• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.4
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• pp.339-343
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• 2006

We observed the application possibility of inductive coupler for the underground high-voltage power line communication by means of analysis of signal transmission characteristics and magnetic properties on annealing temperatures for high-permeability Fe-base amorphous alloys. The best electromagnetic and transmission characteristics were shown in nano-crystalline precipitated alloy annealed at temperature $510^{\circ}C$. The transmission characteristics in the low-frequency band depend on permeability of magnetic core materials and its properties of high-frequency band can be improved by impedance matching. Using the high pass filter embedded in the coupler, other noise signal band except for communication signals could be cut off.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.239-240
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• 2006

저손실 고투자율 특성을 가지는 ${\alpha}-Fe$ 나노결정 자심재료를 제조하기 위한 열처리 온도 변화에서, $510^{\circ}C$의 열처리 조건에서 가장 높은 투자율과 신호전송 특성을 나타내었다. 저주파 대역에서의 신호 전송 특성은 자심재료의 자기적 특성에 지배적인 영항을 받으며, 고주파 대역의 신호전송 특성은 임피던스 매칭으로 향상시킬 수 있었다. 그리고 커플러의 출력부에 신호증폭장치를 삽입하여 자기유도에 의해 신호가 커플링될 때 발생하는 삽입손실을 보완하여 커플러의 특성을 향상시킬 수 있었다.

• Korean Journal of Materials Research
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• v.29 no.12
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• pp.812-817
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• 2019

A zinc-air battery is one of most promising advanced batteries due to its high specific energy density, low cost, and environmental friendliness. However, zinc anodes in zinc-air batteries lead to several issues including self-discharge, corrosion reaction, and hydrogen evolution reaction (HER). In this paper, viscosity of electrolyte has been controlled to suppress the corrosion reaction, HER, and self-discharge behavior. Various viscosity average molecular weights of poly(acrylic acid) (PAA) are adopted to prepare the electrolyte. The evaporation of electrolytes is proportional to the increase in molecular weight. In addition, enhanced self-discharge behavior is obtained when the gelling agent with high molecular weight is used. In addition, the zinc-air cell assembled with lower viscosity average molecular weight of PAA (M_v ~ 450,000) delivers 510.85 mAh/g and 489.30 mAh/g of discharge capacity without storage and with 6 hr storage, respectively. Also, highest capacity retention (95.78 %) is obtained among studied materials.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.19 no.4
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• pp.503-510
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• 2012

Purpose: The purpose of this study was to identify the factors influencing emergency department (ED) nurses' turnover intention. Methods: The study was conducted with 241 nurses from ED of 20 general hospitals in Busan. The survey data were collected from May 1 to July 31, 2010 and were analyzed using frequencies, percentages, means, t-test, ANOVA, Pearson correlation coefficient and stepwise multiple regression with the SPSS Win 17.0 program. Results: There were statistically significant differences in turnover intention depending on age, regular change in department, and nursing experiences. A significant positive correlation was found between job stress and turnover intention and a significant negative correlation between organizational commitment and turnover intention. The significant factors influencing turnover intention were regular change in department, job stress, and organizational commitment, which explained about 13.7% of the variance. Conclusion: Considering this results, nursing managers should analyze these main factors which affect turnover intention and create ways to decrease turnover intentions, and thus decrease high turnover intention.

• Corrosion Science and Technology
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• v.8 no.3
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• pp.119-125
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• 2009

Corrosion assessment has a number of uses but the use considered here is as a precursor to Risk-Based Inspection (RBI) planning. Systematic methods consisting of technical modules of RBI program were used to assess the effect of specific corrosion mechanism on the probability of failure in equipments of petrochemical plants. Especially in part of the damage and corrosion assessment, screening step involved evaluating the combinations of process conditions and construction materials for each equipment item in order to determine which damage mechanisms are potentially active. For general internal corrosion, either API 510 or API 570 was applied as the damage rate in the calculation to determine the remaining life and inspection frequency. In some cases, a measured rate of corrosion may not be available. The technical modules of RBI program employ default values for corrosion, typically derived from published data or from experience with similar processes, for use until inspection results are available. This paper describes the case study of corrosion and damage assessment by using RBI methodology in petrochemical plant. Specifically, this paper reports the methodology and the results of its application to the petrochemical units using the $KGS-RBI^{TM}$ program, developed by the Korea Gas Safety Corporation to suit Korean situation in conformity with API 581 Codes.

• The Journal of Korean Academic Society of Nursing Education
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• v.19 no.4
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• pp.648-655
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• 2013

Purpose: This study was conducted to investigate the level of interpersonal attachment styles and love styles and to identify the differences of love styles according to interpersonal attachment styles among nursing students. Methods: Data were collected from 510 nursing students using a self-report questionnaire and analyzed by frequencies, Fisher's exact test, t-test, and ANOVA using the SPSS program. Results: In terms of interpersonal attachment styles, secure style was the most prevalent, and fearful style was the second highest in nursing students. There were significant differences in interpersonal attachment styles between upper and lower level nursing students, indicating the highest rate of secure style in the lower grade and the highest rate of fearful style in the upper grade. In love styles, the mean scores for eros and pragma style in nursing students were significantly higher in the upper grade than the lower grade. Love styles according to interpersonal attachment styles showed a significant difference for eros style. Conclusion: Our results might help nursing educators increase their understanding of interpersonal attachment styles and love styles in nursing students and counsel nursing students in interpersonal and romantic relationships. In addition, educational programs addressing interpersonal attachment styles should be developed and applied to nursing students.

• Journal of the korean academy of Pediatric Dentistry
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• v.24 no.3
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• pp.495-510
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• 1997

The purpose of this study was to evaluate the efficacy of several surface coating agents in preventing microleakage and increasing microhardness of light-cured glass ionomer restoration. 50 and 25 sound molar teeth were used for the microleakage test and microhardness test respectively. Data were analyzed statistically using Kruskal-Wallis and/or Mann-Whitney test. The results of the present study were as follows: 1. The effect of surface coating in reducing microleakage was proven only at the gingival margin of restorations with statistical significance(p<.05). 2. The distribution of microleakage score at gingival margin was shown to be better than that of occlusal margin in general but with no statistically significant differences(p>.05). 3. No statistically significant differences in microhardness could be found between groups (p>.05) regardless of depth of measurement. 4. Under the present experimental conditions, the types or application of surface coating agents did not impose any significant effect on microhardness of glass ionomer restorative material whereas the protective effect of surface coating in reducing microleakage was partly proven.

• Journal of applied mathematics & informatics
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• v.15 no.1_2
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• pp.503-510
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• 2004

Given vectors x and y in a Hilbert space, an interpolating operator is a bounded operator T such that Tx = y. An interpolating operator for n vectors satisfies the equation $Tx_i\;=\;y_i,\;for\;i\;=\;1,\;2,\;\cdots,\;n$. In this paper the following is proved: Let H be a Hilbert space and L be a commutative subspace lattice on H. Let H and y be vectors in H. Let $M_x\;=\;\{{\sum{n}{i=1}}\;{\alpha}_iE_ix\;:\;n\;{\in}\;N,\;{\alpha}_i\;{\in}\;{\mathbb{C}}\;and\;E_i\;{\in}\;L\}\;and\;M_y\;=\;\{{\sum{n}{i=1}}\;{\alpha}_iE_iy\;:\;n\;{\in}\;N,\;{\alpha}_i\;{\in}\;{\mathbb{C}}\;and\;E_i\;{\in}\;L\}. Then the following are equivalent. (1) There exists an operator A in AlgL such that Ax = y, Af = 0 for all f in ${\overline{M_x}}^{\bot}$, AE = EA for all $E\;{\in}\;L\;and\;A^{*}\;=\;A$. (2) $sup\;\{\frac{{\parallel}{{\Sigma}_{i=1}}^{n}\;{\alpha}_iE_iy{\parallel}}{{\parallel}{{\Sigma}_{i=1}}^{n}\;{\alpha}_iE_iy{\parallel}}\;:\;n\;{\in}\;N,\;{\alpha}_i\;{\in}\;{\mathbb{C}}\;and\;E_i\;{\in}\;L\}\;<\;{\infty},\;{\overline{M_u}}\;{\subset}{\overline{M_x}}$ and < Ex, y >=< Ey, x > for all E in L.

• Molecules and Cells
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• v.37 no.7
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• pp.503-510
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• 2014

Lymphatic vessels provide essential roles in maintaining fluid homeostasis and lipid absorption. Dysfunctions of the lymphatic vessels lead to debilitating pathological conditions, collectively known as lymphedema. In addition, lymphatic vessels are a critical moderator for the onset and progression of diverse human diseases including metastatic cancer and obesity. Despite their clinical importance, there is no currently effective pharmacological therapy to regulate functions of lymphatic vessels. Recent efforts to manipulate the Vascular Endothelial Growth Factor-C (VEGFC) pathway, which is arguably the most important signaling pathway regulating lymphatic endothelial cells, to alleviate lymphedema yielded largely mixed results, necessitating identification of new targetable signaling pathways for therapeutic intervention for lymphedema. Zebrafish, a relatively new model system to investigate lymphatic biology, appears to be an ideal model to identify novel therapeutic targets for lymphatic biology. In this review, we will provide an overview of our current understanding of the lymphatic vessels in vertebrates, and discuss zebrafish as a promising in vivo model to study lymphatic vessels.

• Ocean and Polar Research
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• v.35 no.4
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• pp.291-298
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• 2013

In order to investigate the topography and exposure duration of the Siheung tidal flat, tidal ranges and DEM constructed by remote sensing techniques were analyzed. A cross-sectional diagram of the intertidal area reveals that it is relatively flat in the upper zone and then abruptly plunges into the bottom of the main channel where elevations increase in an upstream direction. The waterline during the Highest Low Water (HLW) is drawn back to the bottom of the channel at the middle part of the tidal flat and is formed along the slant of the channel during the Lowest High Water (LHW). The intertidal zone is located between -410 cm and 510 cm in terms of elevation and its total area is $0.65km^2$. An area between the Highest High Water (HHW) and Lowest High Water (LHW), occupying about 80% of the total area, occupies $0.52km^2$ of total area and accounts for 56% of the exposure duration. The boundary of wetland protection area in the Siheung tidal flat did not exactly coincide with the intertidal regime and differs by more than 15%. This study, which precisely analyzed the tidal flat area, tidal environment, and topography, would be useful in making a conservation plan and in learning how to use a wetland protection area in a sustainable manner.