• 전기의세계
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• v.34 no.5
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• pp.292-298
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• 1985

전력 MOSFET은 산업 전반에 걸쳐 수요가 급증하고 있고, 멀지않아 장래에 컴퓨터, 통신, 메카트로닉스, 자동차등의 발달로 인하여 갑작스레 수요가 폭발하리라 예상하고 있다. 전력 MOSFET은 10년도 채 못되는 짧은 역사를 지니고 있기 때문에 국내에는 거의 소개된 바가 없으며, 이를 사용한 시스템을 생산하는 업체도 알려진 바 없다. 그러나, 에너지 자원이 빈곤한 우리나라에서는 전력 MOSFET을 사용한 절전형 전원이나 조절기의 개발이 시급하리라 생각된다. 또한 전력MOSFET은 LSI급의 IC제조시설을 활용하여 제작이 가능하기 때문에, 비교적 소규모 시설 투자에 의해 생산시설을 갖출 수가 있다. 따라서, 국내에서도 반도체 기술의 다양화 측면에서라도 전력MOSFET의 개발을 신중히 검토해야 할 때가 왔다고 생각한다.

• 전기의세계
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• v.46 no.2
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• pp.13-22
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• 1997

최근 메모리 산업의 침체로 인하여 비메모리 분야의 관심이 높아지고 있다. 비메모리 분야 하면 주로 ASIC(Application Specific IC)이 떠오르지만, 대부분이 소량 다품종의 디지탈 시스템이기 때문에 사업이 쉽지 않다. 새로이 개발되어 각광을 받고 있는 전력 MOS, IGBT, MCT 등은 작은 패턴의 셀이 칩 내부에서 병렬 연결되어 있기 때문에 메모리 제조공정과 유사하다. 전력반도체 기술을 선도하고 있는 일본, 미국, 유럽의 기업체도 국내의 메모리 생산기술이 세계적인 수준이라고 찬사를 보내고 있다. 따라서 메모리 기억용량이 증가하면 새로운 생산공정이 구축되고, 이때 밀려나게 된 장비를 전력소자 제작에 사용할 수 있다면, 감가 상각된 장비의 재활용을 통한 원가절감 등 여러가지 면에서 도움이 될 수 있으리라 사료된다.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.3
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• pp.283-288
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• 2007

In order to elucidate the relationship between the sludge retention time(SRT) and the toxicity of heavy metals, such as copper (Cu), cadmium(Cd), and zinc(Zn), in sequencing batch reactor(SBR) process, IC50 was estimated with measuring of INT-dehydrogenase activity in variable SRTs. When the concentrations of heavy metals were increased, the activity of INT-dehydrogenase was gradually decreased indicating the heavy metals inhibit bacterial activity. Cu showed higher toxicity than Zn and Cd. $IC_{50}$ of Cu, Cd, and Zn ranged from $0.37\sim1.96$ mg/L, $15.4\sim16.9$ mg/L, and $9.70\sim23.4$ mg/L, respectively. The toxicity of Cu and Zn was reversely proportional to the length of SRT. It is probably caused by the increased concentration of extracellular polymeric substances in longer SRT which absorb heavy metals. Therefore, the operation of SBR with increased SRT is desirable in treatment of industrial wastewater containing heavy metals.

• Food Industry
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• s.169
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• pp.104-115
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• 2002

Physiological effect of Korean black soybean pigment were investigated. Major anthocyanin pigments of Korean black soybean were extracted with $1\%$ HCI for 24hours at $4^{\circ}C$. Inhibitory effects of angiotensin converting enzyme

• Journal of the Korean Society of Physical Medicine
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• v.14 no.3
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• pp.91-107
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• 2019

PURPOSE: This study examined the effects of breathing exercise in the water on the pulmonary function and maximum phonation time in children with cerebral palsy. METHODS: The subjects were 24 children with cerebral palsy at GMFCS levels I-III, who were allocated randomly to either the aquatic breathing exercise group or general breathing exercise group 12 subjects per group. Each subject was required to complete 40 minutes of exercise twice a week for eight weeks. Those in the aquatic breathing exercise group performed aquatic breathing exercise, whereas those in the general breathing exercise group performed general aquatic exercise. RESULTS: Significant differences in $FEV_1$, PEF, VC, TV, ERV, and maximum phonation time were observed in the aquatic breathing exercise group after intervention, but there were no significant differences in either FVC, $FEV_1/FVC$, IC, or IRV. In the general breathing exercise group, there were no significant differences in the FVC, $FEV_1$, $FEV_1/FVC$, PEF, VC, IC, TV, IRV, ERV, and maximum phonation time after intervention. In terms of the pulmonary function, the two groups showed a significant difference in the change in $FEV_1$, PEF, and TV after intervention, but not in the FVC, $FEV_1/FVC$, VC, IC, ERV, IRV, and maximum phonation time. CONCLUSION: These results above show that aquatic breathing exercise training in water is more effective in improving the pulmonary function than general breathing exercise training.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.3D
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• pp.307-315
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• 2008

The aim of this study is to develop travel time estimation model by using Self-Organized Neural network(in brief, SON) algorithm. Travel time data based on vehicles equipped with GPS and number-plate matching collected from National road number 3 (between Jangji-IC and Gonjiam-IC), which is pilot section of National Highway Traffic Management System were employed. We found that the accuracies of travel time are related to location of detector, the length of road section and land-use properties. In this paper, we try to develop travel time estimation using SON to remedy defects of existing neural network method, which could not additional learning and efficient structure modification. Furthermore, we knew that the estimation accuracy of travel time is superior to optimum located detectors than based on existing located detectors. We can expect the results of this study will make use of location allocation of detectors in highway.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.45 no.2
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• pp.161-173
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• 2019

In this study, the antioxidative and inhibitory activity of tyrosinase and collagenase for the solvent extract and silica column fractions of Artocarpus nitidus were evaluated. The activities were quantified using the 4 parameter logistic. LC/MS analysis showed that the major component of the fractions was polyphenol and the total polyphenol content of the extract was $48.1{\pm}2.6mg\;GAE/g$. The radical scavenging activities ($SC_{50}$) for 1,1-diphenyl-2-picrylhydrazyl of the extract, fraction-1 and fraction-2 were 16.7, 42.0 and $10.1{\mu}g/mL$, respectively. The value for fraction-2 was the closest to ascorbic acid ($1.5{\mu}g/mL$). The tyrosinase inhibitory activity of the extracts and the fractions showed $IC_{50}$ of 64.9, 0.9 and $1.2{\mu}g/mL$, respectively, and overall activity was higher than that of kojic acid ($7.4{\mu}g/mL$) and arbutin ($119.0{\mu}g/mL$). In the experiment by zebrafish embryo, the whitening activity of fraction-2 (27.5%) was higher than that of kojic acid (18.6%), and there was no adverse effect up to $500{\mu}g/mL$ of fraction-2. For the collagenase inhibitory activity, the samples showed $IC_{50}$ of 139.8, 20.6, and $16.8{\mu}g/mL$, respectively, which were competitive to 1, 10-Phenanthroline ($55.4{\mu}g/mL$). The extract and fraction-2 showed $IC_{50}$ of 61.8 and $67.1{\mu}g/mL$ for elastase. These results suggest that A. nitidus extract can be used as a cosmetic material useful for antioxidant, whitening, and prevention of skin aging without adverse effects.

• 한국IT서비스학회:학술대회논문집
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• 2005.11a
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• pp.600-607
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• 2005

최근 무형자산의 중요성과 함께 많은 선진기업들은 지속적인 가치창출을 위한 전략수립 및 수행절차를 통해 경쟁우위를 갖는데 노력하고 있다. BSC는 기업의 전략을 전사조직 차원에서 실행 시킬 수 있는 기반을 조성하며, 기업의 자원을 핵심역량에 집중시켜 전략의 실행력을 구체화하기 위한 경영기법 중 하나로 자리잡고 있으며, 이미 국내 다양한 공공 및 민간부문에서 BSC도입을 통해 기업전략과의 연계를 강화해 나가고 있는 추세이다. 그러나 특정산업에 따라 각 산업의 특성을 고려한 BSC기반의 CSF(사업핵심성공요소)와 KPI(주요성과지표) Pool에 대한 실질적인 연구는 다소 미흡한 실정이다. 국내 건설업인 경우, 관리의 복잡성으로 인해 아직까지 재무적 손익 중심의 성과측정에 주로 의존하고 있으며, 비재무적인 측면의 다양한 성과지표를 포함하지 못하고 있는 실정이다. 이에 본 연구에서는 건설산업에 적합한 BSC관점을 고려한 건설업의 CSF/KPI Pool를 제시하고 도출된 CSF가 기업의 경영성과와 어떤 상관관계를 살펴봄으로써 실제 의미가 있는지 알아보는데 목적을 두고 있다. 본 연구결과는 건설 산업에서의 성과측정의 기초자료로서 활용되어 체계적인 성과관리의 향상에 기여하고 미래 성과창출의 유인을 제공하고자 한다.

• Food Industry
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• s.172
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• pp.38-56
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• 2003

The volatile compounds of traditional Kyungsando squid sikhe were identified by GC-MS. the amount of-zingibirene among identified volatile compounds was 19.73 mg/kg. The major volatile compounds of sikhe was (Z)-Di-2-propenyl disulfide,-curcumene, methyl

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.05a
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• pp.487-490
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• 2011

As international standards of ICT were recently recognized as a essential strategy to penetrate into global markets in advance, the competition for international standardization among advanced countries and companies has been intensified. Also, the convergence of ICT and other industry as well as that of ICT and broadcasting has caused the expansion of range and importance in standardization. It is necessary to set up the strategy of standardization on essential technology and implement it systematically in order to take leading position in global market of IC in smart information society of the 21th century. Therefore, in this paper, I'll suggest constructive strategies of standardization through analyzing the trend and environment of IC standardization.