• 한국전산유체공학회:학술대회논문집
• /
• 2005.04a
• /
• pp.75-78
• /
• 2005

A numerical investigation has been performed to discuss the radiation-affected steady-laminar natural convection in an enclosure under a large temperature difference. Due to inherent nature of this study, the Boussinesq approximation is no longer valid. Therefore the radiating fluid in an enclosure is treated as a ideal gas. To examine the effects of thermal radiation on thermo-fluid dynamic behaviors in complex geometries, two incomplete partitions are introduced. Based on the results of this study, the dispositions of incomplete partitions with radiatively participating medium are found to incur a distinct difference in fluid-dynamic as well as thermal behavior.

• 한국전산유체공학회:학술대회논문집
• /
• 2005.04a
• /
• pp.173-181
• /
• 2005

A fluid transient analysis for the propellant flow in a monopropellant propulsion system is conducted using the method of characteristics (MOC). Algebraic simultaneous equations method and Clamor's rule method utilized to drive the compatible and characteristic equations are reviewed to understand MOC more extensively. The identification of fluid transient phenomena of propulsion system of Koreasat 1 is carried out through parametric studies. Also this work describes the reason that the propulsion system of Koreasat 1 has no orifice to control flow transients or to limit the initial hydrazine flow rate for the first-pulse firing.

• Journal of computational fluids engineering
• /
• v.11 no.1 s.32
• /
• pp.43-51
• /
• 2006

A fluid transient analysis on the Koreasat 1 & 2 pipeline system is conducted through numerical parametric studies in which unsteady friction results are compared with quasi-steady friction results and show relatively accurate prediction of the response curve with the unsteady friction. The code developed and used in this analysis has finished verification through comparing with the original Zielke model, the full and recursive convolution model and quasi-steady model as a reference. The unsteady friction is calculated by the recursive convolution Zielke model in which a complete evolution history of velocity field is no longer required so that it makes the fluid transient analysis on the complicated system possible. The results show that the application of quasi-steady friction to model cannot predict the entire response curve properly except the first peak amplitude but the application of unsteady friction to model can predict reasonably the response curve, therefore it is to know the characteristics of the propulsion system.

• Journal of Korea Association of Health Promotion
• /
• v.1 no.1
• /
• pp.26-32
• /
• 2003

The current status and future prospects of parasitic infections in Korea is briefly reviewed. Soil-transmitted helminth infections including ascariasis, trichuriasis, and hookworm infections decreased remarkably. owing to the national control activities excuted by the Korea Association of Health Promotion(formerly Korea Association of parasite Eradication) using mass heath education. Important recent trends include reemergence of vivax malaria since 1993, persistence of food-borne trematode infections including clonorchiasis and intestinal trematode infections, increased detection of zoonotic parasitosis, close-up of infection with opportunistic parasites including cryptosporidiosis, toxoplasmosis, and pneumosytosis, increase of imported tropical infectious disease, appearance of new parasitic disease such as gymnophalloidiasis, and increase of accidental infections with free-living amoebae. These trends represent greatly changed overall patterns of parasitic infections in Korea.

• Journal of computational fluids engineering
• /
• v.10 no.2
• /
• pp.69-81
• /
• 2005

A fluid transient analysis for the propellant flow in a monopropellant propulsion system is conducted by using the method of characteristics(MOC). It reviews algebraic simultaneous equations method and Cramer's rule method utilized to drive the compatible and characteristic equations to understand MOC extensively. The identification of fluid transient phenomena of propulsion system of Koreasat 1 is carried out through parametric studies. The valve response time is one of the dominant parameters governing the fluid transient phenomena. The results show that the shorter closing time induces the greater pressure response amplitude. And it shows that the installation of in-line orifice is effectively to limit the fluid transients in rapid valve response time and at high pressure. But it seems that the effect of orifice weakens at slow valve response time and at low pressures.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 1996.05a
• /
• pp.295-298
• /
• 1996

In this study, we have fabricated all solid state electrochromic devices using WO$_3$ film as the working electrode, V$_2$O$\_$5/ film as the counter electrode and PEO-LiClO$_4$-PC film as the solid electrolyte. The WO$_3$ thin films for working electrode and V$_2$O$\_$5/ thin films for counter electrode were deposited onto ITO glass by vacuum evaporation and were shown good electrochromic and state properties after 1x10$\^$5/ cycles. PEO-LiClO$_4$-PC polymer electrolyte can easily be formed into thin films, do not absorb in the visible region of the light. Therefore, such electrolyte have electrochromic properties suitable for large-scale all solid-state electrochromic devices. All solid-staeelectrochromic devices fabricated in this polymer electrolyte have optical modulation of 20%∼30% at 1.5 V.

• Parasites, Hosts and Diseases
• /
• v.35 no.3
• /
• pp.215-218
• /
• 1997

An unusual over-gravid female of Enterobiw uemiculcris was recovered from a 15-month old child by cello-tape anal swab. The patient resided in Inchon and complained of severe anal itching. The worm measured 7.8 mm in length and 0.5 mm in width, and retained typical morphologic features of E. uemiculnris such as cephalic alas and a sharply pointed posterior end. In this gravid female, peculiarly. the uterus was tremendously distended, and about 99% of the whole body length was completely packed with a great number of eggs. Other internal organs were difficult to observe. This paper describes a peculiar over-gravid female of E. vemiculcyis.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2004.05b
• /
• pp.1262-1266
• /
• 2004

The current combining of computer and geographic information technology. The result of such research oil determinate objective factors of hydrologic-topographical parameters through joining hydrology and GIS(Geographic Information System). In this study, we wish to offer the base data to determinate hydrologic-topographical parameters request of runoff model analysis in this basin. First, we computed the CN(curve number) by using GIS, and then classify the digital map of soil group and landuse on the Sulma river basin. Second, we used Avenue Script to calculate the height of efficient GIS work before using the Clark model to work out flood runoff flow.

• Journal of The Korean Society of Inherited Metabolic disease
• /
• v.14 no.2
• /
• pp.182-185
• /
• 2014

GM1 gangliosidosis is a rare autosomal recessively inherited metabolic disease due to deficiency of ${\beta}$-galactosidase caused by mutations in the GLB1 gene. There have been three clinical subgroups in GM1 gangliosidosis, however it is difficult to differentiate because there is considerable overlap between classical phenotypes and clinical and imaging findings among the subgroups. Here, we report a Korean girl with type 2 GM1 gangliosidosis, who showed dysostosis multiplex and progressive neurological deterioration. Developmental regression was first noted at the age of 9 months, and she was diagnosed as GM1 gangliosidosis by ${\beta}$-galactosidase enzyme analysis and GLB1 mutation analysis at the age of 16 months.

• Journal of Korean Society for Atmospheric Environment
• /
• v.16 no.6
• /
• pp.665-674
• /
• 2000

A major source of the hazardous waste generated is from chemical industries producing plastics, herbicides, pesticides and chlorinated solvents. All of these processes produce a class if hazardous waste termed the chlorinated hydrocarbons(CHCs), either directly or from undesirable side reactions. In this study, we investigated the destruction characteristics of hazardous waste through incineration. A nonequilibrium combustion model was used to describe the effect of the chemical kinetics due to the flame inhibition characteristics of $CCl_4$ which was used as the surrogate of hazardous waste. A parametric screening studies was made in a dump incinerator proposed in this study. The dump incinerator showed high $CCl_4$ DRE(Destruction and Removal Efficiency) as 5 nines. $CCl_4$/CH$_4$ ratio appeared to be most important in the destruction of $CCl_4$ through incineration.