• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.595-596
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• 2008

가스 하이드레이트의 생성속도와 전환율을 높이며, 동시에 생성유도시간을 억제하기 위한 방법으로 다공질 물질을 활용하여 공극 내에 물을 함침시킨 후 가스와 반응시키는 제조방법을 개발하였다. 내용적 10 L 의 대용량 고압 반응기를 제작하여 실험을 수행하였으며, 장치 대형화에 따른 다공질 실리카겔의 다짐현상에 의한 발열제어 등에 대한 문제점은 특별히 나타나지는 않았다. 하이드레이트 형성을 위한 구동력이 높을수록 생성속도가 좋아지는 것을 확인하였다. 일반 벌크상 하이드레이트 제조법과 비교하여 매우 높은 생성속도 및 전환율, 거의 제거된 생성유도시간 등은 응용기술로 활용하기에 매우 바람직한 특성으로써 선택적인 가스분리, 가스저장 매체로 활용이 가능하다.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2012.11a
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• pp.71-74
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• 2012

본 논문에서는 현재의 HDTV와 3DTV보다 4배 이상 초고화질의 UHDTV와 Full-HD급 3DTV 등 지상파에서의 차세대방송 구현 가능성을 DVB-T2 전송방식과 HEVC 압축방식을 기반으로 설명한다. 4K 혹은 8K-UHDTV 대용량 데이터전송을 위하여 일본과 여러 나라에서 새로운 전송기술을 연구 중이지만 여기서는 현재 상용화된 기술 중 DVB-T2 전송기술을 중심으로 자료를 통하여 가능성을 알아본다. 지상파방송 디지털전환에 이어 또다시 차세대방송을 위한 전환의 성공조건으로 UHDTV와 3DTV전송도 중요하지만 시청자 직접수신과 실내수신 및 언제 어디서나 자유로운 수신환경 제공도 매우 중요하다. 그러므로 본 논문에서는 효율적인 주파수 활용과 수신능률 향상을 위하여 VHF대역과 UHF 700MJHz대역 등 2개의 서로 다른 주파수 대역을 이용한 SFN 송출망의 효과를 제시하고, 소출력 Gap Filler 및 가정용 SFN Gap Filler를 활용한 자유로운 수신환경 구성을 제안하고 있다.

• Proceedings of the Korea Association of Information Systems Conference
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• 2005.12a
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• pp.314-325
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• 2005

정보통신기술의 발달로 인하여 최근 가업의 제품수명주기는 점점 짧아지고, 성장산업과 사양산업의 전환도 급격해졌다. 급변하는 정쟁 환경 속에서 기업의 가치사슬을 전략적으로 통 합하고, 핵심역량을 극대화하기 위해서 c- Commerce, RTE, 협업 등의 가상기업 관련 개념이 부상하고 있다. Ubiquitous 환경에서 기업 경쟁력을 제고하기 위한 목표로서 협업 네트워크를 기반으로 하는 가상기업으로의 전환이 필수적이다. 본 연구는 기존에 논의되었던 가상기업의 정의 및 개념에 대해 문헌연구 및 사례조사를 통해 가상기업의 확장된 범주를 알아보고, 가상기업 연구에 대한 포괄적인 틀을 제공하고자 한다. 또한 가상조직, 협업 네트워크 등의 가상기업 관련 문헌연구를 통해 u- Business 환경의 가상기업 연구의 참조모델을 제시하고, 연구방법론을 적용하여 분석, 연구하여 가상기업의 연구를 이해하고 흐름을 분류하고자 한다. 본 연구결과는 Ubiquitous 환경에 민첩하게 대응하고자 하는 기업들에게 환경 변화에 따른 전략 및 비즈니스 모델의 수정에도 의미를 제공하고자 한다.

• Archives of design research
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• v.17 no.2
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• pp.363-372
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• 2004

In the new millenium of information and digital age, the vogue cycle has been gelling shorter and shorter and the individualistic and high quality preference of contemporary consumers drive the small quantity production by order. The traditional screen printing system can not hold the competitive edge anymore. In order to actively meet the demand of the fast evolving market, compete with other nations, and produce high value-added products, we need the new production system to meet the individual needs promptly. Mass production using the traditional screen printing system has the economic advantage of the production speed and cost. The digital textile printing system digitalizes the total process from the design to the printing and omits the separation and engraving. It is more suitable to produce the multiple item-small quantity and add more values to its products. It has also the advantage of less pollution problem.

• Proceedings of the Korean Society for Quality Management Conference
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• 2007.04a
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• pp.174-186
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• 2007

최근의 기업 환경은 글로벌화의 진전과 산업문명의 발달, 정보 습득이 용이 등으로 급속도로 소비자 중심의 시장으로 전환되었으며 이로 인해 기업 간의 경쟁은 급격히 가속되고 있는 상황이다. 이러한 상황 아래 고객에게 제공하는 가치가 유사한 기업들은 자사의 제품과 서비스를 차별화하여 기업의 경쟁력을 강화하기 위해 다양한 방법을 시도하고 있다. 이 다양한 방법들 중 대표적인 한 가지가 자사의 브랜드를 강력하게 만들어 관리하는 것이다. 현대의 소비자들은 단지 제품이나 서비스의 품질, 또는 가격들 중 하나로 제품을 선택하는 것이 아니라 종합적 경험으로 자신에게 각인되어 있는 브랜드의 선택을 통하여 제품이나 서비스를 구매하게 된다. 또 하나의 대표적인 방법이 경영혁신 활동이다. 기업은 기존의 업무 방법을 재현해서만은 지속적인 경쟁력을 유지할 수 없다. 변화하는 기업 환경에 맞춰 기업의 가장 중요한 부분을 본질적으로 변화 시켜야만 기업의 경쟁력을 지속적으로 유지, 향상 시킬 수 있다. 이에 본 연구에서는 기존에 연구된 문헌자료를 토대로 이론적 배경을 고찰하고 기업들의 경영혁신 추진 실태 조사와 K기관의 NBCI모델 통하여 산출된 브랜드 경쟁력 지수간의 상관관계를 분석함으로써 경영혁신 활동이 기업의 브랜드 자산 가치에 어떤 영향을 미치고 있는지 살펴보고자 한다.

• Journal of Life Science
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• v.25 no.10
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• pp.1164-1168
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• 2015

Previous research showed that chlorphenesin galactoside (CPN-Gal), a preservative in cosmetics, was safer than CPN against human skin cells [9]. To establish a stable and long-term process for CPN-Gal production, we investigated the repeated-batch process. In this process, β-gal-producing recombinant Escherichia coli cells were immobilized in calcium alginate beads, and CPN was converted to CPN-Gal by the transgalactosylation reaction. The process was conducted in a 300 ml flask, which contained E. coli cell-immobilized alginate beads, 33.8 mM of CPN, and 400 g/l of lactose. The pH and temperature were 7.0 and 40℃, respectively. During the repeated-batch operation, four consecutive batch operations were conducted successfully until 192 hr. The conversion yield of CPN to CPN-Gal was 64% during 192 hr, which was higher than the values in previous reports [3, 13]. Thereafter, however, the conversion yield gradually decreased until the operation was finished at 336 hr. Western blotting of immobilized E. coli cells revealed that β-gal gradually decreased after 192 hr. In addition, alginate beads were cracked when the operation was finished. It is probable that, including this loss of E. coli cells by cracks, deactivation, and product inhibition of E. coli β-gal might lead to a gradual decrease in the production of CPN-Gal after 192 hr. However, as the purification of β-gal is not necessary with β-gal-producing recombinant E. coli cells, β-gal-producing E. coli cells might be a practical and cost-effective approach for enzymatically synthesizing CPN-Gal. It is expected that this process will be extended to long-term production process of CPN-Gal for commercialization.

• Journal of Technology Innovation
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• v.28 no.2
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• pp.1-36
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• 2020

While the policy intervention of each country for the promotion of renewable energy is strengthened, Korea introduced Feed-in Tariff (FIT) in 2002 to directly support the development of renewable energy. But in 2012, the shift of policy instrument that from FIT to Renewable Portfolio Standard (RPS) is occurred. This is a unique background that is currently found only in Korea, and new answers that focus on the outcomes of the shift of policy instruments are needed in addition to the existing discussion of comparison of FIT and RPS. Therefore, this study analyzed the change of policy efficiency after the shift to RPS using Data Envelopment Analysis(DEA) and Malmquist Index. In the result of analysis, a difference in the improvement of policy efficiency after in shift to RPS is found among each renewable energy source. This result is because renewable energy companies voluntarily entered the market only for energy sources that have secured technology or price competitiveness, and this indicates that the performance of renewable energy after the RPS shift has been concentrated on specific energy sources. As a result of this study, considering that the goal of renewable energy policy is to expand distribution and to drive growth engines, multi-faceted analysis is required in consideration of technology and market in selecting policy instruments.

• Journal of Plant Biotechnology
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• v.29 no.4
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• pp.229-233
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• 2002

Ferritin is ubiquitous in bacteria, animals and plants. Ferritin is thought to play two main roles in living cells to provide iron for the synthesis of iron protein such as ferretoxin and cytochromes and to prevent damage from radicals produced by iron/dioxygen interaction. To enhance the resistance of potato to Erwinia carotovora, the soybean ferritin gene was introduced into the potato either under CaMV 35S or hsr203J promoter. Potato transgenic plants were screened by PCR analysis using specific primers to the ferritin gene. Expression of ferritin gene under CaMV 35S and hsr203J promoter in potato transgenic plants was confirmed by northern blot analysis. hsr203J promoter known to pathogen inducible in tobacco drives the induction upon Phytophthora infestan in potato and the transcript level of ferritin gene was extremely high after 24 hours post inoculation. One of transformants under CaMV 35S promoter was increased 2.5 fold than untransformant. Each one of transgenic potato containing gene promoter CaMV 35S and hsr203J-ferrtin fusion exhibited tolerance against potato soft rot.

• The Korean Journal of Pharmacology
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• v.26 no.2
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• pp.121-126
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• 1990

The contractility of isolated rat atria, suspended in Krebs-Ringer bicarbonate medium containing 5.5mM glucose, was depressed approximately 50% by 0.1 mM of lidocaine. Partial recovery of the lidocaine-depressed contractility was achieved by the metabolizable substrates pyruvate, acetate, and fructose, but not by addition of glucose. Glucose produced the dose-dependent increase in the force of contraction of normal atria, whereas pyruvate, acetate, and fructose produced no significant effect in the contractile activity of the normal atria. In the absence of exogenous glucose lidocaine produced more marked depression of atrial contractility than that in the presence of exogenous glucose. The results of this study may confirm that the utilization of cardiac glycogen is also inhibited by lidocaine at sites of the glucose phosphate isomerase step or step between glycogen to glucose-6-phosphate.

• The Korean Journal of Pesticide Science
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• v.7 no.1
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• pp.45-50
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• 2003

This study was conducted to understand the role of oxidative enzyme cytochrome $P_{450}$ in the bioactivation of benfuracarb and to know metabolites of benfuracarb by cytochrome $P_{450}$. The bimolecular imhibition rate constant $(k_i)$ of benfuracarb on acetylcholinesterase (AChE) was as low as $1.1{\times}10^3\;M^{-1}\;min^{-1}$, suggesting that benfuracarb should be activated for its toxic action. The potency of benfuracarb on AChE in the oxidase system (cytochrome $P_{450}$ + NADPH) in vitro was 10-fold higher than that of control (cytochrome $P_{450}$). Such a similar result was also found in the oxidase + PBO system. In vivo the $I_{50}$ of benfuracarb was 22.7mg $kg^{-1}$, but pie-treatment of piperonyl butoxide (PBO) reduced the $I_{50}$ by >100mg $kg^{-1}$. This result suggests that cytochrome $P_{450}$ was involved in the activation of benfuracarb. Using microsomal oxidase system, metabolites of benfuracarb were elucidated. Fifty-eight percent of benfuracarb was converted to carbofuran, a major toxic metabolite, in the oxidase system, while only less than two percent of benfuracarb was converted to carbofuran in the oxidase + PBO system. These results also suggest that cytochrome $P_{450}$ was involved in the activation of benfuracarb. Overall results indicate that cytochrome $P_{450}$ could be involved in the bioactivation of benfuracarb to carbofuran.