• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.1578-1580
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• 2000

전국적으로 사용되고 있는 배전용 주상변압기가 '91$\sim$'98년 동안 배전선로 설비별 고장원인 중 점유율이 9.8 %에 달하고 있어 이로 인한 불시 정전으로 고객의 피해와 민원이 발생하고, 전력회사의 신뢰를 실추시키고 있어 지속적으로 배전용 주상변압기의 품질 확보를 위한 노력이 요구되고 있다. 본 연구는 주상 변압기에 사용되고 있는 가스켓에 대한 성능확인 시험을 실시하여 가스켓의 특성을 살펴보고 불량요인을 찾아내어 신뢰성이 높은 변압기가 제작 될 수 있도록 하고자하는 내용이다.

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.3094-3096
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• 2000

In the distribution systems, there are generally two sources of transient over-voltages. One is the capacitor switching surge and the other is the lightning surge. This paper is written about the measuring and analysis of switching over-voltages in the 22.9 kV multi-grounded distribution systems. The measurement was performed in the Kochang distribution test line in January, 2000.

• Publications of The Korean Astronomical Society
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• v.25 no.4
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• pp.155-165
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• 2010

In this study, we investigate the changes in the equatorial lodge degrees and polar distance degrees of determinative stars in the ancient Chinese archives. Confirmed is the fact that the coordinate values of those determinative stars defined in B.C. 104 had been used until the 8th century but were modified by the observations of Li Chunfeng (李淳風) in the early 7th century and Yixing (一行) in 723 A.D. The results of this study are compared with those in History of Chinese Astronomical Observations of Pan Nai. By applying the results of comtemporary astrodynamical calculations, their reliability is checked, and the corrected catalogues of Shi Shi (石氏) and Yixing are provided. The positional accuracy of those observations is estimated to be one degree.

• 한국환경농학회:학술대회논문집
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• 2011.07a
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• pp.469-470
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• 2011

• Structural Engineering and Mechanics
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• v.8 no.2
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• pp.151-164
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• 1999

The large deflection theory of the Mindlin plate and Galerkin's method are employed to examine the static responses of a plate produced by the weight of the plate, and the dynamic responses of the plate caused by the coupling effect of these static responses with a set of moving forces. Results obtained by the large deflection theory are compared with those by the small deflection theory. The results indicate that the effect of weight of the plate increases the modal frequencies of the structure. The deviations of dynamic transverse deflection and of dynamic bending moment produced by a moving concentrated force between the two theories are significant for a thin plate with a large area. Both dynamic transverse deflection and dynamic bending moment obtained by the Mindlin plate theory are greater than those by the classical plate.

• Ocean Systems Engineering
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• v.12 no.2
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• pp.159-172
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• 2022

To ensure stable performance, adaptive regulators with new theories are designed for steel-covered offshore platforms to withstand anomalous wave loads. This model shows how to control the vibration of the ocean panel as a solution using new results from Lyapunov's stability criteria, an evolutionary bat algorithm that simplifies computational complexity and utilities. Used to reduce the storage space required for the method. The results show that the proposed operator can effectively compensate for random delays. The results show that the proposed controller can effectively compensate for delays and random anomalies. The improved prediction method means that the vibration of the offshore structure can be significantly reduced. While maintaining the required controllability within the ideal narrow range.

• International Journal of Internet, Broadcasting and Communication
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• v.15 no.1
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• pp.145-149
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• 2023

In this study, the spectrum changes induced from the doping of phosphor micro particles in a twist nematic liquid crystal cell was observed. The experimental results show that the achromatic transmission can be observed with a proper driving condition, which may be applied to the design of an achromatic liquid crystal device. In this paper, we tried to figure out the spectrum changes induced from the doping of phosphor micro particles. The experimental result of the phosphor powder doped twist nematic liquid crystal cell shows that the achromatic transmission and the wavelength linearly dependent transmission both can be observed with some proper driving conditions, respectively. The result is useful on developing an achromatic liquid crystal device and it can be applied for Vihicle lamp.

• Advances in aircraft and spacecraft science
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• v.9 no.2
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• pp.149-167
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• 2022

A Modified fuzzy mechanical control of large-scale multiple time delayed dynamic systems in states is considered in this paper. To do this, at the first level, a two-step strategy is proposed to divide a large system into several interconnected subsystems. And we focus on the damage propagation for aircraft structural analysis of composite materials. As a modified fuzzy control command, the next was received as feedback theory based on the energetic function and the LMI optimal stability criteria which allow researchers to solve this problem and have the whole system in asymptotically stability. And we focus on the results which shows the high effective by the proposed theory utilized for damage propagation for aircraft structural analysis of composite materials.

• International conference on construction engineering and project management
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• 2005.10a
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• pp.764-767
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• 2005

In the construction industry, materials management is one of the most important components in construction engineering life cycle. Materials management optimization is one of the research subjects in the field of construction management. In the materials management system of a construction project, the suitability of selecting procurement planning strategy will influence the result of project completion. This study conducts literature review at first and also refers the related issue in other industry's application. Associated with the characteristics of construction project in civil engineering and the concept of object oriented design applied in the materials management, this research is aimed to establish a construction materials requirement preliminary system.

• Coupled systems mechanics
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• v.12 no.3
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• pp.221-239
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• 2023

In our research, we have proposed a solid solution for aviation analysis which can ensure the asymptotic stability of coupled nonlinear plants, according to the theoretical solutions and demonstrated method. Because this solution employed the scheme of specific novel theorem of control, the controllers are artificially combined by the parallel distribution computation to have a feasible solution given the random coupled systems with aviation stability analysis. Therefore, we empathize and manually derive the results which shows the utilized lemma and criterion are believed effective and efficient for aircraft structural analysis of composite and nonlinear scenarios. To be fair, the experiment by numerical computation and calculations were explained the perfectness of the methodology we provided in the research.