• 한국가시화정보학회:학술대회논문집
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• 2005.12a
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• pp.28-35
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• 2005

Experiments were conducted to show the characteristics of the flow on triple parallel plane impinging jets. Measurements of mean velocity components and turbulent intensities were carried out with a particle image velocimetry(PIV) to investigate the flow field generated by the air issued from three identical plane parallel nozzles and mixed with the ambient air. The measurements range of these experiments were Reynolds number of 5000 and 1000 based on the nozzle width and the case of nozzle-to-plate distances were two times, six times and ten times the width of the nozzle. Results show that recirculation region of Re=5000 is the stronger than that of Re=1000. Therefore, velocity loss of centerline for Re=5000 that shows strongly recirculation region takes effect greatly.

• Journal of the Korean Mathematical Society
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• v.51 no.1
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• pp.1-15
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• 2014

A conditional version of the classical central limit theorem is derived rigorously by using conditional characteristic functions, and a more general version of conditional central limit theorem for the case of conditionally independent but not necessarily conditionally identically distributed random variables is established. These are done anticipating that the field of conditional limit theory will prove to be of significant applicability.

• Korea-Australia Rheology Journal
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• v.14 no.4
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• pp.203-207
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• 2002

Particle-particle interaction is of great importance in the study of suspension rheology. In this research we have investigated the hydrodynamic interaction between two identical cylinders in viscoelastic fluids numerically as a model problem for the study of viscoelastic suspension. We confine two neutrally buoyant cylinders between two parallel plates and impose a shear flow. We determine the migration velocity of two cylinders. The result shows that cylinders move toward or away from each other depending upon the initial distance between them and that there is an equilibrium distance between two cylinders in viscoelastic fluids regardless of the initial distance. In the case of Newtonian fluid, there is no relative movement as expected. The results partly explain the chaining phenomena of spherical particles in shear flows of viscoelastic fluids.

• East Asian Economic Review
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• v.21 no.4
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• pp.295-315
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• 2017

This paper derives the gravity equation with intermediate goods trade. We extend a standard monopolistic competition model to incorporate intermediate goods trade, and show that the gravity equation with intermediates trade is identical to the one without it except in that gross output should be used as the output measure instead of value added. We also show that the output elasticity of trade is significantly underestimated when value added is used as the output measure. This implies that with the conventional gravity equation, the contribution of output growth can be substantially underestimated and the role of trade costs reduction can be exaggerated in explaining trade expansion, as we demonstrate for the case of Korea's trade growth between 1995 and 2007.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.477-480
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• 2007

Hydrate phase equilibrium for the binary CO2+water and CH4+water mixtures in silica gel pore of nominal 6, 30, and 100 nm were measured and compared with the cacluated results based on van der Waals and Platteeuw model. At a specific temperature three-phase hydrate-water-vapor (HLV) equilibrium curves for pore hydrates were shifted to the higher-pressure condition depending on pore sizes when compared with those of bulk hydrates. Notably, hydrate phase equilibria for the case of 100 nominal urn pore size were nealy identical with those of bulk hydrates. The activities of water in porous silica gels were modified to account for capillary effect, and the calculation results were generally in good agreement with the experimental data.

• Management Science and Financial Engineering
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• v.11 no.2
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• pp.61-84
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• 2005

This paper considers a special case of the two-dimensional bin-packing problem for identical items. The objective of this work is to maximize the space utilization. The main contribution of the paper is to suggest a new heuristic algorithm keeping in view the existing complexity of racking system for the footwear boxes in the compartments of different sizes for a warehouse. The results show that a significant improvement can be obtained. An economic choice of compartments is also estimated using the criteria for maximizing space utilization. A non-linear mathematical model was presented based on the constraints of racking dynamics.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.21 no.48
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• pp.233-240
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• 1998

Recently, Hong-Jun Kim et al. introduced an improved process incapability index $C^*_{psk}$ by the transformation of the $C_{psk}{\;}C^*_{psk}$. A simple transformation of $C_{psk}$, can be regard as a process incapability index, provides an uncontaminated separation between information concerning the process accuracy and precision while this kind of information separation is not available with the $C_{psk}$. By an identical conception, in this article a new process incapability index $C^*_{psk}$ for Non-Normal process can be proposed by the transformation of the process capability index $C^*_{psk}$. The motivation behind introduction of $C^*_{psk}$ is that process capability index $C^*_{psk}$ cannot give information of the process accuracy and precision. A significant result of this research that $C^*_{psk}$ for the case where the target value T is equal to the midpoint of the specification limits or not Is evaluated without respect to T. Accordingly, $C^*_({psk})$ will be propose a reasonable process incapability measure for Non-Normal process

• Archives of Pharmacal Research
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• v.14 no.2
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• pp.118-123
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• 1991

Potentially dangerous nitrosamines have been shown to result from the reaction of sodium nitrogusside with several drugs under physiological conditions (pH 7.3 and $37^\circ{C})$. In each case the products were identical to those produced upon reaction with nitrous acid at much lower pH values. Reaction rates were shown to reflect a first order dependence on both amine and nitroprusside concentrations and to increase at higher pH values, approximately in proportion to concentrations of unprotonated amine. Fast reactions of sodium nitroprusside with reduced glutathione, cysteine, and ascorbate suppress but do not prevent the conversion of amines into N-nitrosamines. These results show sodium nitroprusside to be very potent nitrosating agent under physiological conditions and suggested nitrosamines may be formed during its normal pharmacological administration.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.97.3-97
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• 2002

This paper presents the vibration characteristics of an intelligent cantilever beam in contact with a fluid using a PZT actuator and PVDF film. The dynamic behaviors of a flexible beam-water interaction system are examined. The effect of the liquid level on free vibration of the composite beam in a partially liquid-filled circular cylinder is investigated. The coupled system is subject to an undisturbed boundary condition in the fluid domain. It was found that the coupled natural frequencies decreased with the fluid level for the identical composite beam due to added mass effect. In case of the free-free boundary condition, the natural frequency gently decreased at fluid water level betw...

• Journal of Mechanical Science and Technology
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• v.17 no.9
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• pp.1297-1315
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• 2003

This study deals with the free vibration of two identical circular plates coupled with a bounded or unbounded fluid. An analytical method based on the finite Fourier-Bessel series expansion and Rayleigh-Ritz method is suggested. The proposed method is verified by the finite element analysis using commercial program with a good accuracy The case of bounded or unbounded fluid is studied for the effect on the vibration characteristics of two circular plates. Also, the effect of gap between the plates on the fluid-coupled natural frequencies is investigated.