• 전기의세계
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• v.28 no.10
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• pp.35-40
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• 1979

최적전력조류계산 앨고리즘에서 분할최적전력조류계산 앨고리즘을 유도하였고, 주요점은 적정스텝의 결정과 부등식제약조건을 사용치 않은 점이다. 실규모계통에 지용하여 약0.5[%]의 비용절감을 달성하였는바, 이것은 년 약30억[원]에 해당되며, 겸하여 온라인운전의 가능성을 제시하였다.

• The Korea Swine Journal
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• v.23 no.5 s.261
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• pp.153-156
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• 2001

• The Korea Swine Journal
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• v.20 no.3 s.223
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• pp.116-120
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• 1998

• Journal of the Computational Structural Engineering Institute of Korea
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• v.33 no.6
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• pp.375-382
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• 2020

Owing to the rapid development of infrared guided weapon systems, the threat to aircraft survivability is constantly increasing, and research on infrared stealth technologies are being conducted to ensure aircraft survival. In this study, we analyze the minimum infrared signature of an aircraft according to its flight altitude by considering the characteristics of infrared guided missiles, which detect the contrast signature between the aircraft and background. We conducted computational fluid dynamics simulations for the convective coefficient, and heat transfer simulations were performed considering convection, conduction, and radiation for flight conditions. Thus, we obtained the surface temperature distribution of the aircraft and analyzed the aircraft infrared signature based on the flow characteristics around it. Furthermore, the optimum emissivity for the minimum infrared signature was derived, and the effect of the infrared signature was analyzed when this optimum emissivity was applied to the fuselage surface for each flight condition.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.6
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• pp.914-919
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• 2000

A simple orthogonal mode transducer(OMT) for X-band has been proposed in this paper. This OMT is designed such that a polarized wave can be guided in a direction using several thin guiding posts, and the other orthogonally polarized wave can be guided in the other direction using other thin guiding posts. The OMT consists of a T-shaped waveguide section with guiding posts, two tapering waveguide arms, and has three flanges for connection with two adapters and an antenna. The optimum numbers and the optimum positions of the guiding posts were obtained numerically using the HFSS CAD tool. The isolation between two polarizations in a manufactured OMT is higher than 42.8 dB and the reflection from the OMT is lower than -17.5 dB at the frequency band of 9.5 GHz

• Korean Journal of Medicinal Crop Science
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• v.14 no.4
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• pp.225-228
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• 2006

To acquire the normal regeneration of plantlets, we investigated combinations and concentrations of plant growth regulations for optimal conditions of adventitious root formation. Based on the previous study, we performed callus and shoot induction. When induced shoot was transferred into a rooting medium containing plant hormones, it wilted and died. Thus, the shoot proliferated on 1/2 MS medium for 10 days and was then treated with MS medium supplemented with 3.0 mg/L NAA for 3 days. Adventitious root formations were observed after shoot planlets were transferred to 1/3 MS medium. The concentrations of salt and sucrose were gradually reduced in MS medium and the rooted plantlets were transferred for acclimatization into a mixture of peatmoos : perlite (3 : 2).

• KSCE Journal of Civil and Environmental Engineering Research
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• v.12 no.3
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• pp.1-15
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• 1992

A Practical and easily applicable methods for the numerical analysis and the optimum design of continuous and horizontally curved two-way slab systems with twelve possible edge conditions are presented. The proposed method for the numerical structural analysis is based on the use of design moment coefficients which are derived from the elastic theory of thin curved plates. The optimum values are selected from within the feasible region in the design space defined by the limit state requirements. The sequential linear programming is introduced as an analytical method of nonlinear optimization. The optimum design variables, including a effective depth and transformed steel ratios per unit width of middle and column strips of slabs, are then determined.

• Journal of the Korean Institute of Intelligent Systems
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• v.10 no.3
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• pp.232-241
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• 2000

This study suggests an integrated method based on concept hierarchies, information gain, and rough set theory for efficient discovery rules from a large amount of data, and implements an optimal rules discovery system. Our approach applies attribute-oriented concept ascension technique to extract generalized knowledge from a database, knowledge reduction technique to remove superfluous attributes and attribute values, and significance of attributes to induce optimal rules. The system first reduces the size of database by removing the duplicate tuples through the condition attributes which have no influences on the decision attributes, and finally induces simplified optimal rules by removing the superfluous attribute values by analyzing the dependency relationships among the attributes. And we induce some decision rules from actual data by using the system and test rules to new data, and evaluate that the rules are well suited to them.

• Journal of the Korean Magnetics Society
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• v.8 no.3
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• pp.169-177
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• 1998

In the case of an induction motor efficiency optimal design for electric vehicle which is a real world problem, several different designs are almost equal in terms of efficiency. But these designs may have the differences in terms of other characteristics such as power factor, temperature rise, material cost, and ease of manufacture. Therefore it is necessary that an optimization routine suggests various possible solution alternatives and a designer selects optimal solution among them using other characteristics, his experience and judgment. In this paper new niching genetic algorithm and the rating function method to select the optimal point among possible optimal solution alternatives are presented.

• Transactions of the Korean Society of Mechanical Engineers
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• v.11 no.3
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• pp.437-443
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• 1987

An optimal design to improve the ride quality was performed with the time and frequency domain analysis based on both of deterministic and random road profiles. The objective function is established to minimize the absorbed power while the constraints are taken so as to satisfy the condition for the stability of vehicle. The result of the optimal design shows that the rms for the acceleration of a driver and his seat is within the critical values for the ride quality from ISO. The optimal values obtained show that the maximum absolute acceleration of the driver and his seat has significantly been reduced and the reference limits on the relative displacement have satisfied their feasibility. As the optimal value according to a specific speed is the results from the optimization process, a global optimum value should be determined to be the one which gives th minimum values of total sum of absorbed power with respect to various speed.