.

• 한국전자파학회논문지
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• 제12권2호
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• pp.227-233
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• 2001

본 논문에서는 전자파 장해 및 복사내성 측정의 대용 시험시설로서 활용될 수 있는 전자파 잔향실의 전자기장 특성에 관하여 연구되었다. 전자파 잔향실 내부에서의 필드 균일성을 확보하기 위하여, Shroeder 방식의 Quadratic Residue 확산기(diffuser)를 설계한 후, 확산기의 방향에 따른 3가지 배열 형태로 잔향실 내부에 적용하여, 필두 분포를 해석하였다. FDTD(Finite-Difference Time-Domin) 수치해석 방식을 이용하여 잔향실 내부의 필드 특성을 연구한 결과 확산기를 부착한 3가지 형태 모두 최대 변화범위 $\pm$3 dB 이내의 필드 균일도를 나타내었으며, type 3, 대칭형 구조의 확산기 형태가 효율이 가장 우수하다는 결과를 나타내었다.

• 한국진공학회지
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• 제7권3호
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• pp.248-254
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• 1998

PECVD(Plasma Enhanced Chemical Vapor Deposition) 방법을 이용하여 비정질 고 상 탄소 박막의 하나인 유사 다이아몬드(Diamond-Like-Carbon; DLC) 박막을 증착하였다. FT-IR Spectroscopy와 Raman Scattering 등을 통해 박막의 구조적 특징을 조사하였는데, 박막은 microcrystalline diamond domain과 graphitelike carbon domain들이 수소화된 $sp^3$사 면체 구조의 비정질 탄소에 의해 그물 구조로 연결되어진 것으로 보인다. 이러한 추정은 I-V 특성 조사의 결과와도 좋은 일치를 보이는데, 특히 I-V조사에서는 전류의 갑작스러운 증가가 관측되어졌으며 이것은 graphitelike carbon domin들간의 전자 tunneling 현상으로 이해되어진다. 그리고 대단히 얇은 탄소 박막에 대한 Raman산란 조사에서는 증착 초기 상 태에 $\beta$-SiC층이 형성되어지는 것을 확인할 수 있었다.

• 한국건설관리학회논문집
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• 제15권1호
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• pp.78-86
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• 2014

유닛 모듈러 공법은 공장생산에 의한 공기단축, 품질관리, 친환경성 등 기존공법과 다른 다양한 특징을 가지고 있다. 이러한 특징에도 불구하고 현재 국내에서는 군 병영시설, 학교, 소형주택에만 제한적으로 적용되고 있다. 본 연구에서는 모듈러 공법의 시장 확대 및 활성화를 위해 공동주택을 중심으로 특성요인들에 대한 중요도 및 기술수준을 IPA 기법을 통해 분석하여, 모듈러 시장의 활성화 방안을 제시하였다. 분석결과 유닛 모듈러 공법을 공동주택 시장에 적용함에 있어 사용성 및 경제성 측면의 특성요인들이 중요하게 평가되었으나, 현재 기술수준은 상대적으로 중요도가 낮은 시공성 측면의 특성요인들이 높게 나타났다. 유닛 모듈러 공법을 공동주택 시장에 적용하기 위해서는 시공성 측면의 높은 기술수준을 바탕으로 사용성, 경제성 측면의 특성요인에 대한 보다 집중적인 연구 개발이 필요할 것이다.

• Biomolecules & Therapeutics
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• 제8권2호
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• pp.153-159
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• 2000

A novel serine/threonine protein phosphatase with EF-hand motif, which belongs to PPEF family was partially cloned from rat brain cDNA by employing RT-PCR method. The size of the amplified clone was 1.6kbp. The amplified DNA was subcloned into pGEM-T-Easy vector and the resulting plasmid was maned as pGEM-rPPEF2. The nucleuotide sequence is shared by 88% with that of mouse PPEF-2 cDNA, and the deduced amino acid sequence reveal 92% homology with that of mouse PPEF-2 cDNA. The N-terminal region of the cloned rat brain PPEF contains a putative phosphatase catalytic domain (PP domain) and the C-terminal region contains multiple $Ca^{2+}$ binding sites (EF region). The putative catalytic domin (PP) and the EF-hand motif (EF) regions were subcloned into pGEX4T-1 and were overexpressed in E. coli DH5 as glutathione-S-transferase (GST) fusion proteins. Expression of the desired fusion protein was identified by SDS-PAGE and also by immunoblot analysis using monoclonal antibody against GST. The recombinant proteins were purified by glutathione-agarose chromatography. This report is first to demonstrate the cloning of PPEF family from rat brain tissues. The clone reported here would be invaluable for the investigation of the role of this new type-phosphatase in rat brain.

• 한국전자파학회논문지
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• 제29권1호
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• pp.42-49
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• 2018

본 논문에서는 WLAN(Wireless Local Area Network) 시스템에 적용 가능한 결합 접지 구조(DGS)를 갖는 마이크로스트립 급전 방식의 모노폴 안테나를 제작하였다. 제안된 안테나는 결함 접지 구조를 이용하여 이중 대역이 나타나게 하였으며, 모노폴 안테나는 두께를 단계별로 줄여가며 임피던스 정합을 용이하게 하였다. $44{\times}51{\times}1.6mm^3$의 크기로 모노폴 안테나 및 접지면의 크기를 변화시켜가며 최적화하여 WLAN의 2.4 GHz 대역과 5 GHz 대역을 만족할 수 있도록 하였다. FR-4 기판을 사용하여 제작 및 측정한 결과 VSWR(Voltage Standing Wave Ratio) 2 이하를 기준으로 210 MHz(2.29~2.50 GHz)와 900 MHz(5.05~5.95 GHz)의 대역폭을 얻었고 전방향성의 방사패턴을 얻었다.

• 대한간호학회지
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• 제22권3호
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• pp.297-315
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• 1992

Caring has been identified as the essence and unifying domin of nursing(Leininger). Many nurses believe that the art of nursing is comprised of actions that are predominantly caring in nature. Although caring has been the traditional ideology of nurses, it is only now beginning to emerge as the central construct for the development of nut sing research, theory and practice. The problem addressed by this study was to identify how hospitalized children and their nurses express the meaning of caring, how they think nurses should care for children and to describe their experiences of being cared for. The purpose was to provide theoretical understanding of caring as perceived in Korea to contribute to the development of Korean nursing knowledge. The subjects were 76 hospitalized children admitted to pediatric units in five teaching hospitals and 66 nurses who were caring for these children. In this descriptive study, data were collected from Nov 11, 1991 to Jan 30, 1992 by interviews and an open-ended questionnaire and analysed by van Kaam's method. Caring themes perceived by the children and their nurses were classified into eight categories, -helping, comfort, love, warmth(only by children), recovery from illness, health maintenance (only by nurses), presence, nurturance and responsibility. Ideal caring behaviors perceived by the children and their nurses were six categories, -to give help, provide comfort, give love, stay with, treat warmly and aid recovery. Subcategories of giving help were promptness and competence, detailed explanations and support and encouragement. Other subcategories of giving help reported only by nurses were individualizing care, recognizing needs and providing a familiar enviornment. Subcategories of maintaining comfort were making comfortable, alleviating pain ; one subcategory reported only by children was consolating. A subcategory of giving love was concern, two subcategories reported only by nurses were compassion and respect. Subcategories of staying with were playing with and touching : only nurses reported empathy, Subcategories of treating warmly were tenderness and kindness. In the experience of caring, there were 4 categories, -to give help, stay with, show concern and provide comfort. Both the hospitalized children and their nurses had experienced caring primarily from their mothers. Mothers' caring behaviors were direct, personal, basic, supportive nursing acts. On the other hand, nurses caring behaviors were task oriented skilled procedures and medically delegated acts. This study contributes understanding of the complexity of caring, more specifically the meaning and experience of caring and ideal caring behaviors. Research may be able to move into verification when instruments are developed to measure the complexity of caring beliefs, values and behaviors in Korea and other cultural settings.