• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.8
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• pp.852-858
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• 2004

An alkoxide-based sol-gel method was used to fabricate $Ba_{0.6}Sr_{0.4}TiO_{3}$thin films doped by Bi from 5 to 20 mol% on a Pt/Ti/$SiO_2$/Sisubstrate. The structural and dielectric properties of BST thin films were investigated as a function of Bi dopant concentration. The dielectric properties of the Bi doped BST films were strongly dependent on the Bi contents. The dielectric constant and dielectric loss of the films decreased with increasing Bi content. However, the leakage current density of the 10 mol% Bi doped $Ba_{0.6}Sr_{0.4}TiO_{3}$ thin film showed the lowest value of 5.13$\times 10^{-7} A/{cm}^2$ at 5 V. The figure of merit (FOM) reached a maximum value of 32.42 at a 10 mol% Bi doped $Ba_{0.6}Sr_{0.4}TiO_{3}$thin films. The dielectric constant, loss factor, and tunability of the 10 mol% Bi doped $Ba_{0.6}Sr_{0.4}Tio_{3}$ thin films were 333, 0.0095, and 31.1%, respectively.

• Human Ecology Research
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• v.58 no.3
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• pp.375-390
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• 2020

This paper explored the marriage migrant mothers' experiences of parenting bi-ethnic children in South Korea based on the concepts of ethnic socialization and intersectionality. We analyzed in-depth interviews of 22 marriage migrant women from Vietnam residing in the capital region of South Korea. They had at least one child whose biological father is Korean. Children were 5 years old or older, attending preschool or elementary school. Five types of bi-ethnic socialization strategies were identified, which provide portraits of different situations in which marriage migrant women were placed. The five strategies that emerged from the data were 1) "Natural practice of bi-ethnic socialization" including two heterogeneous groups, "Coexistence of two cultures" and "Mixture of two cultures", 2) "Active practice of bi-ethnic socialization", 3) "Struggling practice of bi-ethnic socialization", 4) "Silence on bi-ethnic socialization", and 5) "Suppressed bi-ethnic socialization". The strategies of bi-ethnic socialization that marriage migrant women chose to raise their children reflected personal perceptions of Korean society and individual ethnic identity formed within Korean society. This study complements existing research on ethnic socialization by examining how ethnic socialization practices are shaped by multiple contexts marriage migrant women embedded in Korean society.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.04b
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• pp.18-21
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• 2004

An alkoxide-based sol-gel method was used to fabricate $Ba_{0.6}Sr_{0.4}TiO_3$ thin films doped by Bi from 5 to 20 mol% on a $Pt/Ti/SiO_2/Si$ substrate. The structural and dielectric properties of BST thin films were investigated as a function of Bi dopant concentration. The dielectric properties of the Bi doped BST films were strongly dependent on the Bi contents. The dielectric constant and dielectric loss of the films decreased with increasing Bi content. However, the leakage current density of the 10 mol% Bi doped $Ba_{0.6}Sr_{0.4}TiO_3$ thin film showed the lowest value of $5.13{\times}10^{-7}\;A/cm^2$ at 5 V. The figure of merit (FOM) reached a maximum value of 32.42 at a 10 mol% Bi doped $Ba_{0.6}Sr_{0.4}TiO_3$ thin films. The dielectric constant, loss factor, and tunability of the 10 mol% Bi doped $Ba_{0.6}Sr_{0.4}TiO_3$ thin films were 333, 0.0095, and 31.1%, respectively.

• Journal of Information Technology Applications and Management
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• v.24 no.1
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• pp.45-61
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• 2017

Business intelligence has been attracting much attention these days. Despite such popularity of BI systems, it is widely known that about a half of BI system projects have failed. To grasp why many BI projects end in failure and what factors would make BI projects less failure-prone, a number of BI studies were made to produce a variety of CSFs. However, there is a paucity of information on whether these CSFs are distinctive from those of typical information systems. By identifying how BI CSFs differ from CSFs of typical information systems, we would be able to explain why most BI projects are more likely to be failure. It is believed that a corrective measure about CSFs will lead to more success in future BI projects. In addition, though there have been a number of similar types of BI systems such as decision support systems and executive information systems in existence, there was no study to determine whether there is ever a discrimination between CSFs of BI systems and the similarly-titled systems. This study is to answer these questions using a literature review analysis. The findings of our study are expected to be helpful in a successful implementation of BI systems.

• Journal of Electrical Engineering and Technology
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• v.2 no.1
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• pp.98-101
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• 2007

Yttrium(Y)-substituted bismuth titanate $(Bi_{4-x},Y_x)Ti_3O_{12}$ [x=0, 0.25, 0.5, 0.75, 1](BYT) thin films were deposited using an RF sputtering method on the $Pt/TiO_2/SiO_2/Si$ substrates. The structural properties and electrical properties of yttrium-substituted $(Bi_4-xYx)Ti_3O_{12}$ thin films were analyzed. The remanent polarization of $(Bi_4-xYx)Ti_3O_{12}$ films increased with increasing Y-content. The $(Bi_{3.25}Y_{0.75})Ti_3O_{12}$ films fabricated using a top Au electrode showed saturated polarization-electric field(P-E) switching curves with a remanent polarization(Pr) of $8{\mu}C/cm^2$ and coercive field (Ec) of 53 kV/cm at an applied voltage of 7 V. The $(Bi_{3.25}Y_{0.75})Ti_3O_{12}$ films exhibited fatigue-free behavior up to $4.5{\times}10^{11}$ read/write switching cycles at a frequency of 1MHz.

• Korean Journal of Materials Research
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• v.12 no.12
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• pp.962-966
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• 2002

The $SrBi_2$$Nb_2$$O_{9}$ (SBN) thin films were deposited with $SrNb_2$$O_{6}$ / (SNO) and $Bi_2$$O_3$ targets by co-sputtering method. For the growth of SBN thin films, we adopted the various power ratios of two targets; the power ratios of the SNO target to $Bi_2$$O_3$ target were 100 W : 20 W, 100 W : 25 W, and 100 W : 30 W during sputtering the SBN films. We found that the electrical properties of SBN films were greatly dependent on Bi content in films. The $Bi_2$Pt and $Bi_2$$O_3$ phase as second phases occurred at the films with excess Bi content greater than 2.4, resulting in poor ferroelectric properties. The best growth condition of the SBN films was obtained at the power ratio of 100 W : 25 W for the two targets. At this condition, the crystallinity and electrical properties of the films were improved at even low annealing temperature as $700^{\circ}C$ for 1h in oxygen ambient and the Sr, Bi and Nb component in the SBN films were about 0.9, 2.4, and 1.8 respectively. From the P-E and I-V curves for the specimen, the remnant polarization value ($2P_{r}$) of the SBN films was obtained about 6 $\mu$C/c $m^2$ at 250 kV/cm and the leakage current density of this thin film was $2.45$\times$10^{-7}$ $A/cm^2$ at an applied voltage of 3 V.V.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.6
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• pp.1115-1121
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• 2007

[ $Bi_2Sr_2Ca{_{n-1}}Cu_nO_x$ ](n=0,1,2) thin fans have been fabricated by co-deposition at an ultra-low growth rate using ion beam sputtering(IBS) method. Bi 2212 phase appeared in the temperature range of 750 and $795^{\circ}C$ and single phase of Bi 2201 existed in the lower region than $785^{\circ}C$. Whereas, $PO_3$ dependance on structural formation was scarcely observed regardless of the pressure variation. And high quality of c-axis oriented Bi 2212 thin film with $T_c$(onset) of about 90 K and $T_c$(zero) of about 45 K is obtained. Only a small amount of CuO in some films was observed as impurity, and no impurity phase such as $CaCuO_2$ was observed in all of the obtained films.

• Journal of the Korean Institute of Rural Architecture
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• v.11 no.1
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• pp.9-16
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• 2009

This research surveyed the native resources which BiBo(replenishing shortages by helping each other) landscapes have been preserved by aiming at the village settlement spaces of five cities and counties in Gangwon Youngseo province. This research reveals that BiBo landscape patterns of 41 village forests, 23 BiBo symbols, and 6 BiBo ponds were surveyed. The village forests are all 41 places, and were mainly made on the plains in front of villages. BiBo functions of the forests were in the order of the land obstructing the view of the mouth of a river which is the most as 13 places, the land obstructing the view of the mouth of river, situation complements, village protection, and protection against wind. Bibo symbols were all 23 places. Towers, stone towers, menhirs, and Maitreya stones were 12 places, Jangseungs(a signpost raising on the entrance of the village or a temple) were 6 places, Sotdae(a pole raising at the entrance of the village as the symbol of a board or a village protecting deity) was 1 place, and the others were made multiply in 4 places. Bibo symbols were located at 21 places in front of villages. The village protection in Bibo functions was 6 places. 6 Bibo ponds were surveyed. Most Bibo ponds were made for earth power leakage prevention.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.23-23
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• 2010

The $Bi_2Mg_{2/3}Nb_{4/3}O_7$ (BMNO)-Bi composite films sandwiched by an $Al_2O_3$ protection layer exhibited a linear increase of a dielectric constant with increasing thickness and the 1000nm-thick BMNO-Bi composite films showed a dielectric constant (~220) higher than that of its bulk material (~210), keeping a low leakage current density of about $0.1{\mu}A/cm^2$. An enhancement of the dielectric constant in the BMNO-Bi composite films was attributed to the hybrid model combined by a space charge polarization, dipolar response, and nano-capacitors. On the other hand, 1000nm-thick BMNO-Bi composite films sandwiched by 40nm-thick BMNO layer exhibited a dielectric constant of about 450 at 100 kHz and a leakage current density of $0.1{\mu}A/cm^2$ at 6V.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.1
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• pp.19-24
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• 2014

In this paper, a multiband LTE antenna satisfying LTE octa-band is proposed. The proposed antenna consists of a modified PIFA structure and a folded monopole which has the height of 4 mm. Each parts operates at lower and upper LTE band. Measured bandwidth(6 dB return loss) was 118 MHz(870~988 MHz) at the lower band and 1,107 MHz(1,650~2,757 MHz) at the upper band. The proposed antenna has a omni-directional radiation pattern and measured peak gains were 3.21 dBi at the lower band and 4.19 dBi at the upper band, respectively. The proposed antenna is expected to be utilized for future LTE-advanced system.