• Defense and Technology
• /
• no.12 s.154
• /
• pp.28-31
• /
• 1991

최근의 경제환경은 대내외적으로 걸프전의 영향, 국제통상마찰의 가중 및 EC지역 통합이 확대되고 있어 우리 경제의 앞날을 어둡게하고 있습니다. UR등 개방화, 자율화 압력의 가중으로 우리경제의 개방화, 국제화는 더욱 급속하게 진전되고 있으며, 이로 인해 취약한 국내산업에 대책마련이 시급한 실정에 있습니다. 우리경제의 전환기를 맞아 새로운 도약과 내실화를 위해서는, 우리의 방위산업도 재정립을 모색하여 보다 적극적으로 육성, 추진되어야 할 시점이라 하겠습니다

• The Microorganisms and Industry
• /
• v.18 no.3
• /
• pp.10-22
• /
• 1992

퇴비화는 유기물이 생물의 작용에 의해 분해되면서 보다 안정화된 형태로 변형되어 가는 과정으로 여러가지 환경요인에 의해 영향을 받는다. 본 논문에서는 유기물의 퇴비화 과정에 영향을 주는 요인을 토양 생화학적 및 미생물학적 측면으로 분석하여 퇴비화 공정설계에 있어 분해원리의 이해에 도움을 주고자 하며, 퇴비화 후 최종적인 사용, 즉 농업적 이용 가능성에 대해서도 간략하게 기술하고자 한다.

• ETRI Journal
• /
• v.9 no.3
• /
• pp.115-126
• /
• 1987

자연화(Natural Image)는 CCITT SG Vlll에서 통용되는 기술용어로서 정지된 컬러 영상(Still Full Color Image)을 의미한다. 자연화는 많은 정보를 내포하고 높은 신뢰도를 갖기때문에 자연화 통신기술의 중요성이 날로 증대되고 있다. 본고에서는 자연화 통신에 필요한 영상정보 압축기술의 현황을 분석하고 또한 국제표준화 기술동향을 설명하였다.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.36 no.6
• /
• pp.639-646
• /
• 2012

The characteristics of autoignited lifted flames in laminar jets of carbon monoxide/hydrogen fuels have been investigated experimentally in heated coflow air. In result, as the jet velocity increased, the blowoff was directly occurred from the nozzle-attached flame without experiencing a stabilized lifted flame, in the non-autoignited regime. In the autoignited regime, the autoignited lifted flame of carbon monoxide diluted by nitrogen was affected by the water vapor content in the compressed air oxidizer, as evidenced by the variation of the ignition delay time estimated by numerical calculation. In particular, in the autoignition regime at low temperatures with added hydrogen, the liftoff height of the autoignited lifted flames decreased and then increased as the jet velocity increased. Based on the mechanism in which the autoignited laminar lifted flame is stabilized by ignition delay time, the liftoff height can be influenced not only by the heat loss, but also by the preferential diffusion between momentum and mass diffusion in fuel jets during the autoignition process.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.11 no.5
• /
• pp.56-61
• /
• 2012

Several Visualization techniques have been applied in traffic information area. This work is the basic research for applying of interactive visualization techniques when the traffic information is provided to users. Design of interactive visualization techniques were applied to traffic information services. Previous studies for information visualization with interactive visualization techniques were investigated, and the traffic information services currently provided were analyzed. There are many types of interactive visualization techniques, but this study is mainly focused on selecting, querying, linking, filtering and rearranging techniques. The users can obtain the proper and more suitable information for theie needs, because each interactive visualization techniques support interaction between information and users. The traffic information which has one of interactive techniques can be more effective for decision making and utilization. More attention is given to interactive visualization of data and information techniques in transportation field. By this research, it is expected that traffic information services is more effective and can be a foundation work for various interactive visualization techniques in traffice inforamtion.

• Management & Information Systems Review
• /
• v.36 no.1
• /
• pp.143-159
• /
• 2017

The purpose of this study examined the relationships between planned obsolescence and replacement purchase intention. This study also analyze the moderating effect of consumer innovativeness use on the relationship of planned obsolescence and replacement purchase intention. From total 205 survey analysis, this study finds the positive relationship planned obsolescence and replacement purchase intention. The result of analysis indicated that the functional obsolescence had positive effects on replacement purchase intention. The result of analysis indicated that the economic obsolescence had positive effects on replacement purchase intention. The result of analysis indicated that the psychological obsolescence had positive effects on replacement purchase intention. The result also shows that consumer innovativeness had a moderating effect on the relationship between planned obsolescence and replacement purchase intention. Finally, this study concluded with a discussion of the implications of the research findings and directions for future research.

• KSBB Journal
• /
• v.10 no.1
• /
• pp.9-14
• /
• 1995

Continuous production of fructooligosaccharides from sucrose by a dual immobilized enzyme system of fructosyltransferase and glucose isomerase was studied in a column reactor. The optimal temperature and pH of the immobilized fructosyltransferase were $65^{\circ}C$ and 5.5, respectively. The activity of glucose isomerase was favorable as temperature and pH were increased within the ranges examined. However, both the immobilized enzymes were thermally unstable over $5^{\circ}C$, suggesting that long-term operation of the dual immobilized enzyme column should be carried out below $50^{\circ}C$. The optimum packing ratio of fructosyltransferase to glucose isomerase was found to be around 5/3. Under the optimized reaction conditions, the dual enzyme column was successfully operated for 40 days without any loss of initial enzyme activities, yielding 66% of fructooligosaccharides. Furthermore, the relative sweetness of fructooligosaccharides produced by a dual emzyme system was enhanced by 6% compared with that of fructosyltransferase alone.

• 한국신재생에너지학회:학술대회논문집
• /
• 2008.05a
• /
• pp.345-348
• /
• 2008

본 연구에서는 가스화 반응, 수성가스 전환 반응, 메탄화 반응 등으로 구성된 SNG제조 공정에 대한 해석을 통해, 석탄 촤의 가스화 반응에 의해 생성된 합성가스를 이용한SNG제조 공정 특성을 파악하고자 하였고, SNG제조 공정 중 가스화 공정에 대한 실험을 통해 가스화 공정의 조건에 따른 합성가스 발생 특성 및 메탄화 반응의 특성을 살펴보았다. 석탄 촤를 대상으로 하여 가스화 공정의 $O_2$/feed ratio와 steam/feed ratio 조건 변화에 따른 합성가스 발생 특성을 살펴본 결과 steam을 투입하지 않은 경우 발생되는 합성가스 중 CO의 농도는 55$\sim$65%, $H_2$ 9$\sim$11%, $CO_2$ 24$\sim$29% 범위였고, $O_2$/feed ratio가 증가할수록 CO의 농도는 증가하고, $H_2$와 $CO_2$의 농도는 감소하는 경향을 나타내었다. 또한,steam을 투입하는 경우 합성가스 중 CO의 농도는 20$\sim$37%, $H_2$ 16$\sim$18%, $CO_2$ 42$\sim$55% 범위였다. 메탄화 공정 해석 결과 메탄의 농도를 최대로 얻을 수 있는 조건은 $H_2$/CO 비가 3인 조건이었고 온도가 낮을 수록 생성농도가 높아짐을 알 수 있었다. 가스화 특성 실험 결과 및 공정해석 결과, 메탄화 반응에 대한 실험 및 공정해석 결과는 고체시료의 가스화 반응을 통해 발생한 합성가스를 이용한 SNG 제조 공정 특성 파악 및 SNG를 제조하기 위해 필요한 단위 공정에 대한 설계 자료 및 운전조건을 결정할 수 있는 주요 인자로 활용될 수 있을 것으로 판단된다.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.23 no.5
• /
• pp.1299-1309
• /
• 1998

In this paper, we propose a new approach for reducing the blocking artifact that is one of drawbacks of the block-based Discrete Cosine Transform (DCT) without introducing additional information or significant blurring. We modify the inter-block discontinuity minimization technique to preserve edges within a block as well as to reduce visible block boundaries. The homogeneity of each block is decided by the threshold value reated to Q-factor, which is included in a JPEG as well as MPEG streams. The quantization error is estimated by minimizing the discontinuity, which is weighted in proportion to block discontinuity and added to each pixel in the block to compensate block artifacts. The proposed algorithm reconstructs images which have less noticeable block boundaries from a subjective viewpoit without anyconstraints.

• Korean Chemical Engineering Research
• /
• v.43 no.5
• /
• pp.566-570
• /
• 2005

The study on the hydrogenation and isomerization of unsaturated bicyclic hydrcarbon compounds using methylcyclopentadiene dimer (MCPD) was carried out. Exo compound was prepared through isomerization reaction after two hydrogenation reaction steps. In the first hydrogenation reaction which needs one mole of hydrogen, the formation rate of monomer was increased as dimer was decomposed at reaction temperature above $100^{\circ}C$. At first hydrogenation, DHDMCPD [dihydrodi(methylcyclopentadiene)] was formed and second hydrogenation was proceeded to produce THDMCPD [tetrahydrodi(methylcyclopentadiene)], the ratio of exo to endo THDMCPD was varied by the control of 2nd hydrogenation temperature. To improve the process, continuous 1st and 2nd hydrogenation conditions were established by using the 2nd stage heat controllable reactor. Also, catalytic activities were compared by the use of halogenized aluminum, metal halides and solid acids catalysts on the isomerization reaction from endo to exo THDMCPD.