• Journal of the Korean Society for Aviation and Aeronautics
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• v.4 no.1
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• pp.7-24
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• 1996

A methodology has been developed for predicting aircraft reliability incorporating both C.C.F.s(Common-Cause Failures), and phased missions. Failure behaviour of an aircraft, or it's systems are predicted. Both independent failures, and C.C.F.s, are modelled by the Markov process, and simulated using Monte Carlo sampling with the robust variance reduction method. Prediction of safety and reliability is made through discrete-event simulation of aircraft operations. A case study is described for investigating the safety and reliability of the propulsion system of two-, three- and four-engined aircraft. This is particularly important for the design of ETOPS(Extended Range of Two-Engined Aircraft Operations) and results are presented for the cases with, and without the effect of C.C.F.s.

• The Journal of Natural Sciences
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• v.11 no.1
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• pp.45-54
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• 1999

In epistatic grouping of uvs genes in A. nidulans based on the sensitivities to 4-NQO, the same epistatic grouping was obtained as those for UV and MMS-sensitivities. Based on the MMS-sensitivities, uvsA demonstrated synergistic interactions to uvsF and uvsH, the UvsF group genes, but exhibited epistatic interactions to uvsB and uvsC. The same epistatic grouping was also seen for uvsI when UV was irradiated after 4h germination of conidia, showing synergistic interactions to uvsH, uvsC, and uvsB. However, epistatic interactions were observed with uvsF, which were different from those obtained in quiescent conidia by UV. Intergenic and intragenic recombination frequencies were normal in uvsI compared with wild type.

• Korean Journal of Materials Research
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• v.5 no.6
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• pp.657-666
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• 1995

Chemical vapor deposition of copper from the Cu(hfac)$_2$, Cu(II) hexafluoroacetylacetonate precursor, has been thermodynamically investigated by the minimization of Gibbs free energy of the system. For the Cu(hfac)$_2$-Ar system, carbon incorporation into the deposited films was observed in all the process conditions, which is presumably inherent from the thermal decomposition of the Cu(hfac)$_2$, precursor. For the Cu(hfac)$_2$-H$_2$system, lower temperatures were required than those of the Cu(hfac)$_2$-Ar system for the depositon of the copper films. Furthermore, we identified that the appearances of the condensed phases were sequentially changed from the codeposits of C(s)+CuF(s) to C(s)+CuF(s)+Cu(s), C(s)+Cu(s), Cu(s), and C(s), when the H$_2$input ratio and th reaction temperature were increased.

• Bulletin of the Korean Mathematical Society
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• v.36 no.3
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• pp.441-450
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• 1999

In this paper we first evaluate the conditional Wiener integral of certain functionals using a Park and Skoug's formula. and we also evaluate the conditional wiener integral E(F│$X_\alpha$) of functional F on C[0, T] given by $F(x)=exp\{{\int_0}^T s^kx(s)ds\}$ for a general conditioning function $X_\alpha$ on C[0,T].

• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.04a
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• pp.163-163
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• 1993

대상환자는 모두 23명이였으여, 이중 12명은 fluconazole을, 11명은 nystatin을 투여받았다. 두 군사이에 연령, 남여비, 기저질환, 진균감염의 위험요소는 차이가 없었다. 투약기간은 fluconazole군(F)이 24일, nystatin군(N)이 23일이였다. 중도탈락은 3례로 F중 MRSA ？혈증 1례, N중 오심, 구토 1례외 Stevens-Johnson증후군 1례였다. 평가가능한 20례중, F 11례중 8례와, N 9례중 4례에서 진균감염중의 예방에 성공하였고, F 3례와 N 5례는 실패하였다. 실패한 F 3례는 코의 피부조직에서 aspergillus가 중명된 1례와 경험적으로 amphotericin을 투여한 2례였고, N 5례는 혈액배양에서 Candida tropicalis가 분리된 1례와 경험적 amphotericin을 받은 4례였다. 진균의 colonization은 F중 3균주는 치료중 소실되었으나, 2례는 증가하였다. N은 1균주가 소실된 반면, 3례는 증가하였다. Colonization이 증가한 F 2례는 C. albicans와 Trichosporon beigelli가 대변에서 분리된 경우이고. M 3례는 대변에서 C. albicans가 분리된 1례, 구강에서 aspergillus가 분리된 1례, 혈액배양에서 C. tropicalis가 분해된 1례였다. 부작용은 오심 구토가 F중 1례, N중 2례 였으며, 이중 N의 1례는 증상이 심하여 투약을 중지하였다. 간기능 검사상 SGOT/SGPT의 상승은 F 12중 3례, N 11중 2례에서 관찰되었으나, 두 군사이에 통계학적으로 유의한 차이는 없었다.

• Asian-Australasian Journal of Animal Sciences
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• v.2 no.3
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• pp.228-230
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• 1989

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1993.06a
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• pp.842-844
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• 1993

We present a F.L.C. (Fuzzy Logic Controller) to control of the oscillation frequency of a V.C.X.O. (Voltage Controled Crystal Oscillator). This F.C.X.O. maintains stable its oscillation frequency inside a range of 1 ppm (one part per millon), with temperature between -55$^{\circ}C$ to＋75$^{\circ}C$.

• Kyungpook Mathematical Journal
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• v.57 no.4
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• pp.667-676
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• 2017

We study the positive $C^1$ function z = f(x, y) defined on the plane ${\mathbb{R}}^2$. For a rectangular domain $[a,b]{\times}[c,d]{\subset}{\mathbb{R}}^2$, we consider the volume V and the surface area S of the graph of z = f(x, y) over the domain. We also denote by (${\bar{x}}_V,\;{\bar{y}}_V,\;{\bar{z}}_V$) and (${\bar{x}}_S,\;{\bar{y}}_S,\;{\bar{z}}_S$) the geometric centroid of the volume under the graph of z = f(x, y) and the centroid of the graph itself defined on the rectangular domain, respectively. In this paper, first we show that among nonconstant $C^2$ functions with isolated singularities, S = kV, $k{\in}{\mathbb{R}}$ characterizes the family of catenary rotation surfaces f(x, y) = k cosh(r/k), $r={\mid}(x,y){\mid}$. Next, we show that one of $({\bar{x}}_S,\;{\bar{y}}_S)=({\bar{x}}_V,\;{\bar{y}}_V)$, $({\bar{x}}_S,\;{\bar{z}}_S)=({\bar{x}}_V,\;2{\bar{z}}_V)$ and $({\bar{y}}_S,\;{\bar{z}}_S)=({\bar{y}}_V,\;2{\bar{z}}_V)$ characterizes the family of catenary rotation surfaces among nonconstant $C^2$ functions with isolated singularities.

• 한국초전도학회:학술대회논문집
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• v.10
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• pp.61-64
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• 2000

$^{11}$B NMR measurements have been performed to investigate local electronic structure and 4f spin dynamics for TbNi$_2$B$_2$C single crystal. $^{11}$B NMR spectra show three resonance peaks due to the quadrupolar interaction. Shift and linewidth are huge and strongly temperature-dependent. In addition, both are proportional to magnetic susceptibility, indicating that the hyperfine field at the boron site originates from the 4f spins of Tb. $^{11}$B NMR shift and relaxation rates show high anisotropy for field parallel and perpendicular to the c-axis. Anisotropy of the shift and the relaxation rates suggests that the hyperfine field perpendicular to the c-axis is larger.

• Journal of the Korean Society of Costume
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• v.27
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• pp.121-132
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• 1996

This study showed the proper pigment extract in the Phe. Dyeing which is the basic dye of the natural plants dyeing,. Also it compared and examined the K/S the promotion of the color fastness and the effect of color difference change were attended by mordants and method of mordanting. 1. The most absorbance of Phellodendron. sol-ution is 330nm berberine is 430nm. 2. The best and proper temperature to extrat Phe,. was 80 and dyeing solution for 24 hours. 3. The pH effect was stable in the absorbances and color differences change. 4. Mordanted group increased the absorbances compared to non-mordanted sample. In case depth the most absorbance of Al. Sn. K. Cu and C. A solution were in 3% Fe and Cr were in 5%. In the color difference change they became dark reduced greenish and increased yellowish when their absorbances were in 3% 5. K./S was recoginzed by tainnin and fe, K/S was more increased pre-mordants than post-mordants. 6. Fe is the unchangable mordant in the color difference change and pre-mordants is more stable than post-mordants in the difference color. 7. Generally light C. F indicated more than grade 2 and light C. F, was much improved in post-mordanted by alumium potassium potass-ium dichromate. Washing C.F was improved in mordanted by tainnin and ferrous suulfate mordanted group was better than non-mordanted sample. Perspir-ation C,F was more stable in acid than alkali. Dry cleaning C.F indicated more than grade. 4.