• Proceedings of the Korean Vacuum Society Conference
• /
• 1997.07a
• /
• pp.93-93
• /
• 1997

• Proceedings of the Korean Vacuum Society Conference
• /
• 1992.02a
• /
• pp.37-38
• /
• 1992

• Proceedings of the Korean Vacuum Society Conference
• /
• 2008.02a
• /
• pp.270-270
• /
• 2008

• Journal of the Korean Vacuum Society
• /
• v.16 no.6
• /
• pp.405-413
• /
• 2007

Effect of design factors on the performance of vacuum system was simulated for optimum design of system. In this investigation, the feasibility of modelling mechanism for $VacSim^{Multi}$ simulator was proposed. Simulation results of pumping design factor showed the possibilities of simulation fore-study for the detailed design factors. Simulation of roughing pump presented the expected pumping behaviors based on the specifications of commercial pump. Application of booster pump exhibited the high pumping efficiency for middle vacuum range. Combinations of optimum backing pump for diffusion and turbo vacuum system were obtained. And, the characteristics of process application of both systems were also acquired.

• Food Science and Preservation
• /
• v.6 no.3
• /
• pp.324-327
• /
• 1999

This study was carried out to establish the extraction method of red ginseng extract without saponin decomposition. Red ginseng was extracted with impulse vacuum system and multi-stage extraction method. Crude saponin content of red ginseng extract (RGE) from impulse vacuum system was 5.4-5.9%, while that of RGE from multi-stage extraction method was 8.2-8.3%. However, HPLC Patterns indicated that saponins of RGE from impulse vacuum system were hardly decomposed, while those of RGE from multi-stage extraction method were decomposed, especially in ginsenoside -Rgl and -Re saponin. Also, the yields of red ginseng by impulse vacuum system were 15 to 20 times higher than that of multi-stage extraction method.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.33 no.11
• /
• pp.886-893
• /
• 2009

To develop glass panel vacuum lift system for the post process in module line of FPD(Flat panel display) such as LCD and PDP, new vacuum adsorption parts of this system are proposed. These parts are composed of variable geometry configurations utilizing ceramic porous medium for variable size of glass panels. In order to design this device, detail understanding of flow phenomena in the flow path of vacuum adsorption system is essential. Thus, CFD analysis and designs are performed for several configurations in terms of pressure drop and balancing force at the adsorption side. From the result, new configuration is recommended for optimum design and manufacturing purpose.

• Journal of the Korean Society for Precision Engineering
• /
• v.26 no.3
• /
• pp.88-97
• /
• 2009

The vacuum die casting techniques can diminish the porosity of products and provide better surface appearance by the ordinary high pressure die casting process. The vacuum system can also reduce the cold laps in the die casting process and minimize the overflow pockets of the die. The vacuum system does not need high pressures to die cast compared to the ordinary die casting process, and so enables die casting of large parts for a given machine size. Parts made by the vacuum system have higher strength and more elongation than parts made by the ordinary die casting systems. In this paper, we designed and produced the Magnesium seat frames using the vacuum die casting processes. The new Magnesium seat frame was designed to satisfy safety regulations. Some safety test procedures of the seat frame were simulated by the finite element method. We obtained 10% weight reduction by design modification of seat frames compared to the current model. Flow simulations were carried out to minimize the trial and error in producing the parts. The die casted parts using vacuum systems resulted in better mechanical characteristics and no defects compared to those without vacuum systems.

• Journal of the Korean Vacuum Society
• /
• v.2 no.2
• /
• pp.139-144
• /
• 1993

The dynamic calibration system which can calibrate the ultrahigh vacuum pressure down to $10^{-10}$torr has been fabricated. The production and control of minute flow of $10^{-6}~10^{-9}$torr L/s range is done by a porous plug connected to the high vacuum standards system. The base pressure of the UHV standards system down to $10^{-11}$torr range was obtained by refrigerator type cryopump, whose pumping speed is known to be constant. By using the UHV standards system, 2 extractor gauges and 1 nude ion gauge were calibrated and their linearities and scatterings were studied.

• Journal of Ginseng Research
• /
• v.23 no.2 s.54
• /
• pp.88-92
• /
• 1999

Hydrolysis properties of ginseng saponins in processing of extraction with vacuum impulse system extraction method were compared with multi-stage extraction methods. Crude saponin content of the extract produced by vacuum impulse system extraction method was $11.5\%,$ compared with multi-stage extraction method (about $8.13\%).$ Also the yield of the extract increased about $6.7\%.$ The flavor and aroma of ginseng extract with vacuum impulse system extraction method are stronger than multi-stage extraction methods and people have a tendency to like more. The color was similar to existing extraction items and the liquidity ratio was high. Vacuum impulse system extraction method could save human resources because of short extraction time and automatic operation of processing. With HPLC pattern, We could ascertain the truth that hydrolysis properties of ginseng saponin was restrained in the extraction processing, vacuum impulse system extraction method.

• Journal of the Korean Vacuum Society
• /
• v.16 no.5
• /
• pp.383-387
• /
• 2007

In this paper the design of the discharge cleaning system for KSTAR vacuum vessel is described. We first discuss about the parameters which are related the efficiency of discharge cleaning. The RG(RF-assisted Glow) discharge which has the ignition and sustain pressure lower than those in the case of DC discharge, thus has the higher efficiency of discharge cleaning. So we adopt the RG discharge, in practical design, for KSTAR discharge cleaning system. For uniformity of the cleaning effect, we plan to install two discharge cleaning systems in A- and I-port of the KSTAR vacuum vessel. The designed system will be adapted for the study of the fuel recycling and of the boronization as well as the discharge cleaning of the KSTAR vacuum vessel.