• The Journal of the Acoustical Society of Korea
• /
• v.28 no.8
• /
• pp.796-805
• /
• 2009

In this paper, a fabrication process for PZT preform of 1-3 type piezo-composite were studied using powder injection molding (PIM). The viscosity and the Pressure-Volume-Temperature (PVT) characteristics of the fabricated PZT feedstock were analyzed. The filling patterns, pressure, temperature distributions, and forming defects of the preform were analyzed with 3D TIMON commercial packages during PIM process. Also the fabrication conditions and the delivery system of the preform were optimized during the entire PIM process. Based on the simulated results, the preform having uniform distributions of the PZT rod was fabricated with the PIM process.

• Proceedings of the Korean Powder Metallurgy Institute Conference
• /
• 2002.04b
• /
• pp.23-25
• /
• 2002

• Applied Chemistry for Engineering
• /
• v.20 no.4
• /
• pp.363-369
• /
• 2009

High oil price and biodiesel expansion lead the surplus of glycerol in the market. Glycerol has been used as a raw material itself at petroleum chemistry, paint, tobacco, household products and cosmetics in the conventional market. Recently, many research to find new applications of glycerol as a low-cost feedstock for functional derivatives have led to the introduction of a number of selective processes for converting glycerol into commercially value-added products. The recent studies on the development of new value-added glycerol derivatives will be reviewed.

• 한국신재생에너지학회:학술대회논문집
• /
• 2005.06a
• /
• pp.561-564
• /
• 2005

Gasification has been regarded as a very important technology to decrease environmental pollution and to obtain higher efficiency. The gasification process converts carbon containing feedstock into a synthesis gas, composed primarily of CO and $H_2$. And the synthesis gas can be used as a source for power generation or chemical material production. Through more than nine years, IAE developed and upgraded several gasification/melting pilot plant system, and obtained a good quality synthesis gas. This paper illustrates the gasification characteristics and operation results of two 3 ton/day synthesis gas production facilities. One is entrained-bed slagging type coal gasifier system which is normally operated in the temperature range of $1,400\~1,450^{\circ}C,\;8\~10$ bar pressure. And the other is fixed-bed type gasification/melting furnace system using MSW and industrial wastes as a feedstock.

• Journal of Microbiology
• /
• v.42 no.1
• /
• pp.51-55
• /
• 2004

The influence of feedstock amino acids, salt, carbon and nitrogen sources on glutathione production by Saccharomyces cerevisiae FF -8 was investigated. Glucose, yeast extract, KH$_2$PO$_4$, and L-cysteine were found to be suitable feedstock. Highest glutathione production was obtained after cultivation with shaking for 72 h in a medium containing glucose 3.0% (w/v), yeast extract 3.0%, KH$_2$PO$_4$ 0.06% and L-cysteine 0.06%. The glutathione concentration achieved using this medium increased 2.27-fold to 204 mg/l compared to YM basal medium.

• 한국신재생에너지학회:학술대회논문집
• /
• 2009.06a
• /
• pp.126-129
• /
• 2009

In this study, it was aimed to develop the re-use technology of ultra-fine silicon powders, by-products during the current production process of high purity poly-Si feedstock. For this goal, the compacts of the silicon powders were tried to fabricate by CIP (Cold Isostatic Pressing) method using silicon rubber mold without chemical binder materials. The density ratio of the silicon powder compacts reached 74%. In order to simulate the actual handling and charging conditions of feedstock material in casting process, a shaking test was carried out and mass loss measured. Finally, the silicon powder compacts were melted using a cold crucible induction melting method and the purity assessment was conducted by Hall effect measurement.

• Proceedings of the Polymer Society of Korea Conference
• /
• 2006.10a
• /
• pp.152-152
• /
• 2006

Polyolefins show a very healthy growth rate among commodity polymer resins due to their low feedstock prices, recyclable and environmentally friendly characteristics and easily controllable performances. Capacity investment in polyolefin field is now moving from technology region to consumer region and feedstock region. Therefore, key success factors for polyolefin business in the other region such as Korea are cost reduction, development of highly value-added products and new applications and substitution of PVC, PS, PET and other EPs. To add additional value to commodity polyolefin products, high level of platform technology such as catalyst, process and structure-properties relationship is needed. Progress on polyolefin products has been very closely related to catalyst and process technology. According to this trend, SK Corporation has devoted a lot of research effort into development of new value-added polyolefin products based on the proprietary technology platform.

• Journal of the Korean Operations Research and Management Science Society
• /
• v.15 no.1
• /
• pp.37-46
• /
• 1990

Biomass to methane production is a good supply of substitutable energy resources. The economic viability of these systems depends a great deal on cost effective production methods and facilities. The operational problem is to determine the time eto allocate to each batch of several feedstocks for each digester and to determine the number of batches for each digester so as to maximize biogas production for two identical digesters over a fixed planning horizon. This paper provides an efficient approximation procedure which is based on decomposition of the problem and the analysis of incremental gas production function for each feedstock. The computational experience for the heuristic procedure was also reported.

• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 2004.10a
• /
• pp.148-151
• /
• 2004

Different kinds of feedstock of semisolid a356 aluminum alloy manufactured by EMS stirring only, inoculation of Al-5Ti-B only and combination of inoculation and EMS stirring were investigated. It is found that the grain size of these feedstock are $350{\mu}m$ for EMS casting only, $320{\mu}m$ for inoculation by Al-5Ti-B, and $100{\mu}m$ for the combination of EMS stirring and inoculation of Al-5Ti-B master alloys. The microstructure of the sample obtain by combination of inoculation and EMS system show the best homogeneousness and finest grains.

• Transactions of the Korean Society of Machine Tool Engineers
• /
• v.14 no.5
• /
• pp.80-86
• /
• 2005

High velocity oxy-fuel thermally sprayed coating of the WC-Co cermet material is a well-established process for modifying the surface properties of the structural components exposed to the corrosive and wear attacks. The hard WC phase in the coating resists to the wear while the soft metallic Co increases the adhesive and cohesive bonding properties. The coating properties deposited by the HVOF process are greatly dependent on the feedstock materials and processing parameters. The effects of the feedstock material and process coating parameters including the in-flight particle parameters and resultant coating microstructures were observed in this paper.