• Journal of the Korean institute of surface engineering
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• v.35 no.3
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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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• v.3 no.2
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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.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1999.04a
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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.

• Proceedings of the KIEE Conference
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• 1993.07a
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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.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.12 no.2
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• pp.227-233
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• 2001

Electromagnetic field characteristics of Reverberation chamber, which could be applicable for an alternative test facility of electromagnetic interference and radiated electromagnetic susceptibility have been investigated. To obtain the required field uniformity of reverberation chamber, Schroeder method Quadratic Residue Diffuser was designed to be applied to chamber. In this paper, 3 different types of diffusers depending on diffuser's periodic direction have been used to investigate field characteristics of each type by using FDTD numerical method. The results show all 3 types of reverberation chambers have below $\pm$3 dB tolerance of field uniformity characteristics, and the symmetrical, type 3, structure show better results among them.

• Journal of the Korean Vacuum Society
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• v.7 no.3
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• pp.248-254
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• 1998

DLC(Diamond-Like-Carbon) thin film, one of the solid state amorphous carbon films, has been deposited by the method of PECVD (Plasma Enhanced Chemical Vapor Deposition). The structural features have been characterized using both FT-IR Spectroscopy and Raman Scattering. The film is considered to consist of microcrystalline diamond domains and graphitelike carbon domains, which are interconnected by hydrogenated $sp^3$ tetrahedral carbons. This shows a good agreement with the results by I-Vmeasurements. In I-Vstudy, the sudden increase of current has been observed and this phenomenon is understood to be due to the tunneling effect between graphitelike domains. A characteristic feature related to the $\beta$-SiC has been identified in the study of Raman Scattering for the very thin film, which suggests that a buffer layer forms at the interface of the Si substrate and the carbon film.

• Korean Journal of Construction Engineering and Management
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• v.15 no.1
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• pp.78-86
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• 2014

Modular system is a construction method which installs factory-manufactured units on site. It enables to reduce the duration and improve the quality of the construction. Nevertheless, the unit modular system is restrictively applied to domestic market such as barracks, education facilities, low-rise housing. To motivate the application of unit modular system, this study figures out important attributes of the unit modular system in a domestic construction market. Finally this study suggest marketing strategies and influential factors by Importance-Performance Analysis(IPA) based on those attributes focusing on the apartment housing. As a result, Unit modular System in the domestic market has strength on constructability, but it show weakness on usability and economic aspects which are more important in apartment housing market. Thus an improved technology in usability and economic aspects are required to activate the market.

• Biomolecules & Therapeutics
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• v.8 no.2
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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.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.29 no.1
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• pp.42-49
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• 2018

In this paper, a dual-band microstrip-fed monopole antenna with a DGS(defected ground structure) for WLAN(wireless local area network) applications is presented. The antenna consists of a monopole and a defected ground, which were etched on both sides of the FR-4 substrate. The defected ground structure was used to obtain the dual band, while the step-by-step reduction in the monopole width was used to improve the impedance matching of the antenna. The antenna has an overall compact size of $44{\times}51{\times}1.6mm^3$, which was optimized by varying the size of the monopole and the ground plane such that it may resonate at the 2.4 GHz and 5 GHz bands of the WLAN. The measurement results showed that the antenna operates in the frequency band of 210 MHz(2.29~2.50 GHz) and 900 MHz(5.05~5.95 GHz) for a VSWR under 2, and showed omnidirectional radiation pattern at all desired frequencies.

• Journal of Korean Academy of Nursing
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• v.22 no.3
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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.