• Journal of the Korean Society of Tobacco Science
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• v.26 no.2 s.52
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• pp.152-158
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• 2004

Among short-term in vitro genotoxicity assays, micronucleus assays are rapid, inexpensive, and less labor-intensive system. We have undertaken a comparative study of sensitivity of cigarette smoke condensate(CSC) by general micronucleus(MN) assay and cytokinesis-block micronucleus(CBMN) assay. In this study, V79 Chinese hamster cells were employed to evaluate and compare the genotoxicity of CSC of Kentucky Reference Cigarette 2R4F by 2 kinds of in vitro MN assay methods. To determine the optimum concentration of cytochalasin B(CYB) to obtain the maximal number of binucleated cells for CBMN assay, triplicate cultures of growing cells were treated with CYB for 15 h. CYB treatments caused a concentration-dependent increase in cytotoxicity($1\~4{\mu}g/mL$) and proportion($0.25\~1\;{\mu}g/mL$) of binucleated cells. These data suggested that 1 ug/mL of CYB is as an optimum dose for CBMN assay in binucleated V79 cells. Short treatment(4 h) of CSC induced a micronucleated cells with a concentration-dependent response in the presence or absence of CYB, but CSC-induced MNs were weakened when S9 was present. Long treatments(19 h) of CSC also induced a significant increase MN formation with a concentration-dependent response. At a concentration of 75 ${mu}g/mL$, the MN cell frequencies of general MN assay and CBMN assay were $6.5\%\;and\;11.7\%$, respectively. Linear regression analysis revealed a good correlation in CBMN assay between a concentration of CSC and MN cell frequency. All these data indicated that CBMN assay is more sensitive to the induction CSC-induced MN than general MN assay.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.6
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• pp.23-29
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• 2003

Transonic two-phase flow of Saturated humid air, in which relative humidity is 100%, with various condensation processes around thin airfoils is investigated. The study uses an extended transonic small-disturbance(TSD) model of Rusak and Lee [11, 12] which includes effects of heat addition to the flow due to condensation. Two possible limit types of condensation processes are considered. In the nonequilibrium and homogeneous process, the condensate mass fraction is calculated according to classical nucleation and droplet growth rate models. In the equilibrium process, the condensate mass fraction is calculated by assuming an isentropic process. The flow and condensation equations are solved numerical1y by iterative computations. Results under same upstream conditions describe the flow structure, field of condensate, and pressure distribution on airfoil's surfaces. It is found that flow characteristics, such as position and strength of shock waves and airfoil’s pressure distribution, are different for the two condensation processes. Yet, in each case, heat addition as a result of condensation causes significant changes in flow behavior and affects the aerodynamic performance of airfoils.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.1
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• pp.693-699
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• 2016

The simulators for pump operation developed by domestic or overseas research have been developed for dynamic analysis or operator training purposes. However, previous developed simulators focused on the operators so they are unsuitable for logic designers or commissioning engineers who need to change the operation conditions or logics arbitrarily. In addition, the simulator for two or more condensate pumps' operation, which can be used easily by plant designers or operators, has not been developed. Accordingly, this paper suggests a simulation method that can be used easily for plant designers or operators using MATLAB Simulink. This suggestion helps users who can use MATLAB to implement ANSI/ISA S5.2, which is applied mainly for DCS (Distributed Control System). In addition, to implement the logics specified in the CODE, Sub-Systems were created for the block and evaluated to determine if they can be used in the simulator. In the working level stage using the suggested method, all error possibilities that might occur during the three pumps' rotation operation could be verified with the suggested simulator during the design stage or before operation.

• Journal of the Korean Society of Tobacco Science
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• v.12 no.1
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• pp.3-7
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• 1990

Cigarette smoke is an aerosol consisted of both vapor and Particulate phases. In this study, the smoke condensates from several blended cigarettes were dissolved in water and the pH of the resulting solution was determined. The pH of the smoke condensate decreased with increase of puff number. In the beginning the pH decreased a little, while decreased remarkably from puff No.5 to puff No.10.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1998.04a
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• pp.148-153
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• 1998

A resonance is the one of major reasons of vibration problems occurred in industrial fields. To reduce vibration level due to resonance, structure reinforcements or change of the dynamic characteristics is generally applied. In this paper, the troublesome vibration levels of the motor shaft and auxiliary condensate pump are reduced by avoiding resonance.

• Bulletin of the Korean Mathematical Society
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• v.50 no.5
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• pp.1441-1450
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• 2013

In this paper, we consider two-component Bose-Einstein condensates with an internal atomic Josephson junction in the general case, i.e., 0 < p < $\frac{2}{(d-2)^+}$. We prove existence and uniqueness results for the ground states, and obtain some properties of the ground states with large parameters.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2002.05a
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• pp.29-34
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• 2002

As the makeup water entering the boiler feed water cycle usually contains corrosive gases, particularly oxygen and carbon dioxide, so the corrosive gases should be eliminated by a deaerator. While the other domestic companies have made a deaerator for land industrial field, our company has developed and is able to produce a spray & scrubber type deaerator for marine to maintain below the level of 7ppb of dissolved oxygen in the condensate. In this paper, we describe the principle, design technique and experimntal results of the spray & scrubber type deaerator.

• 한국약용작물학회:학술대회논문집
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• 2010.10a
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• pp.420-421
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• 2010

• 한국약용작물학회:학술대회논문집
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• 2010.10a
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• pp.404-405
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• 2010

• 월간 기계설비
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• s.290
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• pp.53-59
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• 2014

SK이노베이션이 발주한 V-PROJECT는 이미 가동중인 SK에너지 인천COMPLEX 석유화학플랜트 기존 공장에 Condensate와 Crude를 처리하여 Benzene과 p-Xylene 생산시설 및 부대시설 증설 프로젝트이다. 이 시설에서 주로 생산되는 자일렌(p-Xylene)은 폴리에스터 섬유의 원료로서 국내를 비롯하여 중국, 인도, 남미 등의 섬유시장 성장으로 최근들어 수요가 많아짐에 따라 생산시설을 증설한 것이다. 이 프로젝트 완공으로 2015년부터는 기존보다 3배 증가한 벤젠 50만톤, 톨루엔 10만톤, 자일렌 130만톤이 연간 생산될 예정이다. 본지는 V4 Area의 기계설치 및 배관 철골제작 설치, 도장공사를 시공한 성창E&C(주)(대표 김기영)의 이종윤 소장을 만나 플랜트 현장 특성 상 기밀사항인 시공은 생략하고 현장 이야기를 들어 보았다.