• Korea-Australia Rheology Journal
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• v.20 no.4
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• pp.245-251
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• 2008

Two polysiloxanes having different chemical structures were blended with polycarbonate (PC) under ultrasonic irradiation in solution. The polysiloxanes used were poly(methylphenyl siloxane) and vinyl-terminated poly(dimethyl siloxane). It was of primary interest to investigate the effect of polysiloxane structure on the rheological properties of PC/polysiloxane blends. It was found that a small amount (1.5 phr) of polysiloxanes greatly altered the melt viscosities and elasticity of PC. In particular, incorporation of poly(methylphenylsiloxane) led to a notable increase in elasticity with greater shear sensitivity of PC. The observed rheological behaviors of PC/polysiloxane blends were partly explained in conjunction with the tendencies found in ultrasonic degradation of polysiloxanes. Thermal stability and morphology in sonicated blends of PC/polysiloxane blends were also discussed.

• Journal of Biosystems Engineering
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• v.12 no.3
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• pp.50-56
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• 1987

중규모 벼농가에서의 벼건조 및 저장을 위하여, 한국형 개량곳간(크기: $1.8{\times}2.4m$, 높이 : 3.2m, 규모 : 2-4 M/T)을 개발하였다. 송풍기(0.5마력) 및 공기유도닥트를 부착하여 건조 및 aeration이 가능하도록 하였으며, 저장중 양곡손실을 최소한 줄이기 위해 방서용철망, 환풍창 및 구판들을 설치하였다. 그리고 양곡의 입출고가 용이하도록 내리닫이쪽문을 설치하였다. 개발된 개량곳간을 이용하여 1981년, 1982년, 1983년 가을에 각각 수확한 물벼를 수확즉시 건조하였을 때, 기후조건, 수확시기, 수확시의 수분함량, 풍량, 송풍시간, 곳간내에서의 벼의 높이 등에 따라서 차이는 있으나 상온 통풍에 의하여 벼를 잘 건조할 수 있었다. 그리고 건조조건에 따라서 건조양상은 달랐으나 180~352시간의 건조시간이 소요되었으며, 연속 상온통풍에 의하여 건조된 벼의 품질은 비교적 양호하였다.

• Journal of the Optical Society of Korea
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• v.9 no.2
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• pp.79-83
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• 2005

Spatial calibrations have been performed on the Medium-sized Aperture Camera (MAC) of the RazakSAT satellite. Topics discussed in this paper include the measurements of system modulation transfer function (MTF), relative pixel line-of-sight (LOS), and end-to-end imaging tests. The MTF measurements were made by capturing the scanned knife-edge image on a pixel, and an issue in the MTF calculation algorithm is discussed. The method used to place the focal plane at the correct focal position is described, since they make use of MTF measurements. Relative LOS measurements are done by theodolite measurements of the telescope. Qualitative ground test result of end-to-end imaging is given.

• Proceedings of the Korea Information Processing Society Conference
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• 2017.11a
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• pp.1244-1245
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• 2017

Using a small computer called Raspberry Pie, the webcam is interlocked with the webcam to detect the desired color using hsv and find the representative line using the hough transform in the detected color. Another new line is extracted and the coordinates where the lines meet are called the vanishing point and we want to make a system that autonomously travels through the vanishing point.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2013.05a
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• pp.109-110
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• 2013

Medium carbon steel was aluminized by hot dipping into molten Al or Al-1%Si baths. After hot-dipping in these baths, a thin Al-rich topcoat and a thick alloy layer rich in $Al_5Fe_2$ formed on the surface. A small a mount of FeAl and $Al_3Fe$ was incorporated in the alloy layer. Silicon from the Al-1%Si bath was uniformly distributed throughout the entire coating. The hot dipping increased the microhardness of the steel by about 8 times. Heating at $700-1000^{\circ}C$ however decreased the microhardness through interdiffusion between the coating and the substrate. The oxidation at $700-1000^{\circ}C$ in air formed a thin protective ${\alpha}-Al_2O_3$ layer, which provided good oxidation resistance. Silicon was oxidized to amorphous silica, exhibiting a glassy oxide surface.

• ETRI Journal
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• v.33 no.3
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• pp.374-381
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• 2011

A simple and effective compression method is proposed for multiple-scan testing. For a given test set, each test pattern is compressed from the view of slices. An encoding table exploiting seven types of frequently-occurring pattern is used. Compression is then achieved by mapping slice data into codewords. The decompression logic is small and easy to implement. It is also applicable to schemes adopting a single-scan chain. Experimental results show this method can achieve good compression effect.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.12
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• pp.1843-1847
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• 2012

Piezo devices have large power density and simple structure. They can generate larger force than the conventional actuators. It has also wide bandwidth with fast response in a compact size. Thus the piezo devices are expected to be used widely in the future for small actuators with fast response time and large actuating force. However, the piezo actuators need high voltage with high driving current due to their large capacitive property. In this paper, we propose a simple method to drive piezo devices using voltage inversion circuit with coil inductance. Experiments with real circuit demonstrates that the proposed scheme can improve the energy efficiency very much.

• Solar Energy
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• v.11 no.3
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• pp.9-20
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• 1991

Experiments for drying radish were carried out to analyze the drying characteristics and quality evaluation between solar heated-air drying and natural air drying system. Solar heated-air drying system consists of a small fan, a solar air heater and a tunnel dryer. Simulation model for thermal environments of solar collector was developed to investigate the effect of solar radiation and airflow rate on thermal performance.

• Transactions on Electrical and Electronic Materials
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• v.1 no.2
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• pp.1-6
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• 2000

This article presents the experiments and considerations possible about gate etching in polysilicon when oxygen gas is added in chamber, We propose the novel study with optical emission spectroscopy in polysilicon etching. It is shown that added oxygen gases play an important role in enhencement of density in chlorine gases as a scavenger of silicon from SiCl$\_$x/. And a small amount of Si-O bonds are deposited and then the deposited thin film protect silicon dioxyde against reaction chlorine with silicon in SiO$_2$. Consequently, we can improve the selectivity of polysilicon the silicon dioxide, which is clearly explained in this model.

• Earthquakes and Structures
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• v.17 no.1
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• pp.17-29
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• 2019

The present study aims to present a comprehensive understanding of the performance of neighboring multi-story buildings with different dynamic characteristics under blast loads. Two different scenarios are simulated in terms of explosion locations with respect to both buildings. To investigate the effect of interaction between the neighboring buildings in terms of the induced responses, the separation gap is set to be sufficiently small to ensure collisions between stories. An adequately large separation gap is set between the buildings to explore responses without collisions under the applied blast loads. Several blast loads with different peak pressure intensities are employed to perform the dynamic analysis. The finite-element toolbox Computer Aided Learning of the Finite-Element Method (CALFEM) is used to develop a MATLAB code to perform the simulation analysis. The dynamic responses obtained in the scenarios considered herein are presented comparatively. It is found that the obtained stories' responses are governed mainly by the location and intensity of the applied blast loads, separation distances, and flexibility of the attacked structures. Moreover, explosions near a light and flexible building may lead to a significant decrease in blast resistance because explosions severely influence the dynamic responses of the building's stories.