• Journal of the Korean Society of Safety
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• v.32 no.6
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• pp.9-15
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• 2017

Recently many researches were conducted on the interlaminar fracture that is a delamination between laminates by using ASTM standardized methods. However the experiment of the intralaminar a fracture is difficulty. In this study, four types of CFRP/GFRP composites with different layer structures were compared to evaluate an intralaminar fracture toughness under the mode I. Also the CNTs were added to the layer for the examination of the fracture toughness improvement. And the characteristics of the crack propagation behaviour was observed using a microscope. The obtained results can be useful for the evaluation of the intralaminar fracture toughness of the CNT reinforced CFRP/GFRP composites.

• Journal of the Korean Ceramic Society
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• v.31 no.11
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• pp.1323-1329
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• 1994

Tape casting and lamination were used to produce heterogeneous laminates with alternating layers of different porosity and homogeneous laminates with component layers of the same porosity. The pore structure was investigated for heterogeneous laminates, and bend strength was measured for comparison with that of homogeneous laminates. For a reference, strength measurement was made for the porous body fabricated by sintering samples dry-pressed at low pressure with spray-dried granules. Strength increase, in the range 50~120 MPa, was achieved in the presence of the surface dense layer, while extensive delamination, presumably responsible for enhanced fracture toughness, took place through the internal porous layer.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.2
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• pp.151-157
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• 2013

In this paper, properties of pattern using LBG (Linde-Buzo-Gray) Algorithm was explored including the exactness of K-means algorithm and process time of EM (Expectation Maximization) algorithm in order to develop analysis algorithm of partial discharge pattern in a cable using acoustic data analysis system. Partial discharge was measured by generating inner fault due to lamination of XLPE which is used for cable insulation material. Discharge pattern was analysed by changing the number of swarm article to 2, 4, and 6 in order to interpret swarm structure and properties.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.14 no.1
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• pp.11-19
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• 2001

기능경사재(FGM)는 구성 물질의 체적분율(volume fraction)이 복합재 전체에 걸쳐 연속적 그리고 기능적으로 분포되어 있어, 기존의 이종물질 접합식(bi-material-type) 복합재보다 현저히 우수한 열기계적 특성을 가진다. 하지만, 기능경사 내열복합재의 열-탄소성 거동은 체적분율의 분포형태와 경사층이 차지하는 상대두께비에 따라 절대적으로 좌우된다. 본 연구는 기능경사 내열복합재의 열-탄소성 특성의 이들 두 설계인자에 대한 파라메트릭 FEM해석을 다룬 것이다. 열-탄소성 이론과 유한요소 근사화에 따라 연구용 2차원 FEM 프로그램을 개발하고, 대표적인 3층 구조의 2차원 기능경사 내열복합재의 열-탄소성 특성을 설계변수의 다양한 조합에 따라 분석하였다.

• 한국태양에너지학회:학술대회논문집
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• 2012.03a
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• pp.102-107
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• 2012

The purpose of thesis is to improve output of solar cell module by enhancing transmission efficiency. To improve transmission efficiency, transmission interconnection ribbon which is used to connect solar cells and busbar which contacts with it has been improved. To secure reliability, comparison research on output of solar cell modules has been conducted by manufacturing PCB module formed by laminated metal with the same output. The result of this research is based on a output efficiency test of modules by comparing electric conductivity of soldering busbar and laminated PCV type of busbar.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.251-251
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• 2010

Organic-inorganic hybrid materials have attracted because of its combined properties, such as flexibility and high electrical performance. In addition, the hybrid materials are expected to have synergic effect which are not shown in just one component. Here, we fabricated organic-inorganic hybrid thin film. Organic-inorganic hybrid thin film have been deposited from diethyl zinc and 1, 2, 4-trihydroxybenzene (THB) by molecular layer deposition (MLD). UV-VIS, Using Infrared spectrum and X-ray photoelectron spectroscopy confirm that Zinc and THB hybrid film (ZnTHB) consist of Zn-O and THB - oxide units and the micro structure and composition of hybrid film. hat the sequential surface reactions of diethyl zinc and ethylene glycol are sufficiently self-limiting and saturating to enable well-controlled MLD growth. Transmission electron microscopy image shows lamination growth of ZnTHB film according to cycle.

• Proceedings of the KIEE Conference
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• 1994.07a
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• pp.79-81
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• 1994

A solution of magnetic fields for amorphous core transformer has been tried using homogenization technique. The technique, which is derived by applying asymptotic expansion to the standard finite element method, is helpful to analyse a joint part of amorphous core transformer microscopically. A butt-lap-step joint type of lamination method is modeled and its equivalent reluctivity is calculated to analyse various quantities of the magnetic fields. The algorithm is also applicable to other electric devices which have complicated material structure with repeated patterns.

• Proceedings of the KIEE Conference
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• 1997.07a
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• pp.51-53
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• 1997

Even though, many types of induction motors are known, most of the single phase induction motors being used are of squirrel cage type. However, basic structure of the machine has not been changed a lot during the past century. Author had been experienced many experiments with modified rotor. The modification was completed by doing two procedures: an elimination of lamination in central pan of the rotor and filling of melted aluminium in it instead. This paper demonstrates the reason for higher efficiency.

• Journal of Industrial Technology
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• v.29 no.A
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• pp.177-182
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• 2009

The inductor which is used at low frequency as the main part of magnetic ballast consists of an iron core, a bobbin and coil. The conventional inductor design method is not suitable for the magnetic ballast because it has various variables and is not a unique method for the magnetic ballast. Thus, this paper presents the optimal design method for a lamination type inductor using a magnetic ballast for Metal Halide Lamps. Also, the optimal inductor design method is researched for inductors of dimming ballasts and ignitors that have a gate-triggered structure using a SCR thyristor. By the simulation and experimental results, we showed that the proposed design methods is valid.

• Proceedings of the KIEE Conference
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• 2000.07b
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• pp.675-677
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• 2000

In the paper the eddy current loss in brushless DC motor due to switching frequency supplied by PWM inverter, is analyzed. The compensated conductivity is used in order to analyze the eddy current loss in brushless DC motor which has lamination structure. The eddy current loss is deceased when switching frequency supplied by PWM inverter is gradually increased from 1.2kHz up to 12kHz. The high switching frequency of PWM inverter make the output wave into a similar sine wave and this leads to the decreasing eddy current loss.