• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.208-209
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• 2006

This study presents the thermal stress characteristics of TL porcelain insulators(healthy and ageing) by the accelerating thermal mechanical ageing test with forced temperature gradient. The test temperature gradient is $95^{\circ}C(-35{\sim}60^{\circ}C)$, it was focused to high temperature thermal stress as compared with IEC 60575 standard. There was no a discrimination in the case of healthy aluminous porcelain insulators, dissimilarly in crystoballite insulators according to this test method. It was indicated that the long tenn reliability by thermal stress was conformed reasonably through the conventional accelerating ageing test methods.

• Nuclear Engineering and Technology
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• v.39 no.5
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• pp.637-646
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• 2007

An UET (ultrasound excited thermography) has been used for several years for a remote non-destructive testing in the automotive and aircraft industry. It provides a thermo sonic image for a defect detection. A thermograhy is based On a propagation and a reflection of a thermal wave, which is launched from the surface into the inspected sample by an absorption of a modulated radiation. For an energy deposition to a sample, the UET uses an ultrasound excited vibration energy as an internal heat source. In this paper the applicability of the UET for a realtime defect detection is described. Measurements were performed on two kinds of pipes made from a copper and a CFRP material. In the interior of the CFRP pipe (70mm diameter), a groove (width - 6mm, depth - 2.7mm, and length - 70mm) was engraved by a milling. In the case of the copper pipe, a defect was made with a groove (width - 2mm, depth - 1mm, and length - 110 mm) by the same method. An ultrasonic vibration energy of a pulsed type is injected into the exterior side of the pipe. A hot spot, which is a small area around the defect was considerably heated up when compared to the other intact areas, was observed. A test On a damaged copper pipe produced a thermo sonic image, which was an excellent image contrast when compared to a CFRP pipe. Test on a CFRP pipe with a subsurface defect revealed a thermo sonic image at the groove position which was a relatively weak contrast.

• Journal of Korean Elementary Science Education
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• v.37 no.4
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• pp.363-371
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• 2018

The purpose of this study was to analyze the effects of wearing lab coats on science-related attitudes of elementary school students in science learning. In addition, we analyzed the effects of wearing lab coats on perceptions of the authenticity of school science activities and the necessity of wearing lab coats. Samples of the study were composed of 4 classes of 92 fifth graders in Seoul, Korea. Unit of 'Temperature and Heat' was selected as a object of the research. The major results of the study are as follows. First, for the independent t-test of science-related attitudes, a statistically significant difference between the experimental group and the comparative group was found. Second, 9 students (9.78%) were more than 1SD above the average of the difference between the results of pre and post. Seven of them were experimental group students and two were comparative group students. Third, there was a statistically significant difference between the comparison group and the experimental group as a result of the perception test of the similarity of the scientific activity of the elementary school students and the scientific activity of the scientists. Fourth, there was no statistically significant difference between the comparison group and the experimental group as a result of the perception test of the necessity of wearing a lab coat. Based on these findings of this study, implications for science education research and teaching and learning at school are discussed.

• Journal of the Korea Society of Computer and Information
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• v.26 no.9
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• pp.105-114
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• 2021

ESICD(Electrical Signal Interface Control Document) refers to a document that describes protocols and data for communication between components consist of a system. Each component developer gathers at a specific place to conduct an integrated test for ESICD verification. In this case, it often happens that the integration test is delayed due to a simple mistake of software developers. There are two reasons for this situation: First, software developers do not perform sufficient verification because it is difficult to configure the system environment in a Lab, and second, they do not immediately find the cause of errors occurred during integration tests. Therefore, in this paper, we propose a strategy to effectively perform ESICD verification, which takes a lot of time between the production and implementation stage of the weapon system development stage and the system integration test stage.

• Proceedings of the Korean Information Science Society Conference
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• 2010.06a
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• pp.293-294
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• 2010

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2007.04a
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• pp.129-146
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• 2007

[ ${\square}$ ] A mathematical model has been developed and used to analyze the limits of He fine leak test. ${\square}$ Uncertainties inherent in using the MIL-STD-883 guidelines for hermeticity evaluation of small packages have been demonstrated. ${\square}$ A new methodology to quantitatively characterize hermeticity has been developed.

• Bulletin of the Korean Chemical Society
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• v.25 no.6
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• pp.878-880
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• 2004

Revered-phase LC-electrospray ionization mass spectrometry was used to selectively determine enalapril from plasma with minimal sample preparation. Detection limit of the method was 1 ng/mL. Precision (within day and between days) and accuracy of the method at various concentrations were acceptable. The analytical technique was used for pharmacokinetic studies after administration of enalapril to human test subjects.

• Proceedings of the Korean Information Science Society Conference
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• 2010.06b
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• pp.414-418
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• 2010

많은 분야에서 사용되는 matlab을 이용한 test방식을 좀 더 유연하고 원하는 기능을 만들어 사용하기 위해 matlab의 데이터 저장 파일인 mdl 파일의 내부 구조를 분석하고 구문 분석기로 파싱하여 실행 가능한 그래프를 나타내는 자료구조를 만든다.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.356-358
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• 2004

In this paper we fabricated and succeeded to demonstrate a test panel for AMOLED on 2" glass and PET substrate. The test panel consisted of an array of 64 x 64 pixels in which OLEDs was driven by pentacene TFT. OTFTs were made of the inverted staggered structure and employed polyvinylphenol as the gate insulator and pentacene thin film as the active layer, producing the filed effect mobility of 0.3$cm^2$/V.sec and on/off current ratio of $10^5$. OLEDs were composed of TPD for HTL and Alq3 for EML with 35nm thick each, generating green monochrome light.

• Journal of Astronomy and Space Sciences
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• v.25 no.4
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• pp.347-360
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• 2008

In this paper, a Hardware-In-the-Loop simulator to simulate attitude control of space craft using momentum wheels is developed. The simulator consists of a spherical air bearing system allowing rotation and tilt in all three axes, three momentum wheels for actuation, and an AHRS (Attitude Heading Reference System). The simulator processes various types of data in PC104 and wirelessly communicates with a host PC using TCP/IP protocol. A simple low-cost momentum wheel assembly set and its drive electronics are also developed. Several experiments are performed to test the performance of the momentum wheels. For the control performance test of the simulator, a PID controller is implemented. The results of experimental demonstrations confirm the feasibility and validity of the Hardware-In-the-Loop simulator developed in the current study.