• 한국전산유체공학회:학술대회논문집
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• 1997.10a
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• pp.113-119
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• 1997

This paper addresses to the injection pressure effect on the diesel spray. The injection pressure is varied from 10MPa, in general system, upto 200MPa, in high pressured system in order to understand the effect. The gas phase is modelled in terms of the Eulerian continuum conservation equations of mass, momentum, energy and fuel vapour fraction. The liquid phase is modelled following the discrete droplet model approach in Lagrangian form. The droplet distributions, vapor fractions and gas flows are analyzed in various injection pressure cases.

• Proceedings of the KIEE Conference
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• 1997.07c
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• pp.917-919
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• 1997

Recently, electric industry confront a strategical change and high competiveness environment in the course of deregulation. Especially, rapid growth in electricity demand, financial need for new power plant construction, and environmental problems have led to search for more efficient energy production and energy conservation technologies in Korea. Due to the potential energy and cost savings, DSM(Demand-Side Management) plays and important role in the electric resource planning. In this paper, we suggest DSM potential evaluation procedures and algorithm. Also, we present screening analysis methods for DSM potential evaluation.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2000.10a
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• pp.557-562
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• 2000

Estuary lakes constructed for agricultural water resources development projects have encountered eutrophication problems. Natural water purification function of wetland is considered for nutrient removal from inflowing stream. A constructed wetland was designed and installed for pollutant loading abatement in estuary lake Koheung. Combined pond-wetland system was adopted. In this system primary and secondary ponds and six wetland cells were interconnected. Reed and cattail were selected for wetland vegetation and planted in the wetland cells. In this paper, design criteria of the pond-wetland system in temperate weather zone is presented.

• Journal of the Korean Society for Railway
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• v.6 no.3
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• pp.174-178
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• 2003

This paper presents the development of 2-dimensional discrete element algorithm to generate circle and line elements for the simulation of the ballast and sleeper in railway. An example of randomly distributed circle elements show a good applicability of this algorithm for the modeling of the behaviors of ballast. The output about unbalaned force, particle velocity, and total energy conservation from the code is evaluated to check if the calculation is conducted properly.

• 한국전산유체공학회:학술대회논문집
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• 2002.10a
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• pp.17-22
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• 2002

A numerical solution procedure has been developed to analyze the flow field resulted from the injection of a transverse jet through the divergent flap of a 2DCD nozzle for thrust vector control. The formulation employs the compressible Navier-Stokes equations in conservation law form and a two equation $\kappa-\omega$ turbulence model. Detailed numerical results are presented in this paper for the 2DCD nozzle over a range of secondary to primary injection mass flow ratios and nozzle pressure ratios.

• Proceedings of the Optical Society of Korea Conference
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• 2008.07a
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• pp.429-430
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• 2008

This paper presents a new approximation for the crystalline lens of the human eye with refracting surfaces based on Gullstrand-Emsley schematic eye during accommodation. A new model eye describes the isoindical profiles in the form of symmetric spherical surfaces. A vary important condition which was imposed upon the parameters (thickness, radius) was the lens volume conservation during accommodation.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 1998.09a
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• pp.130-133
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• 1998

This paper identifies diffraction-induced wave setup when waves enter into a harbor of constant depth through a breakwater gap narrower than one wave length. It is well known, for this case, that the waves in the lee of the breakwater propagate as if from a point source and the wave crest lines are approximated well by semicircular arcs. Wave height decreases in accordance with conservation of energy; thereby resulting in an appreciable setup of the surface. (omitted)

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.719-725
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• 2000

In order to save the energy and to protest environmental conservation, a evaporation type of PTC heater was developed as a Part of replacement in automobile industry. The honeycomb type of PTC heater made by Texas Instrument draw a much attention for this purpose. Especially this paper will describe the general and characterize the typical electrical properties of PTC heater for the application of automobile in detail.

• 보존과학연구
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• s.16
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• pp.139-154
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• 1995

In this paper the fundamental elements relevant to schematic daylighting design for museum are discussed and suggested. The illuminance difference between outdoor and exhibition space in consideration of the constraints necessary for the conservation of artifacts can be solved by conversion into Luminance. Also it is considered that transition zone in two stages should be provided for adaption before entering exhibition space and overall luminance within the visual field along viewing circulation should be balanced including the apertures designed for introducing the daylight or visual linking.

• Journal of Korean Society for Quality Management
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• v.14 no.2
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• pp.33-39
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• 1986

This paper is to present basic concepts of availability, irreversibility, dead states, its relationship to other thermodynamic functions, and the history of availability. The balance of availability and effectiveness has also been formulated in order to build basis on which further study and actual application of availability in estimation of available energy are to be thought.