• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.10a
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• pp.412-414
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• 2013

본 논문에서는 UWB 기술 기반 WiMedia WSS 환경에서 기존의 QoS를 고려한 D-SoQ 방식을 개선하여, WLP 디바이스와 WUSB/DRD 전송 모드의 우선순위에 따른 차등화 된 서비스 전송률을 부여하는 방식을 제안한다. 제안하는 방법은 트래픽 스트림의 우선순위에 따라 수율 및 SoQ 성능의 차등화를 가능하게 한다.

• Journal of the Korea Safety Management & Science
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• v.14 no.1
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• pp.179-187
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• 2012

This paper presents a six sigma application case study for an automobile PCSV manufacturing process using rolled throughput yield improvement activity. Hidden factor and first yield concept is introduced and DMAIC procedure is implemented to maximize the first pass yield. The result of the six sigma project amounts to the reduction of failure cost of 0.1 billion won per year in the PCSV manufacturing process. This paper can benefit six sigma practitioners in some ways.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.10B
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• pp.862-875
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• 2003

본 논문에서는 IEEE 802.11 규격을 기반으로 다중 홉 Ad Hoc 모드에서 비실시간 및 실시간 트래픽에 대한 통합 서비스를 지원하는 Wireless LAN을 구성할 때, 분산 방식으로 실시간 서비스의 우선권을 고려한 채널 액세스의 차별화를 제공할 수 있는 매체접근제어(Medium Access Control: MAC) 프로토콜의 구현 방안을 제안한다. 이를 위해 실시간과 비실시간 트래픽의 Contention Window (CW)를 서로 분리하며, 실시간 서비스의 지연 바운드에 따라 정해진 잔여 수명(residual time)을 우선권 설정에 반영함으로써 실시간 트래픽의 지연 요구 사항을 보장할 수 있도록 한다. 또한 실시간 트래픽의 부하에 따라서 적응적으로 offset 값을 조정함으로써 offset에 의해 발생될 수 있는 수율의 저하를 최소화한다. 제안된 방식은 기존 IEEE 802.11 MAC 규격의DCF (Distributed Coordination Function) 방식을 그대로 사용하면서 CSMA/CA 기반의 경쟁 방식을 통해서도 비실시간 트래픽과의 차별화가 가능하고, 또한 잔여 수명 시간을 고려한 동적인 우선권 할당이 가능하도록 하였다. 시뮬레이션에 의한 분석 결과에 따르면 기존 DCF와 비교할 때 실시간 단말의 용량을 2배까지 향상시킬 수 있으며, 트래픽 부하에 따라 적응적 제어를 통해 추가적인 성능 개선 효과를 확인하였다.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.83.2-83.2
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• 2013

정교한 생산 공정에 있어서 공정의 갑작스런 변동(Shift)나 점진적인 변화(Drift)에 대해서 얼마나 적절하게 대응하느냐는 생산 제품의 품질과 수율에 상당한 영향을 미친다. 이에 본 과제에서는 반도체 생산 공정에 따른 측정 결과를 분석하여 최상의 공정조건(Recipe)를 유지하기 위한 알고리즘을 개발하고, 개발된 알고리즘의 유효성 판단을 위한 시뮬레이션 툴을 개발하였다. 또한, 다양한 현장 조건을 충족할 수 있도록 사용자 임의의 데이타 구조를 정의하고, 기준 정보를 등록할 수 있도록 유연성이 부여된 사용자 UI를 개발하였다. 생산 설비로부터 공정 관련 데이타를 수집하고, 측정 설비로부터 계측데이타를 수집한 후, 사용자가 설계한 APC 로직에 의해 실시간 공정 제어가 가능한 시스템을 개발하여, 현장 엔지니어가 다양한 APC 로직을 설계하고 구현할 수 있도록 하였다. 현장 엔지니어용 툴은 Graphical Workflow 형태로 개발되었으며, 엔지니어가 복잡한 프로그래밍을 하지 않아도 직관적으로 설계/구현할 수 있도록 하였다. 분석을 위한 리포트 화면을 이용하여, 공정/측정 데이타에 대한 조회기능을 제공하고, Trend, Pair, X-bar 등의 다양한 분석용 챠트를 이용하여 파라미터 분석 기능을 제공하였다. 본 과제에서 증착 장비용 제어 알고리즘을 적용하여 테스트하였으며, 30% 이상의 Cpk 개선 효과를 얻을 수 있었다.

• Korean Journal of Food Science and Technology
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• v.23 no.4
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• pp.485-489
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• 1991

In order to study the effects of blanching and germination of soybean on the quality of soymilk, the soybeans were differently treated as follow; (1) blanched for 5 min at $100^{\circ}C$, (2) germinated for 2 days at $25^{\circ}C$, (3) germinated for 2 days and then blanched for 5 min at $100^{\circ}C$. The qualities of various soymilks prepared from the treated soybeans were compared with those of soymilk from the untreated soybeans. Blanching of soybeans decreased yields, solid materials, viscosity, total protein, soluble nitrogen, and total sugar of soymilk but no effect on its free sugar contents, specific gravity, and pH. The blanching, however, improved the sensory properties and decreased the n-hexanal contents of soymilk to about 1/2.4. Germination of soybeans improved the yields, physical, chemical, and sensory properties and decreased the n-hexanal contents of soymilk to about 1/5. The germination plus blanching of soybeans showed kind of combined effects of germination's and of blanching's, resulting in the decrease of n-hexanal to about 1/10 and improvement in sensory properties of soymilk.

• Food Science and Preservation
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• v.23 no.3
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• pp.319-325
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• 2016

This study was designed to develop a manufacturing process for ginseng concentrate with reduced unpleasant aroma and bitter taste. Two types of ginseng, white and red, were extracted under six different conditions (the 1st to the 6th step) of temperature ($65{\sim}95^{\circ}C$) and ethanol concentration (0~70%). Six extracts of each ginseng were evaluated by a sensory test, and assayed for crude saponin, ginsenosides, and acidic polysaccharides. The content of crude saponin in the extracts decreased with extraction time. There was no significant difference in the crude saponin content between white and red ginseng extracts. The yield of red ginseng extract was higher (45%) than that of white ginseng. No significant difference was observed in the acidic polysaccharide content between red and white ginseng extracts. $Rg_3$, a specific ginsenoside in red ginseng, was detected in the 1st to 6th extracts of red ginseng. Bitterness, astringency, and sourness of ginseng extracts decreased as the extraction steps proceeded. The composite of the 1st, 2nd, and 6th step extracts decreased bitterness and astringency, and the highest overall acceptance. Compared with commercial beverages, the composition of the three extracts is the desirable method to decrease the bitter and astringent tastes, and the overall unpleasant flavor of ginseng.

• Korean Journal of Microbiology
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• v.37 no.1
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• pp.92-99
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• 2001

High-cell-density cultivation of Ralstonia eutopha KHB 8862 by fed-batch fermentation in a 200 l pilot plant was carried out for the mass production of poly(3-hydroxybutyrate) (PHB). After 80 h of cultivation, the dry cell weight (DCW), PHB concentration, and PHB yield from fructose syrup reached 168 g/l, 74%DCW, and 0.27 (w/w), respectively, resulting in a productivity of 1.6 g of PHB/L/h. Based on these results, the PHB production cost from bacterial fermentation was analyzed and economic evaluation was performed. In the case of new investment being implemented or not, the production cost of PHB was US$ 3.15/kg and US$ 2.41/kg, respectively. PHB productivity and PHB yield on a carbon substrate were both important factors to be optimized. The increase of PHB yield on a carbon sources significantly decreased the PHB production cost but the increase in productivity had a relatively slight effect on the decrease in PHB production cost because the cost of carbon sources (37%) for PHB was larger in proportion to total cost than the depreciation cost (17%). These results suggest that the increased PHB yield from carbon sources and the development of new cheaper substrates would be more effective in decreasing PHB production cost than the increase in productivity. It was demonstrated that PHB is not in competition with consumable plastics such as PET in present market. Therefore, it is essential to lower production cost to be used as a bulk product and desirable to develop new application fields for PHB such as biomedical and cosmeceuticals.

• Nuclear Medicine and Molecular Imaging
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• v.41 no.6
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• pp.561-565
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• 2007

Purpose: Lipophilic cations including tetraphenylphosphonium (TPP) salts penetrate the hydrophobic barriers of the plasma and mitochondrial membranes, resulting in accumulation in mitochondria in response to the negative inner transmembrane potentials. The development of radiolabeled phosphonium cations as a noninvasive imaging agent may serve as a new molecular "voltage sensor" probe to investigate the role of mitochondria in the pathophysiology and diagnosis of cancer. Materials and Methods: We have synthesized a reference compound (4-fluorophenyl)triphenylphosphonium (TPP) and a labeled compound $[^{18}F]$TPP via two step nucleophilic substitution of no-carrier-added $[^{18}F]$fluoride with the precursor, 4-iodophenyltrimethylammonium iodide, in the presence of Kryptofix-2.2.2 and $K_2CO_3$. Result: The reference compound (4-fluorophenyl)triphenylphosphonium (TPP) was synthesized in 60% yield. The radiolabeled compound $[^{18}F]$TPP was synthesized in $10\sim15%$ yield. The radiochemical purity of the $[^{18}F]$TPP was $95.57{\pm}0.51%$ (n=11). Conclusion: $[^{18}F]$TPP was successfully synthesized that might have a potential to be utilized as a novel myocardial or cancer imaging agent for PET. However, it is required to improve the radiochemical yield to apply $[^{18}F]$TPP in preclinical or clinical researches.

• Journal of the Korean Vacuum Society
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• v.15 no.4
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• pp.395-403
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• 2006

It is known that $MgAl_2O_4$ has higher resistance to moisture than MgO, in humid ambient MgO is chemically unstable. It reacts very easily with moisture in the air. In this study, the characteristic of $MgAl_2O_4$ and $MgAl_2O_4/MgO$ layers as dielectric protection layers for AC- PDP (Plasma Display Panel) have been investigated and analysed in comparison for conventional MgO layers. MgO and $MgAl_2O_4$ films both with a thickness of $1000\AA$ and $MgAl_2O_4/MgO$ film with a thickness of $200/800\AA$ were grown on the Cu substrates using the electron beam evaporation. $1000\AA$ thick aluminium layers were deposited on the protective layers in order to avoid the charging effect of $Ga^+$ ion beam while the focused ion beam(FIB) is being used. We obtained sputtering yieds for the MgO, $MgAl_2O_4$ and $MgAl_2O_4/MgO$ films using the FIB system. $MgAl_2O_4/MgO$ protective layers have been found th show $24{\sim}30%$ lower sputtering yield values from 0.244 up to 0.357 than MgO layers with the values from 0.364 up to 0.449 for irradiated $Ga^+$ ion beam with energies ranged from 10 kV to 14 kV. And $MgAl_2O_4$ layers have been found to show lowest sputtering yield values from 0.88 up to 0.109. Secondary electron emission coefficient(g) using the ${\gamma}$- FIB. $MgAl_2O_4/MgO$ and MgO have been found to have similar g values from 0.09 up to 0.12 for indicated $Ne^+$ ion with energies ranged from 50 V to 200 V. Observed images for the surfaces of MgO and $MgAl_2O_4/MgO$ protective layers, after discharge degradation process for 72 hours by SEM and AFM. It is found that $MgAl_2O_4/MgO$ protective layer has superior hardness and degradation resistance properties to MgO protective layer.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.9
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• pp.432-439
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• 2020

To improve the relatively low economic efficiency of the Korean native pig, the Korean National Institute of Animal Science developed a novel pig breed, the Woori black pig (W), by crossing Korean native and Duroc (D) pigs. This study was conducted to evaluate the effects of W as a terminal sire on growth performance, body shape, and retail cut yield of crossbred pigs. By using a completely randomized design, 32 crossbred pigs were allotted to one of two treatment groups based on terminal sire. The two groups were LYD [(Landrace × Yorkshire) × D sire] and LYW [(Landrace × Yorkshire) × W sire]. The experimental assessments were conducted over 53 days. The terminal sire breed had no significant effect on body weight (BW) at d 53, or on BW gain, average daily gain, or days to reach a 90 kg body weight. Moreover, there were no significant differences in body length, body height, or chest depth between the two groups. However, there was a significant difference (p < 0.05) in backfat thickness between the LYD (17.29 mm) and LYW (18.96 mm) groups. Loin yield of crossbred pigs in the LYW group (13.11%) was significantly lower (p < 0.05) than that in the LYD group (13.85%). By contrast, the Boston butt yield was significantly higher (p < 0.05) in the LYW group (8.99%) than in the LYD group (8.21%). In conclusion, these results suggest crossbred pigs sired by a Woori black pig had growth performance, shape, and retail cut yield (except loin yield) Ed. Note: I assume the lower loin yield is a negative factor so I included this wording. similar to those sired by a Duroc pig. The results showed no overall negative effect Ed. Note: I assume the lower loin yield is a negative factor so I used this wording. on crossbred offspring, indicating the suitability of the Woori black pig as a terminal sire.