• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.386-386
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• 2012

We studied a bilateral switching device for spin transfer torque (STT-MRAM) based on 3D device simulation. Metal/P/N+or Metal/N/P+ junction device with $30{\times}30nm2$ area which is composed of one side schottky junction at Metal/P/N+ and Metal/N/P+ provides sufficient bidirectional current flow to write data by a drain induced barrier lowering (DIBL). In this work, Junction device confirmed that write current is more than 30 uA at 2 V, It is also has high on-off ratio over 105 under read operation. Junction device has good process feasibility because metal material of junction device could have been replaced by bottom layer of MTJ. Therefore, additional process to fabricate two outer terminals is not need. so, it provides simple fabrication procedures. it is expected that Metal/P/N+ or Metal/N/P+ structure with one side schottky junction will be a promising switch device for beyond 30 nm STT-MRAM.

• ETRI Journal
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• 제38권6호
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• pp.1135-1144
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• 2016

Fractal antenna arrays are geometry-based thinned arrays having multiband applications. The major challenge of these arrays is their large number of elements at higher expansion factors. This article presents the thinning of fractal antenna arrays while maintaining an appropriate balance between the side lobe level and beam width by using various quantized fractal distribution functions. A 2D square fractal antenna array and 3DSierpinski gasket antenna array are considered in this article to validate the proposed distribution functions. Nearly one third of the antenna elements are thinned in each successive iteration except in the case of a one-count distribution function. The proposed technique can simplify practical implementation and exhibits better performance for various parameters such as the side lobe level, side lobe angle, and half power beam width than fully populated fractal antenna arrays.

• 반도체디스플레이기술학회지
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• 제13권3호
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• pp.21-25
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• 2014

The texturing is one of the most important processes for high efficiency crystalline silicon solar cells. The rear side flatness of silicon solar cell is very important for increasing the light reflectance and forming uniform back surface field(BSF) region in manufacturing high efficiency crystalline silicon solar cells. We investigated texturing difference between front and rear side of wafer by texturing of two adhered wafers. As a result, the flatter rear side was obtained by forming less pyramid size compared to the front side and improved reflectance of long wavelength and back surface field(BSF) region were also achieved. Therefore, the texturing of two adhered wafers can be expected to improve the efficiency of silicon solar cells due to increased short circuit current(Isc).

• 대한지리학회지
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• 제43권1호
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• pp.71-86
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• 2008

공간정보를 전달하고 이해하는 과정에서 여러 가지 원인으로 의사소통의 불일치가 발생한다. 이 연구의 목적은 '맞은편' 이라는 공간언어를 통해 공간언어가 갖고 있는 의미의 모호성이 사람들 간 의사소통 문제를 일으키는 하나의 원인이 된다는 점을 실험을 통해서 증명하는 것이다. 단순화된 '사거리'를 활용하는 평가도구를 통해 실험 참가자들이 생각하는 '맞은편'은 어디이며, 그 방향이 맞은편을 얼마나 정확하게 의미하는지를 조사하였다. 본 실험은 대부분의 실험 참가자들이 한 방향 이상을 '맞은편'으로 적절하다고 판단하고 있음을 밝혔다. 이러한 결과는 '맞은편' 이라는 용어가 갖고 있는 의미의 모호성을 증명하는 것이다. 대부분의 실험 참가자들은 준거로 주어진 정사각형 건물의 수직과 수평 방향을 고르게 '맞은편'으로 고려하는 경향을 보였다. 준거가 되는 건물의 형태 변화, 준거가 되는 건물에 내재적 방향성 부여 등도 '맞은편' 의 방향을 결정하는데 의미 있는 영향을 주는 것으로 드러났다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.792-793
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• 2005

Circuit testing process is very important in IC Manufacturing there are two ways in research for circuit testing improvement. These are ATPG Tool Design and Test simulation application. We are interested in how to use parallel technique such as one-side communication, parallel IO and dynamic Process with data partition for circuit testing improvement and we use one-side communication technique in this paper. The parallel ATPG Tool can reduce the test pattern sets of the circuit that is designed in laboratory for make sure that the fault is not occur. After that, we use result for parallel circuit test simulation to find fault between designed circuit and tested circuit. From the experiment, We use less execution time than non-parallel Process. And we can set more parameter for less test size. Previous experiment we can't do it because some parameter will affect much waste time. But in the research, if we use the best ATPG Tool can optimize to least test sets and parallel circuit testing application will not work. Because there are too little test set for circuit testing application. In this paper we use a standard sequential circuit of ISCAS89.

• Journal of information and communication convergence engineering
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• 제11권4호
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• pp.293-297
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• 2013

Delivery of high quality video over a wide area network with large number of users poses great challenges for the video communication system. To ensure video quality, multiple descriptions have recently attracted various attention as a way of encoding and visual information delivery over wireless network. We propose a new efficient multiple description coding (MDC) technique. Quincunx lattice sub-sampling is used for generating multiple descriptions of an image. In this paper, we propose the application of a directional discrete cosine transform (DCT) to a sub-sampled quincunx lattice to create an MDC representation. On the decoder side, the image is decoded from the received side information. If all the descriptions arrive successfully, the image is reconstructed by combining the descriptions. However, if only one side description is received, decoding is executed using an interpolation process. The experimental results show that such the directional DCT can achieve a better coding gain as well as energy packing efficiency than the conventional DCT with re-alignment.

• 전자공학회논문지T
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• 제36T권4호
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• pp.94-102
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• 1999

본 논문은 사전 왜곡기를 이용한 통신 채널 특성의 보상에 관한 것으로서 고려되는 채널 특성으로는 채널에서 발생되는 부가 잡음과 위상 회전 및 주파수 선택성 페이딩이다. 사전 왜곡기는 통신 채널의 전기적 역특성 계수를 송신측에서 계산하여 신호를 미리 왜곡시켜 변조후 전송하므로서 수신측에서는 채널에서 발생되는 장애요인의 영향을 최소화시킬 수 있다. 이를 위해 사전 왜곡기는 적응 등화기의 알고리즘인 TEA(Tricepstrum Equlization Algorithm)을 적용하였으며 이 때 수신측에서는 송신측으로 주기적으로 probing신호를 전송하여야 한다. 이를 기본으로하여 송신측은 통신 채널의 역특성 계수를 얻을 수 있으며 이때 주기적으로 전송되어야 하는 probing 신호의 1주기동안 통신 채널의 특성 변화는 없는 것으로 가정한다. 컴퓨터 시뮬레이션 결과 사전 왜곡기의 성능은 적응 등화기와 같이 양호한 것으로 확인되었으며 이와같은 기법은 향후 이동 통신의 순방향 채널에서 사용할 수 있어 고속 전송을 가능케하는 유용성을 가진다.

• 센서학회지
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• 제22권1호
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• pp.49-53
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• 2013

In this paper, we proposed a laser-based non-contact temperature measuring method for high speed rotating polycarbonate (PC) disk using transparency change of thermocolor. The thermocolor has abilities to change color and transparency due to a change in temperature. The thermocolor is applied on one side of polyvinylidene fluoride (PVDF) membrane. The thermocolor applied membrane is attached to inside of reaction chamber in disk. An optical system consisted of a laser beam radiator and a laser photometer is installed. Laser is irradiated at the bottom side of disk and the transmitted laser beam is detected by the laser photometer at the opposite side of disk. During the disk is rotating, laser is irradiated and detected simultaneously. The laser photometer senses the transmitted laser power and generates voltage as output. The temperature of disk can be detected during the disk is rotating up to 3000 RPM.

• 한국전자통신학회논문지
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• 제11권1호
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• pp.65-72
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• 2016

본 논문에서 풀브리지 컨버터와 2차측은 전류더블러로 구성되어 있는 차량용 양방향 LDC를 개발하였다. LDC는 한쪽의 DC입력을 다른쪽의 DC 출력으로 변환시키는 컨버터이며, 본 논문에서 개발된 컨버터는 양방향으로 전력전달이 가능하다. 개발된 LDC는 1400W에서 90%의 효율을 보이고 2KW에서 약 85%정도의 효율을 나타내는 것이 확인되었다.

• Journal of information and communication convergence engineering
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• 제14권4호
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• pp.222-226
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• 2016

A design method for a compact square loop antenna fed by a microstrip (MS) line for indoor digital television (DTV) applications is proposed. The proposed antenna consists of a square loop, circular sectors, and an MS line. The square loop combined with circular sectors is printed on one side of a substrate, and a $75-{\Omega}$ MS line is printed on the other side. The circular sectors are used as a wideband balun or transition to connect the MS line and the square loop. A prototype of the proposed square loop antenna operating in the DTV band (470-806 MHz) is designed and fabricated on an FR4 substrate. Experimental results show that the proposed antenna has the desired impedance characteristics in the frequency band of 464-1,220 MHz (89.8%) for a voltage standing wave ratio (VSWR) of <2 covering the DTV band, and a broadside gain of 0.8-3.3 dBi in the DTV band.