• Journal of Korea Society of Industrial Information Systems
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• v.10 no.4
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• pp.110-119
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• 2005

This study develops three dimensions of a supply chain structure (i.e., supply network, conversion network, distribution network) and proposes a balanced scorecard (BSC) model in order to measure management performance. We may conclude that management performance depends on the supply chain structure, and performance of distribution network is better than that of supply and conversion networks based on the result of Scheff multi-comparison.

• Journal of Microbiology and Biotechnology
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• v.1 no.1
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• pp.63-69
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• 1991

Performance of column type bioreactor packed with immobilized cyclodextrin glucanotransferase (CGTase) on chitosan and Amberite IRA 900 was evaluated for cyclodextrin(CD) production. For CGTase immobilized on chitosan, the maximum CD conversion yield of 42% was achieved at the range of 88-168 units of immobilizied CGTase per gram of chitosan, retention time of 0.3 hr, and from 5.0% (w/v) of partially cyclized soluble starch. On the other hand, for CGTase immobilized on Amberite IRA 900, the maximum conversion yield of 40% was obtained at the range of 3.6-11.0 units of immobilized CGTase per gram of carrier and retention time of 1.2 hr from 5.0% of substrate. Above CD conversion yields are almost identical level with that can be obtained with soluble CGTase of 47%. The productivities of bioreactor packed with immobilized CGTase were 17.0g of CD/lㆍhr for amberite IRA 900 and 15.5g of CD/lㆍhr for chitosan. The partially cyclized starch with soluble CGTase were more suitable as substrate to achieve better CD conversion yield, and 5% (w/v) of partially cyclized soluble starch containing 10% (w/w) of CD was found to be most suitable to obtain maximum CD conversion yield.

• International Journal of Fluid Machinery and Systems
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• v.5 no.1
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• pp.38-48
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• 2012

One centrifugal compressor is applied for refrigeration and its working substance is R134a. The operating points obtained by using similar conversion at different rotation speeds are compared with the numerical results. They keep consistent with each other while the rotation speeds are lower, but the error between them will become large with the increasing of the rotation speed. Then the operating points are obtained when the working substance is air by using two similar conversion methods separately. Based on the comparison, it can be obtained that the result of keeping the specific volume ratio of inlet and outlet is more accurate than the result of maintaining Ma number. Then the test result is compared with the similarity result and the numerical result when the working substance is air. It is obtained that the similarity result is more consistent with the test result better than the numerical result and the trend of efficiency and pressure ratio change with the flow rate is consistent with the test result. In the process of similar conversion, the efficiency ${\eta}$ is no useful for similitude design and it has less influence on the conversion result.

• Journal of the Korean Society for Precision Engineering
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• v.25 no.11
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• pp.83-89
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• 2008

The Effect of Space Velocity(SV) on NOx conversion rate was performed to develop NOx reduction after-treatment system. SV is calculated from engine exhaust gas volume and SCR catalyst volume. Found the Urea injection duty of maximum efficiency for NOx conversion if increase SV, NOx Conversion rate is down. Especially, when SV is more than $110,000h^{-1}$, NOx conversion rate decrease suddenly. Same case, if SV is lower than $40,000h^{-1}$, NOx conversion rate is down. Also, the characterization of Urea-SCR system was performed. Three candidate injectors for injecting Urea were tested in terms of 속 injection rate and NOx reduction rate. The performances of SCR catalytic converter on temperature were investigated. The performance of Urea-SCR system was estimated in the NEDC test cycle with and without EGR. It was found that nozzle type injector had high NOx conversion rate. SCR catalytic converter had the highest efficiency at the temperature of $350^{\circ}C$. EGR+Urea-SCR system achieved NOx reduction efficiency of 73% through the NEDC test cycle.

• Journal of electromagnetic engineering and science
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• v.8 no.3
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• pp.114-118
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• 2008

Direct-conversion RF front-end for 5-GHz WLAN is implemented in $0.18-{\mu}m$ CMOS technology. The front-end consists of a low noise amplifier, and low flicker noise down-conversion mixers. For the mixer, an inductor is included to resonate out parasitic tail capacitances in the transconductance stage at the operating frequency, thereby improves the flicker noise performance of the mixer, and the overall noise performance of the front-end. The receiver RF front-end has 6.5 dB noise figure, - 13 dBm input IP3, and voltage conversion gain of 20 dB with the power consumption of 30 mW.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.169-171
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• 2007

A breaking layer was introduced to conventional decal transfer method in membrane electrolyte assembly fabrication for high catalyst transfer ratio. In this study, the modified decal transfer method with high catalyst transfer ratio was introduced and its performance is studied. The structural features of electrodes made by decal method were investigated using scanning electron microscopy and current-voltage polarization measurement.

• Journal of Power System Engineering
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• v.14 no.1
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• pp.27-33
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• 2010

We investigate some operation characteristics and energy efficiency of the BLDC motor system driven by different two types power conversion method depends on same battery source for applying to electrical motor propulsion system of a small ship. Also, we suggest an estimation manner of operating performances such as total running distance and operating speed of ships from basic discharge voltage characteristics of batteries. Through some experiments, direct power conversion was better than indirect method on the view point of energy efficiency and the voltage discharge characteristics could be used as important design factor for estimating operating performances of small ships driven by electrical motors.

• Journal of Korean Society for Atmospheric Environment
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• v.15 no.E
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• pp.9-16
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• 1999

This study has been focused on NO conversion for metal-incorporated silicates(Fe-silicate, Mn-silicate, and Fe-Mn-bimetallosilicate) with a similar MFI type. Used metallosilicates were prepared by the rapid crystallization method. Their catalytic performance for the conversion of NO under excess O2(10%) condition with the addition of hydrocarbon of low concentration(1,100ppm n-C8H18) were investigated. As a result, the NO conversion on the Fe-Mn-bimetallosilicate was enhanced compared with on the Fe- or Mn-silicates. Furthermore, the performances for NO concentration on Fe-Mn-bimetallosilicate more increased with an increased in n-C8H18 concentration, a decrease in NO concentration, and an increase in O2 concentration.

• Journal of Aquaculture
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• v.18 no.2
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• pp.130-132
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• 2005

Genomics research has two ultimate applied goals: to Isolate and clone genes of economic importance for bio-technology and gene-assisted selection (GAS), and to locate and use markers for marker-assisted selection (MAS) in selective breeding programs. To this end, we have identified linked markers for feed conversion efficiency growth rate, and disease resistance to enteric septicemia of catfish (ESC). Three microsatellite markers Ip266, Ip384, and Ip607 were identified to be linked to feed conversion efficiency. Similarly one marker each was identified to be linked to growth rate (Ip607) and disease resistance to ESC (Ip477). Ip607 marker linked to both growth rate and feed conversion efficiency, indicating that the QTL for both growth rate and feed conversion efficiency may either be the same or located in the same chromosomal region in the catfish genome. On phenotypic evaluation, certain traits such as growth rate can be accurately evaluated by body weight evaluation while other traits such as disease resistance can be quite complex. The linked DNA markers will be highly useful for MAS programs and for directing further efforts of genomic mapping for important quantitative traits.

• Journal of the Korean Ceramic Society
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• v.51 no.6
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• pp.533-538
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• 2014

Today, silicon and epoxy resin are used as materials of conversion lenses for white LEDs on the basis of their good bonding and transparency in LED packages. But these materials give rise to long-term performance problems such as reaction with water, yellowing transition, and shrinkage by heat. These problems are major factors underlying performance deterioration of LEDs. In this study, in order to address these problems, we fabricated a conversion lenses using glass, which has good chemical durability and is stable to heat. The fabricated conversion lenses were applied to a remote phosphor type. In this experiment, the conversion lens for white LED was coated on a glass substrate by a screen printing method using paste. The thickness of the coated conversion lens was controlled during 2 or 3 iterations of coating. The conversion lens fabricated under high heat treatment temperature and with a thin coating showed higher luminance efficiency and CCT closer to white light than fabricated lenses under low heat treatment temperature or a thick coating. The conversion lens with $32{\mu}m$ coating thickness showed the best optical properties: the measured values of the CCT, CRI, and luminance efficiency were 4468 K, 68, and 142.22 lm/w in 20 wt% glass frit, 80 wt% phosphor with sintering at $800^{\circ}C$.