• KIEE International Transactions on Electrophysics and Applications
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• 제5C권5호
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• pp.204-210
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• 2005

Alternating current (AC) losses of two Bi-2223 ([Bi, Pb]: Sr: Ca: Cu: O = 2:2:2:3) tapes [(Tape I, un-twist-pitch) and the other with a twist-pitch of 10 mm (Tape II)] were measured and compared. These samples, produced by the powder-in-(Ag) tube (PIT) method, are multi-filamentary. Also, it's produced by non-twist and different twist pitch (8, 10, 13, 30, 50 and 70 mm). The critical current measurement was carried out under the environment in liquid Nitrogen and in zero-field by 4-probe method. Susceptibility measurements were conducted while cooling in a magnetic field. Flux loss measurements were conducted as a function of ramping rate, frequency and field direction. The AC flux loss increases as the twist-pitch of the tapes decreased, in agreement with the Norris Equation. Neutron-diffraction measurements have been carried out investigate the crystal structure, magnetic structures, and magnetic phase transitions in Bi-2223([Bi, Pb]:Sr:Ca:Cu:O)

• 한국광학회:학술대회논문집
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• 한국광학회 2008년도 동계학술발표회 논문집
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• pp.293-294
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• 2008

Using bi-direction SOA based Extension system, FTTH can enhance PON system by increasing both the upstream and downstream link budget. This increased link budget can be used to extend the distance, increase the split ratio or both. The bi-direction SOA regenerates signals using all-optical amplification, and is therefore transparent to data rate or protocol. The bi-direction SOA supports legacy as well as future FTTx standards. This is based on SOA's proprietary technology platform for the manufacturing of advanced discrete photonics and photonic integrated circuits (PICs). Because the bi-direction SOA uses the same InP semiconductor technology used in virtually all telecom lasers, it is able to amplify signals at 1310 and 1490 nm, wavelengths not accessible with commercial fiber-amplifier (EDFA) technology. Due to the extremely fast response time of the InP semiconductor optical amplifiers inside, the SOA can accommodate both continuous (downstream) and bursty (upstream) traffic.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집
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• pp.300-303
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• 2001

BSCCO thin films are fabricated via a co-deposition process by an ion beam sputtering with an ultra-low growth rate, and sticking coefficients of the respective elements are evaluated. The sticking coefficient of Bi element exhibits a characteristic temperature dependence : almost a constant value of 0.49 below 730$^{\circ}C$ and decreases linearly with temperature over 730$^{\circ}C$. This temperature dependence can be elucidated from the evaporation and sublimation rates of bismuth oxide, Bi$_2$O$_3$, from the film surface. It is considered that the liquid phase of the bismuth oxide plays an important role in the Bi 2212 phase formation in the co-deposition process.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 추계학술대회 논문집 전기물성,응용부문
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• pp.119-121
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• 2002

$Bi_2Sr_2CuO_x$ thin films were fabricated by atomic layer-by-layer deposition using an ion beam sputtering method, 10 wt% and 90 wt% ozone mixed with oxygen were used with ultraviolet light irradiation to assist oxidation. At early stages of the atomic layer by layer deposition, two dimensional epitaxial growth which covers the substrate surface would be suppressed by the stress and strain caused by the lattice misfit, then three dimensional growth takes place. Since Cu element is the most difficult to oxidize, only Sr and Bi react with each other predominantly, and forms a buffer layer on the substrate in an amorphous-like structure, which is changed to $SrBi_2O_4$ by in-situ anneal.

• 한국염색가공학회지
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• 제34권3호
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• pp.146-156
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• 2022

In this study, the dyeing properties of double knit fabric composed of PET/PTT bi-component fiber and quick dry fiber were examined with disperse dyes. In addition, the shrinkage characteristics were investigated during the dyeing process. The K/S values and shrinkage rate of PET/PTT bi-component fiber were higher than those of PET/co-PET bi-component fiber and quick dry fiber. In the dye bath, dye migration of exhausted on PET/PTT bi-component fiber to quick dry fiber was found at high dyeing temperature. It was not found that there was a significant difference in K/S value on dyeing temperature between 115℃ and 130℃. But the slight color difference of two sides of a double knit fabric was found.

• 한국기계가공학회지
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• 제4권2호
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• pp.3-9
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• 2005

In this study, the chip breaking characteristics of S, PbS and BiS free machining steels have been assessed. PbS free machining steel shows the lowest value of chip thickness ($t_c$) under the same cutting conditions. SM10C steel has the largest value of the chip cross-section area ratio ($R_{CA}$). As the feed rate becomes larger the chip breaking cycle time ($T_B$) decreases and the chip breaking index ($C_B$) increases. The properly controlled-C type chip has been obtained with the value of $C_B$ between 0.05 and 0.2. Free machining steel, PbS produces the properly controlled-C type chip in a wider feed rate range than other steels.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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• pp.185-186
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• 2008

The $Sr_{0.7}Bi_{2.3}Nb_2O_9$(SBN) thin films are deposited on Pt-coated electrode(Pt/Ti/SiO2/Si) using RF sputtering method at various substrate temperature. The optimum conditions of RF power and Ar/O2 ratio were 60[W] and 70/30, respectively. The rougness showed about 4.33[nm]. Deposition rate of SBN thin films was about 4.17[nm/min]. The capacitance of SBN thin films were increased with the increase of substrate temperature.

• Journal of Dental Anesthesia and Pain Medicine
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• 제22권5호
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• pp.339-348
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• 2022

Background: To compare the anesthetic efficacy of supplemental buccal infiltration (BI) (1.7 ml) versus intraligamentary (IL) injection containing 0.4 ml of 4% articaine with 1:100.000 epinephrine after an inferior alveolar nerve block (IANB) with 1.7 ml 2% lidocaine in the first and second mandibular molars diagnosed with irreversible pulpitis (IP). Methods: One hundred subjects diagnosed with IP of either the mandibular first (n = 50) or second molars (n = 50) and failed profound anesthesia following an IANB were selected. They randomly received either the IL or BI techniques of anesthesia. Pain scores on a 170 mm Heft-Parker visual analog scale were recorded initially, before, and during supplemental injections. Furthermore, pulse rate was measured before and after each supplemental injection. During the access cavity preparation and initial filing, no or mild pain was assumed to indicate anesthetic success. The chi-square test, Mann-Whitney U test, and independent samples t-test were used for the analyses. Results: The overall success rates were 80% in the IL group and 74% in the BI group, with no significant difference (P = 0.63). In the first molars, there was no significant difference between the two techniques (P = 0.088). In the second molars, IL injection resulted in a significantly higher success rate (P = 0.017) than BI. IL injection was statistically more successful (P = 0.034) in the second molars (92%) than in the first molars (68%). However, BI was significantly more successful (P = 0.047) in the first molars (88%) than in the second molars (64%). The mean pulse rate increase was significantly higher in the IL group than in the BI group (P < 0.001). Conclusions: Both the IL and BI techniques were advantageous when used as supplemental injections. However, more favorable outcomes were observed when the second molars received IL injection and the first molars received BI.

• 한국결정성장학회지
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• 제9권6호
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• pp.585-589
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• 1999

자동직경제어방식이 부착된 쵸크랄스키법에 의해 $Bi_4Ge_3O_{12}$(BGO) 단결정을 육성하기 위해 저항발열식로를 자체설계로 제작하여 사용하였다. 로 내의 온도 구배는 열적구조를 변화하면서 측정하였다. 각각의 변화된 온도구배와 평평한 계면을 갖는 임계 회전속도의 의존성에 대해 연구하였고 또한 저항발열식 가열에서 수직온도구배의 중요성을 지적하였다. 그것은 RF 가열방식을 사용하였을 때 다른 저자들에 의해 얻어진 결과와 비교되었다. 단결정 육성을 위한 최적조건은 다음과 같다. 산소 분위기하에서 2mm/h로 인상속도를 고정하고 성장이 진행함에 따라 회전속도를 30에서 23rpm으로 변화하였고, 수평 및 수직 온도구배는 융액근처에서 각각 50과 $40^{\circ}C$/cm이었고, 조성은 화학양론 조성이었다.

• 한국전기전자재료학회논문지
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• 제16권5호
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• pp.378-384
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• 2003

Etching species in CF$_4$/Ar plasma and the behavior of etching rate of Bi$_4$-$_{x}$L$_{x}$rTi$_3$O$_2$ (BLT) films were investigated in inductively coupled plasma (ICP) reactor in terms of etch parameters. The etching rate as functions of CF$_4$ contents showed the maximum 803 $\AA$/min at 20% CF$_4$ addition in CF$_4$/Ar plasma. The increase of RF power and DC bias voltage caused to an increase of etch rate. The variation of relative volume densities for F and he atoms were measured with the optical emission spectroscopy (OES). The chemical states of BLT were investigated with using X-ray photoelectron spectroscopy (XPS). XPS narrow scan analysis shows that La-fluorides remained on the etched surface. The presence of maximum etch rate at CF$_4$(20%)/Ar(80%) may be explained by the concurrence of two etching mechanisms such as physical sputtering and chemical reaction. The roles of he ion bombardment include destruction of metal (Bi, La, Ti)-O bonds as well as assistant for chemical reaction of metals with fluorine atoms.oms.