• 대한수학회보
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• 제39권1호
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• pp.123-131
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• 2002

Let A(p, k) (p, k$\in$N) be the class of functions f(z) = $z^{p}$ + $a_{p+k}$ $z^{p+k}$+… analytic in the unit disk. We introduce a subclass H(p, k, λ, $\delta$, A, B) of A(p, k) by using the Ruscheweyh derivative. The object of the present paper is to show some properties of functions in the class H(p, k, λ, $\delta$, A, B). B).

• 한국막학회:학술대회논문집
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• 한국막학회 2004년도 춘계 총회 및 학술발표회
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• pp.123-123
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• 2004

일반적인 활성슬러지 공정은 MLSS 1,500 - 3,000 mg/L 정도인데 MBR 공정은 보통 8,000 mg/L 이상의 농도로 운전할 수 있어, 높은 유기물 제거와 질산화 효율을 증가시킬 수 있다. 따라서 기존의 포기조 용량을 줄일 수 있으며 미생물의 자산화(Auto-Oxidation)가 증가하여 슬러지 발생량(Sludge Production)은 줄어들게 된다.(중략)

• 호남수학학술지
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• 제45권1호
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• pp.123-129
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• 2023

In this paper, we introduce the reverse of the operator Davis-Choi-Jensen's inequality. Our results are employed to establish a new bound for the Furuta inequality. More precisely, we prove that, if $A,\;B{\in}{\mathcal{B}}({\mathcal{H}})$ are self-adjoint operators with the spectra contained in the interval [m, M] with m < M and A ≤ B, then for any $r{\geq}{\frac{1}{t}}>1,\,t{\in}(0,\,1)$ $A^r{\leq}({\frac{M1_{\mathcal{H}}-A}{M-m}}m^{rt}+{\frac{A-m1_{\mathcal{H}}}{M-m}}M^{rt}){^{\frac{1}{t}}}{\leq}K(m,\;M,\;r)B^r,$ where K (m, M, r) is the generalized Kantorovich constant.

• 대한의생명과학회지
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• 제25권1호
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• pp.40-53
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• 2019

Of the Acinetobacter spp., A. baumannii (genospecies 2) is the most clinically significant in terms of hospital-acquired infections worldwide. It is difficult to perform Acinetobacter-related taxonomy using phenotypic characteristics and routine laboratory methods owing to clusters of closely related species. The ability to accurately identify Acinetobacter spp. is clinically important because antimicrobial susceptibility and clinical relevance differs significantly among the different genospecies. Based on the medical importance of pathogenic Acinetobacter spp., the distribution and characterization of Acinetobacter spp. isolates from 123 clinical samples was determined in the current study using four typically applied bacterial identification methods; partial rpoB gene sequencing, amplified rRNA gene restriction analysis (ARDRA) of the intergenic transcribed spacer (ITS) region of the 16~23S rRNA, the $VITEK^{(R)}$ 2 system (an automated microbial identification system) and matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS). A. baumannii isolates (74.8%, 92/123) were the most common species, A. nosocomialis (10.6%, 13/123) and A. pittii isolates (7.5%, 9/123) were second and third most common strains of the A. calcoaceticus-A. baumannii (ACB) complex, respectively. A. soli (5.0%, 6/123) was the most common species of the non-ACB complex. RpoB gene sequencing and ARDRA of the ITS region were demonstrated to lead to more accurate species identification than the other methods of analysis used in this study. These results suggest that the use of rpoB genotyping and ARDRA of the ITS region is useful for the species-level identification of Acinetobacter isolates.

• TTA 저널
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• 통권129호
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• pp.123-125
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• 2010

• 한국가스학회:학술대회논문집
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• 한국가스학회 2004년도 추계학술발표회 논문집
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• pp.123-129
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• 2004

• 대한기계학회논문집B
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• 제22권7호
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• pp.980-991
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• 1998

In this study, nucleate pool boiling heat transfer coefficients of alternative refrigerants on a plain, low fin, and two enhanced tubes were measured and compared against each other. To obtain data at conditions similar to the actual evaporator, a fluid heating method was employed instead of an electric heating method in the experiments. R123, R134a, R22 and R410a were used as working fluids and data were taken at 7 deg.C ar heat fluxes of 20 ~ 100 kW/m$\^$2/. Comparison of the plain tube data against some correlations showed that the simplest correlation of Cooper based on reduced pressure predicted the data for all fluids tested with a 10% deviation. For all refrigerants, enhanced tubes composed of subsurface and subtunnels, especially Thermoexcel-E tube, showed the highest heat transfer coefficients among the tubes tested with one exception that the low fin tube's performance was better than those of enhanced tubes for high vapor pressure fluid such as R410a at high heat flux. Finally, a low fin and enhanced tubes showed higher heat transfer enhancement for low vapor pressure of R123 than for high vapor pressure fluisd. For R123, the enhancement factors for Turbo-B and Thermoexcel-E tubes were 2.8 ~ 4.8 and 4.6 ~ 8.1 respectively.

• Journal of Advanced Marine Engineering and Technology
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• 제36권1호
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• pp.64-71
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• 2012

An efficient cooling system is an essential part of the electronic packaging such as a high-luminance LED lighting. A special technology, Pulsating Heat Pipe (PHP), can be applied to improve cooling of a sealed, explosion-proof LED light fixture. In this paper, the characteristics of the pulsating heat pipes in the imposed thermal boundary conditions of LED lightings were experimentally investigated and a PHP device that works free of alignment angle was investigated for cooling of explosion-proof LED lights. Five working fluids of ethanol, FC-72, R-123, water, and acetone were chosen for comparison. The experimental pulsating heat pipe was made of copper tubes of internal diameter of 2.1 mm, 26 turns. A variable heat source of electric heater and an array of cooling fins were attached to the pulsating heat pipe. For the alignment of the heating part at bottom, an optimum charging ratio (liquid fluid volume to total volume) was about 50% for most of the fluids and water showed the highest heat transfer performance. For the alignment of the heating part on top, however, only R-123 worked in an un-looped construction. This unique advantage of R-123 is attributed to its high vapor pressure gradient. Applying these findings, a cooling device for an explosion-proof type of LED light rated 30 W was constructed and tested successfully.

• 대한기계학회논문집B
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• 제27권8호
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• pp.1033-1041
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• 2003

Two-phase flow pattern data during horizontal in-tube flow boiling are presented for pure and mixed refrigerants of R134a and Rl23, The flow pattern is observed through tubular sight glasses located at inlet and outlet of the test section, which is made of a stainless steel tube, 2m long with 10mm I.D., 1.5mm wall thickness. The obtained results are compared with the available various correlations for flow pattern. The flow pattern map of Hashizume was in good agreement with the present data except the region of low mass velocity. Weisman flow pattern map was also known to satisfactorily predict data for refrigerants in the region of annular flow. In this study, the flow pattern are simply classified into two groups; stratified(including intermittent, stratified and stratified-wavy) flow and annular flow. The transition quality from stratified to annular flow was obtained by modifying the liquid Froude number.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2005년도 춘계학술대회
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• pp.123-127
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• 2005

This paper considers a set of project management practices for government R&D projects, enterprise R&D projects and new product design project. The approach of managing multi-project is proposed by the use of organizational structure and control.