• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2000.04a
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• pp.165-174
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• 2000

새로운 에너지원으로 개발된 오리멀젼의 국내 활용에 관한 기술적인 특성을 파악하기 위하여 연료 특성과 연소에 대한 실험적인 연구를 수행하였다. 연료저장을 위한 최적온도는 6$0^{\circ}C$이었으며 온도가 낮으면 점화특성이 불량하고 너무 상승하는 경우에는 계면분리 현상이 보였다. 연소를 위해 필요한 연소실온도는 $600^{\circ}C$ 이상이 요구되었고 수분의 비등폭발에 의해 2차 연소가 특징적으로 관찰되었다. 오리멀젼 연소시 배기가스중 오염물질 농도는 과잉공기비에 SO$_2$ 가 1700-2200ppm , NOx 100-150ppm 으로 측정되었다.

• Proceedings of the KIEE Conference
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• 1988.07a
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• pp.595-598
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• 1988

In this paper, a new folding algorithm for design of high density PLA's is proposed. This algorithm generates transform matrix so that programmed region of each row becomes narrow. Based on transform matrix, folding pair is selected. In the process of generating transform matrix, interval degree and dense degree are used to improve folding ratio. This paper also proposes an efficient folding pair graph which has short time of selection folding pair. This proposed algorithm is named PLAFOLII and implemented in C language on VAX-11/750 (UNIX) computer. Through various example, efficiency of this algorithm is verified.

• Proceedings of the KIEE Conference
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• 2001.04a
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• pp.57-59
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• 2001

This paper presents the shape optimization to minimize the BEMF(Back Electro-Motive Force) harmonics of PM type synchronous generators. RSM(Response Surface Methodology) is used to find the optimal solution. We used the 2D-Finite Element Method to obtain the observed data of the BEMF and SQP(Sequential Quadratic Problem method) is used to solve the constrained nonlinear optimization problem.

• Proceedings of the Optical Society of Korea Conference
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• 2003.02a
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• pp.86-87
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• 2003

TiO$_2$ 박막은 높은 유전율과 우수한 화학적 안전성, 가시광선 영역에서 우수한 투과성 및 높은 굴절률을 가지고 있어 광범위한 분야에 중요한 물질로써 사용되어져 왔다. 일반적으로 TiO$_2$는 rutile, anatase, brookite의 세 가지 결정형태를 가진다. 이런 TiO$_2$ 박막을 제작하기 위해 sputtering, e-beam evaporation, sol-gel method, chemical vapor deposition(CVD) 등과 같은 물리적, 화학적인 방법이 이용되고 있다. 이러한 제조방법들 중에서 스퍼터링 방법은 박막을 형성하는 이온들의 이온에너지를 높여주어 덩어리에 가까운 성질을 가지기 때문에 조밀한 박막을 제작하는데 이용되며, 박막의 대면적 코팅과 표면 경도가 우수한 박막을 제작할 수 있는 장점을 가지고 있다. (중략)

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.10
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• pp.1002-1008
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• 2001

The energy is the basis for almost all industrial activities and domestic needs. But recently there are increasing concerns internationally over environmental problems and consequent climate changes caused by the excessive use of fossil fuels. Furthermore the price of crude oil is increasing steadily with unstable supplies. In order to solve these national energy problems, the utilization of Ocean Energy is introduced as one of the best alterative technologies for the future. OTEC Power Plant has been installed at the West Inchon Power Plant Site. Temperature differences of$20~25^{\circ}C$ been utilized for plant operations, where R22 is used as a working fluid. The system is composed of low pressure turbine, plate type heat exchanger, and pumps. In the present investigation the experimental results, such as gross power, net power and objective function, are analysed when temperature differences change from the reference design point.

• Journal of the Korean Society of Safety
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• v.7 no.1
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• pp.13-19
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• 1992

Supercritical fluid technology was applied to the regeneration of industrial catalyst contaminated with toxic materials. The regeneration process of activated loaded with phenol was proposed, then the adsorphon tower was packed with the activated carbon-bed. Phenol diffuses into supercritical carbon dioxide(SCC) through the micro-pore and voldge of the activated carbon. The saturated solubility of phenol in SCC depended on the density of SCC varing with temperature and pressure conditions. Therefore, the fasile phase equilibrium calculation model of dxpanded liquid One was proposed, and equilibrium solubility of phenol in SCC was calculated using the model theoretically. The regeneration mechanism of activated carbon was analysed by degree of saturation of phenol and diffusion in SCC. The solubility prediction was more satisfactory for the wide range of SCC density than the dense gas model and the desorption of phenol depended on the degree of saturation of phenol in SCC.

• Korean Journal of Optics and Photonics
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• v.8 no.3
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• pp.204-208
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• 1997

We analyze the intensity characteristics of the output beams of the ring laser, in which only one mode is generated in each direction, within the neoclassical model by using the Maxwell-Bloch equation. Considering the Nd:YAG crystal as a gain medium, we investigate the stability and the modulation of the output beam intensity as the pumping rate, the relaxation or the decay rate, and the frequency detuning vary, upon taking into account the effect of the beam in one beam in one direction onto the beam in the other direction. In particular, we examine the variation of the output beam intensity and the stability condition through a computer simulation.

• The Korean Journal of Ecology
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• v.21 no.5_3
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• pp.687-694
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• 1998

In this study, the occurrence and distribution of dictyostelid cellular slime molds was investigted from soils of typical forests in Mt. Nam and the effect of soil environmental factor on cellular slime molds was investigated. The fourteen species including two undescribed species were isolated as follows: Dictyostelium brefeldianum, Polysphondylium pallidum, P. violaceum, P. pseudo-candidum in Quercus mongolica-Sorbus alnifolia forests, D. purpureum, D. mucoroides var. stoloniferum, D. dimigraformum, D. brefeldiamum, P. pallidum, P. tenuissimum, P. violoceum, P. candidum, P. pseudo-candidum in Pinus densiflora forests, D. polycephahum, D. capitatum, d. brefeldianun, P. candidum in Robinia pseudo-acacia forests, D. purpureum, D. aureostipes var, aureostipes, D. polycephalum in Quercus acutissima forests, D. minutum, D. implicatum. in the site disturbed by human. The dominant species were P. pallidum, D. brefeldiamum, P. pseudo-candidum and D. dimigraformum were the undescribed species in Korea. Environmental factors such as soil pH, water content, organic content, total nitrogen and total phosphorus made a little effect on total species number, the number of clones.

• Journal of Intelligence and Information Systems
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• v.1 no.1
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• pp.123-134
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• 1995

인공신경망을 이용한 기업도예측에 관한 연구는 일반적으로 대기업을 대상으로 수행되고 있으며, 분석자료로는주로 재무제표에서 얻어지는 재무정보를 사용하고 있다. 이들 대기업의 재무정보들은 비교적양이 풍부하고 신뢰성이 높기 때문에 인공신경망을 이용한 도산예측의 적중률이 80%∼85%의 높은 수준을 보이고 있다. 하지만, 중소기업이 재무정보는 불충분할 뿐만 아니라 신뢰성이 낮을 가능성이 높기 때문에, 중소기업의 도산예측에 있어서 재무정보만을 사용하게 되면 그 정확도가 떨어지게 된다. 본 연구에서는 인공신경망을 이용한 중소기업의 도산예측에 있어서, 재무정보를 보완할 수 있는 비재무정보의 유용성을 검증하였다. 연구결과 본 연구에서 사용한 비재무정보가 획득가능한 비재무정보중 극히 일부에 지나지 않았음에도 불고하고, 재무정보만을 사용하였을 때보다 예측력이 10%정도나 향상되었다.

• Journal of Intelligence and Information Systems
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• v.3 no.2
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• pp.33-55
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• 1997

A data model is a diagram that describes the properties of different categories of data and the associations among them within a business or information system. In spite of its importance and usefulness, data modeling activity requires not only a lot of time and effort but also extensive experience and expertise. The data models for similar business areas are analogous to one another. Therefore, it is reasonable to reuse the already-developed data models if the target business area is similar to what we have already analyzed before. In this research, we develop a case-based reasoning system for data model reuse, which we shall call CB-DM Reuser (Case-Based Data Model Reuser). CB-DM Reuse consists of four subsystems : the graphic user interface to interact with end user, the data model management system to build new data model, the case base to store the past data models, and the knowledge base to store data modeling and data model reusing knowledge. We present the functionality of CB-DM Reuser and show how it works on real-life a, pp.ication.