• Journal of the Institute of Electronics Engineers of Korea SD
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• v.45 no.10
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• pp.39-44
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• 2008

Scan architecture is very effective design-for-testability technique that is widely used for high testability, however, it requires so much test time due to test vector shifting time. In this paper, an efficient scan test method is presented that is based on the Illinois scan architecture. The proposed method maximizes the common input effect via a scan chain selection scheme. Experimental results show the proposed method requires very short test time and small data volume by increasing the efficiency of common input effect.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.7
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• pp.57-66
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• 2009

Microturbines system (MTS) are currently being deployed as small scale on-site distributed generators for microgrids and smart grids. In order to fully exploit DG potentialities, advanced integrated controls that include power electronics facilities, communication technologies and advanced modeling are required. Significant expectations are posed on gas microturbines that can be easily installed in large commercial and public buildings. Modeling, control, simulation of microturbine generator based distributed generation system in smart grid application of buildings for both grid-connected and islanding conditions are presented. It also incorporates modeling and simulation of MT with a speed control system of the MT-permanent magnet synchronous generator to keep the speed constant with load variation. Model and simulations are performed using MATLAB, Simulink and SimPowerSystem software package. The model is built from the dynamics of each part with their interconnections. This simplified model is a useful tool for studying the various operational aspects of MT and is also applicable with building cooling, heating and power (BCHP) systems

• The Journal of Korean Institute of Communications and Information Sciences
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• v.17 no.12
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• pp.1484-1493
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• 1992

In this paper, we propose the polarization coding of optical logic gates using filters and LCTV's, and represent the real-time system of an optical parallel adder to improve a carry propagation delay time. We fabricated a polarization filter for the polarization coding of a cell and an electrical system instead of an optical flip-flop which was necessary to an optical parallel adder. We used an optical fiber to play a part of decoding mask and interconnections in an optical parallel adder. The experimental results show that the polarization coding of a cell can represent 16 optical logic functions and that the implemented optical parallel adder can operate in real-time.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11b
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• pp.230-233
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• 2001

FeSi2/Si Layer were grown using FeSi2, Si wafer by the chemical transport reactio nmethod. The directoptical energy gap was found to be 0.871eV at 300 K. The Hall effect is a physical effect arising in matter carrying electric current inthe presence of a magnetic field. The effect is named after the American physicist E. H. Hall, who discovered it in 1879. IN this paper, we study electrical properties of FeSi2/Si layer. And then we measured Hall coefficient Hall mobility, carrier density and Hall voltage according to variation magnetic field and temperature, Because of important part for it applicationVarious phase of silicide is formed at the metal-Si interface when transition metal contacts to Si. Silicides belong to metallic or semiconducting according to their electrical and optical properties. Metallic silicides are used as gate electrodes or interconnections in VLSI devices. Semiconducting silicides can be used as a new material for IR detectors because of their narrow energy band gap.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11b
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• pp.234-237
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• 2001

FeSi2/Si Layer were grown using FeSi2, Si wafer by the chemical transport reactio nmethod. The directoptical energy gap was found to be 0.871eV at 300 K. The Hall effect is a physical effect arising in matter carrying electric current inthe presence of a magnetic field. The effect is named after the American physicist E. H. Hall, who discovered it in 1879. IN this paper, we study electrical properties of FeSi2/Si layer. And then we measured Hall coefficient Hall mobility,carrier density and Hall voltage according to variation magnetic field and temperature, Because of important part for it applicationVarious phase of silicide is formed at the metal-Si interface when transition metal contacts to Si. Silicides belong to metallic or semiconducting according to their electrical and optical properties. Metallic silicides are used as gate electrodes or interconnections in VLSI devices. Semiconducting silicides can be used as a new material for IR detectors because of their narrow energy band gap.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.10
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• pp.923-930
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• 2003

We jointed Bi(Pb)-Sr-Ca-Cu-O multifilament tapes and evaluated their electrical and mechanical properties. In order to improve connectivity of multifilaments, one or two single-filament tape was inserted between two multifilament tapes. The critical current ratio(CCR) and n-value of the jointed tapes were evaluated as a function of uniaxial pressure. It was observed that critical current ratio and n-value were 24.8-29.0% and 2.5-2.8 for MM lap-jointed tape. On the other hand, the corresponding values were improved to 24.7-53.9% and 3.1-4.2 for MSM jointed tape, and 63.4-76.0% and 3.4-5.1 for double MS:vr lap-jointed tape, respectively. The highest electrical properties of double MSM lap-jointed tape are considered to be owing to the presence of single core, causing better interconnections of multifilaments between the two tapes. The mechanical property of jointed tape was evaluated and correlated to the microstructural evolution. The strength of jointed tapes was 44-64% less than that of the unjoined tape. The strain tolerance of jointed tape was also reduced compared to that of the unjoined tape. These lower mechanical properties of jointed tape are probably due to the induced nonuniform microstructure such as the existence of cracks and Ag-intrusion in the joined region.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2008.04a
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• pp.71-74
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• 2008

The main object of this paper is concentrated on distance control of two robot arms of a humanoid using Fuzzy Logic Controller (FLC) for handling a common object. Serial Link Robot arms are widely used in most significantly in Humanoids serving for older people and also in various industrial applications. A method is proposed here that separates the interconnections between two robot arms so that the resulting model of two arms is decomposed into fuzzy logic based controller. The distance between two end effectors is always kept equal to that of the diameter of an object to be handled, so that the object would not fall down. Mathematical model of this system was obtained to simulate the behavior of serial robotic arms in close loop control before using fuzzy logic controller. Lagrangian equation of motion has been used to obtain the appropriate mathematical model of Robotic arms. The results are shown to provide some improvement over those obtained by more conventional means.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2006.04a
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• pp.277-281
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• 2006

A study on stream-groundwater exchange was performed using head and temperature data of stream water, streambed, and groundwater. Groundwater level and temperature were obtained from multi-depth monitoring wells in small-scale watershed. In the summer time, time series of temperatrue data at streambed and groundwater were monitored for three months. In the winter time, we measured the temperature gradient between stream water and streambed. The observed data showed three typical types of temperature characteristics. First, the temperature of streambed was lower than that of stream water; second, the temperature of streambed and stream water was similar; and last, the temperature of streambed was higher than that of stream water. The interconnections between the stream and the streambed were not homogeneously distributed due to weakly developed sediments and heterogeneous bedrock exposed as bed of the stream. The temperature data may be used in formal solutions of the inverse problems to estimate groundwater flow and hydraulic conductivity.

• Journal of the Korean Vacuum Society
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• v.4 no.3
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• pp.327-333
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• 1995

전자소자의 축소화에 따라 박막배선에서의 electromigration은 점차 극소전자 디바이스의 주요 결함원인으로 부각되고 있다. 본 실험에서는 현재 박막 배선 재료로 가장 널리 사용되고 있는 AI-1%Si 금속박막배선의 electromigration에 대한 온도 및 배선길이의 의존성에 관하여 연구하였다. PSG($8000AA$)/SiO2(1000$\AA$)/AI-1%Si(7000$\AA$)/SiO2(5000$\AA$)/p-Si(100)의 보호막처리되지 않은 시편 등을 standard photolithography 공정을 이용하여 각각 제작하였다. 선폭 3$\mu$m, 길이 100, 400, 800, $\1600mu$m등의 AI-1%Si 배막배선구조를 사용하였다. 가속화실험을 위해 인가된 d.c.전류밀도는 4.5X106A/$ extrm{cm}^2$이었고 실온에서 $100^{\circ}C$까지의 분위기 온도에서 electromigration test를 진행하였다. 박막배선의 길에에 따른 MTF(Mean-Time-to-Failure)는 임계길이 이상에서 포화되는 경향을 보이며 이는 보호막층의 유무에 관계없이 나타난다. 선폭 $3\mu$m인 AI-1%Si 박막배선에서 임계길이는, 보호막처리된 시편은 $800\mu$m, 보호막처리되지 않은 시편은 $400\mu$m 배선길이에서 나타난다. 이러한 포화의 경향은 낮은 온도에서 더욱 명확해지는 특성을 보인다. 각 시편에서 electromigration에 대한 활성화에너지도 MTF의 특성과 유사하게 임계길이 이상에서 포화되는 특성을 보인다.

• Applied Microscopy
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• v.22 no.1
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• pp.103-112
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• 1992

Embryonic and postembryonic chicken lenses have been analyzed morphologically to investigate the differentiation of the lens fibers by light and electron microscopes. Morphogenesis of the chick lens was initiated as lens epithelial cells were proliferated and proceeded to elongate the cells characteristically at posterior side, by which the disintegrations of nuclei were accompanied during the early developmental stages. Primary and secondary lens fibers were identified at the late developmental stages, while interconnections between neigh-boring cells well developed and denucleation commenced. On day of hatching, the chicken lens fibers contained few cell organelles within the cytoplasm and showed the homogeneity of cytoplasmic appearance. On day 10 of hatching, the lens were fully differentiated; fiber cells, in which most cell organelles except polysomes were disappeared, showed a slender and elongated prismatic shape. At that stage gap junctions were particularly developed or cytoplasmic ridges are closely interlocked between adjoining cells. In conclusion, differentiation of chick lens involves the division of epithelial cells, the elongation into fiber cells, the loss of cell organelles and the increase of gap junction.