• Environmental and Resource Economics Review
• /
• v.15 no.2
• /
• pp.269-296
• /
• 2006

With the concern of the potential problems which can be observed in terms of the power supply of renewable energies, we need to analyze the impact of additional power generation capacities of renewable energy sources on peak load. Each renewable energy sources are dependent upon wind speed, solar radiation, head differences caused by lunar calendar. Considering that these exogenous renewable energy sources follow their own stochastic distributions, we analyze the probability distribution of the impact of each renewable energy power supply on peak load. As a conclusion, we note that traditional tools used for the analysis of power supply such as capacity factors are no longer appropriate for the analysis of renewable energy sources in that perspective.

• KSBB Journal
• /
• v.7 no.3
• /
• pp.179-185
• /
• 1992

An anion-charged membrane was used for selective retention of coenzyme NAD(H) in reactor without any chemical modification. The membrane could reject permeation of NAD (H) (80.9%) but not reject permeation of product. The retention ratio was enhanced in the presence of albumin and Tris-maleate buffer. A bioreactor equipped with a membrane, NTR 7410 was constructed and used in the repeated batch production of sorbitol. NADH-dependent sorbitol dehydrogenase from sheep liver was used for the production of sorbitol from fructose. The coenzyme oxidized was regenerated with alcohol dehydrogenase. 47g/L sorbitol was produced for 198 hr with a substrate conversion ratio of 70%. The retention ratio was almost maintained throughout the entire reaction.

• Microbiology and Biotechnology Letters
• /
• v.13 no.2
• /
• pp.145-149
• /
• 1985

Studies were conducted on the conditions for yeast protoplast regeneration in Hansenula anomala var.anomala FRI YO-32 and Saccharomyces cerevisiae. Protoplasts lysed when suspended in hypotonic solutions of KCI, and the least degree of osmolysis was shown in the hypertonic solution containing 1.4M KCI for the strain FRI YO-32 or 0.8M KCI for S. cerevisiae. It was considered that the concentration of agrar and KCI, and protoplast plating method were the main factors influencing regeneration of yeast protoplasts. Yeast protoplasts were regenerated very favorably when embedded in the complete protoplast regeneration media containing 3％ agar as well as 0.4M KCI for the strain FRI YO-32 or 1.0M KCI for S. cerevisiae. It was shown from the relationship between protoplast formation and regeneration that the higher extent of protoplast formation, the lower extent of protoplast regeneration.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.25 no.3
• /
• pp.113-126
• /
• 2021

In order to develop active cooling systems for a hypersonic cruise vehicle, a series of studies need to be preceded on regenerative cooling technologies by using endothermic reaction of liquid hydrocarbon aviation fuels. Among them, it is essential to scrutinize fluid flow/heat transfer/endothermic pyrolysis characteristics of supercritical hydrocarbons in a micro-channel, as well as to acquire thermophysical properties of hydrocarbon fuels in a wide range of temperature and pressure conditions. This study, therefore, reviewed those technologies and analyzed major findings in related research areas which have been carried out worldwide for the development of efficient operational regenerative cooling systems of a hypersonic flight vehicle.

• Proceedings of the Korean Information Science Society Conference
• /
• 1999.10b
• /
• pp.274-276
• /
• 1999

지금까지 음악 정보를 표현하기 위하여 SMDL, NIFF, MIDI를 비롯한 많은 방법들이 제시되었다. 그러나 기존의 방법들은 독자적인 표현 방식을 사용하므로 서로 호환되지 않으며, 구현 방법과 과정이 매우 복잡한 문제점을 갖고 있다. 그리고 해당 어플리케이션의 가격이 매우 고가이므로 일반인들이 쉽게 접할 수 없었다. 따라서 본 논문에서는 이와 같은 문제점들을 해결하기 위하여 음악정보, 특히 리듬정보를 웹 표준 언어인 XML을 이용하여 표현하고 이를 웹에서 편집 및 재생하기 위한 새로운 방법을 제시하고 시스템을 구현한다. 그 결과 XML에 근거한 우리의 시스템은 일반인들이 쉽게 접할 수 있는 웹에서의 음악정보의 편집 및 출력, 그리고 사운드로의 재생 기능을 제공하는 동시에 완벽한 음악 정보의 호환을 이룰 수 있다.

• 한국신재생에너지학회:학술대회논문집
• /
• 2010.06a
• /
• pp.65.1-65.1
• /
• 2010

KPX(Korea Power Exchange) has been supervising FIT(Feed-in-tariff) for renewable energy power plants and supported 289MW photovoltaic power plants with Electric Power Industry Basis Fund in 2009. In this paper, we'll analyze utilization factor of these PV power plants in 2009 and for the latest 3 years and finally utilization factor of other renewable energy power plants in 2009.

• 한국신재생에너지학회:학술대회논문집
• /
• 2010.11a
• /
• pp.132.1-132.1
• /
• 2010

자원고갈과 지구온난화 등으로 재생에너지의 사용 및 보급이 지속적으로 증가할 것으로 예상되지만, 세계적으로 매장량이 풍부한 석탄의 사용량은 2030년 이후에도 지속적으로 증가될 전망이다. 따라서 세계 각국은 기후변화 규제에 대응하면서도 청정하게 석탄을 사용하기 위한 기술의 개발 및 보급을 활발히 진행 중이며, 국내에서도 온실가스 감축과 동시에 국가 성장 동력화를 추진하고 있다. 석탄가스화 기술은 석탄을 가스화하여 생산된 CO, $H_2$가 주성분인 합성가스를 연료로 활용하는 기술로, 이용 효율이 높고 석탄을 천연가스 수준으로 청정하게 사용할 수 있는 차세대 석탄이용 기술이다. 본 연구에서는 pilot급 석탄 가스화기에서 생산된 합성가스에 함유된 산성가스를 고온에서 건식으로 제거하는 시스템을 구축하였으며, 석탄 합성가스를 고온 건식 정제시스템에 공급하기 위한 석탄가스화기의 운전특성을 파악하였다.

• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.12 no.3
• /
• pp.447-455
• /
• 1999

An adaptive mesh generation scheme is developed for effective non-linear analysis of the shell structures under large deformation. In particular, based on a posteriori error estimation, remeshing method on each load step is of primary interest here. An advancing front method, called paving method, is adopted for remeshing. It can be known that the adaptive mesh generation using contours of spacing values obtained from stress errors has an advantage in the adaptive analysis of the shell structures.

• Proceedings of the KIPE Conference
• /
• 2016.07a
• /
• pp.457-458
• /
• 2016

최근 계통연계가 어려운 도서산간지역의 전력문제 해결방안으로 마이크로그리드가 해법으로 제시되고 있다. 신재생에너지 및 디젤발전으로 구성되는 마이크로그리드는 신재생자원의 간헐적인 출력 때문에 적정규모를 선정하는데 어려움이 있다. 본 논문에서는 신재생 에너지의 간헐적인 출력을 고려하여 HOMER프로그램을 이용하여 적정 규모를 선정하고 감도 분석을 통하여 최적점을 설계하고 실제로 운영되는 마이크로 그리드와 비교하여 한계점을 파악하고 이를 토대로 개선하는 방향으로 연구를 진행한다.

• 한국생물공학회:학술대회논문집
• /
• 2003.10a
• /
• pp.761-762
• /
• 2003

Recently, several studies have reported on the successful repair of osteochondral defects by transplantation of cultured chondrocytes, but the method requires a sufficient number of cells obtained from the donor site in the articular cartilage. This can potentially be overcome by the use of undifferentiated or partially developed cartilage precursor cells drived from early embryos and fetal tissue. Neonatal cartilage unlike adult cartilage has the capacity for rapid regeneration. the purpose of this study is to determine effective regeneration method using early cartilage precursors for tissue-engineered cartilage. Cells isolated from neonatal (immediately postpartum, 2 hours of age) SD rats were seeded onto biodegradable polymer matrices and transplanted in nude mice's subcutaneous sites for 4 and 8 weeks. Tissue-engineered cartilage showed gross and histologic evidences similar to native articular cartilage.