• 천문학회지
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• 제34권3호
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• pp.143-147
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• 2001

UBVI CCD photometry of open cluster NGC 2324 is presented. C-M diagrams of this cluster show well-defined main sequence with a red giant clump centered at B - V =1.05, V =13.45. We derived the major cluster characteristics; E(B - V)=0.17$\pm$0.12 from color-color diagram and mean color of red giant clump stars, (m - M)o=13.1$\pm$0.1 from zero age main sequence fitting, and [Fe/H]$\~$-0.32 from comparison the theoretical model developed by Bertelli et al. (1994) to the observed C-M diagrams. We estimate the age of NGC 2324 to be log t$\~$8.8 by applying isochrone fitting and morphological age index method.

• 한국해양학회지
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• 제30권6호
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• pp.529-536
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• 1995

1994년 5월 대한해협 서수로 표층에서 초미세식물플랑크톤을 분리, 배양하였다. 0.2${\sim}$2.0 ${\mu}m$ 범위에서 여과분리 및 희석법으로 단일종으로 분리하여 f/2 배양액으로 배양하였다. 개체의 외형은 구형이었고 지름은 2 ${\mu}m$ 내외였으며, 배양된 개체군은 황록색을 보여주었다. 표면은 매끈하였고 세포벽으로 싸여진 세포에서 핵, 엽록체, 미토콘드리아, 골기체, 액포 등이 확인되었다. 분리된 종은 엽록소 a와 b를 갖는 색소 구성과 세포막, 틸라코이드막구성, 피레노이드 등을 포함하는 미세구조 특성으로 볼 때 녹조류에 속하는 클로렐라의 일종으로 보인다.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2006년도 High Temperature Superconductivity Vol.XVI
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• pp.32-32
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• 2006

• 한국해양공학회지
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• 제23권6호
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• pp.131-135
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• 2009

We present an optimum design method for a rectangular reinforced concrete beam using Genetic Algorithms. The optimum design procedure in this paper employs 2 design cases: i) all of the design variables (b, d, As) of the rectangular reinforced concrete section are used pseudo-continuously, ii) one is pseudo-continuous for the concrete cross section (b, d) and the other is discrete, using an index for the steel area (As). The optimum design in this paper uses Chakrabarty's model. In this paper, the Genetic Algorithms use the method of Elitism and penalty parameters to improve the fitness in the reproduction process, which leads to very practical designs. The optimum design of the steel area in the examples uses ASTM standard reinforcing bars (#3~#11, #14, #18).

• 대한기계학회논문집B
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• 제27권11호
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• pp.1604-1611
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• 2003

The experimental investigation of a coal splitter used in the 500㎿(e) boilers of fossil power plant is carried out to validate the design criteria. To predict air flow and the amount of particles at the exit, velocity and the weight of particles are measured on test planes using the coal splitter model with two-dimensional phase doppler particle analyzer and the glass fiber filter. It is found that the position of guide plate influences significantly both flow rates of gas and particle at the exit. Gas flow rate was a linear function of the guide plate, whereas particle flow rate was a exponential function of it.

• 한국음향학회지
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• 제12권5호
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• pp.47-53
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• 1993

능동소음제어를 위하여 수렴속도가 빠르면서 정상상태오차를 최소화하는 오차보상 NLMS 알고리듬인 CNLMS 알고리듬을 제안하였다. 이 CNLMS 알고리듬에서는 수렴속도를 빠르게 하기 위하여 입력소음과 오차소음의 전력에 따라 수렴인자를 가변시킨 NLMS 알고리듬을 사용하였다. 도한 정상상태오차를 최소화하기 위하여 소음발생기를 사용하지 않고 오차경로에서 발생하는 소음오차를 더욱 작아지도록 보상하는 보조시스템을 사용하여 안정된 능동소음제어가 되도록 하였다. 이와 같은 시스템의 성능을 기존의 적응디지틀필터인 LMS 및 NLMS 알고리듬을 이용한 필터의 그 성능과 비교하였다. 각 알고리듬에 대한 시뮬레이션을 행한 결과, 제안한 CNLMS 알고리듬의 소음레벨은 LMS 및 NLMS 알고리듬의 것보다 각각 평균 14dB 및 6dB 정도 더 큰 감쇄효과가 있음을 확인하였다.

• 대한약리학회지
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• 제8권1호
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• pp.59-62
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• 1972

This study was undertaken to observe the effect of xanthine such as caffeine and aminophylline on the activity of carbonic anhydrase in the kidney and stomach of the mouse. Carbonic anhydrase activities were measured by Philpot & Philpot method (1936). The results of this experiment were as follows: 1. The activity of carbonic anhydrase in the kidney of the mouse was silightly inhibited by the administration of caffeine (0.1 mg/gm, B.W.) or aminophylline (0.08 mg/gm, B.W.). The inhibition was more pronounced by the administration of aminophylline than that of caffeine. 2. In the stomach, there was no significant change in the activity of the carbonic anhydrase after the administration of either caffeine or aminophylline.

• 산업경영시스템학회지
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• 제37권3호
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• pp.113-121
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• 2014

This paper considers a scheduling problem in a two-machine flowshop with outsourcing strategy incorporated. The jobs can be either processed in the first machine or outsourced to outside subcontractors. This paper wants to determine which jobs to be processed in-house and which jobs to be outsourced. If any job is decided to be outsourced, then an additional outsourcing cost is charged The objective of this paper is to minimize the sum of scheduling cost and outsourcing cost under a budget constraint. At first this paper characterizes some solution properties, and then it derives solution procedure including DP (Dynamic Programming) and B&B (Branch-and-Bound) algorithms and a greedy-type heuristic. Finally the performance of the algorithms are evaluated with some numerical tests.

• Nuclear Engineering and Technology
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• 제30권1호
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• pp.26-39
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• 1998

The containment pressure and temperature transient analysis computer code CONTEMPT4/MOD5 is modified to incorporate the passive containment cooling models. The correlations are selected from the existing experimental heat transfer correlations to model the natural and mixed convection in annular space between the containment shell and the shield building. The evaporative heat transfer of the water film on the outer shell of the containment is modeled using the correlations derived from the analogy between the heat and mass transfer. The modified code is applied to the Ap600 containment transient analysis for the model verification and the results are compared to the results of GOTHIC calculation done by Westinghouse. Also, d series of parametric sensitivity studies of heat transfer correlations, water film ratio and delay time of the wet cooling on the containment peak pressure and temperature following LOCA are performed for the containment of 1000MWe passive plant, KP1000.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제55권5호
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• pp.258-264
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• 2006

This paper presents an integrative control scheme for series-type active power filters combined with shunt passive filters not only to compensate for the source voltage unbalance and current harmonics but also to correct the power factor. To reduce the power capacity of the active filters, passive filters are connected in parallel. Diode rectifiers are replaced by the PWM converters in order to feed the real power back to the source. Power factor control is performed by changing the phase of the load voltage so that the phase of the source current coincides with that of the source voltage. The resultant voltage reference is the addition of the voltage component compensating for the source voltage unbalance and harmonic currents and the voltage component correcting the power factor. The validity of the proposed algorithm has been verified by experimental results.