• 한국연소학회:학술대회논문집
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• 2012.04a
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• pp.21-24
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• 2012

In the iron ore sinter process, temperature distribution pattern in sintering bed is related with productivity and quality of sintered ore. Evenly heat distribution make the uniform quality of sintered ore but in normal operating condition, upper part of bed has lack of heat and scarce quality of sintered ore, thus yeild rate is decreased and productivity is diminished. Therefore, using the additional fuel in the upper part of bed is considered and effect of fuel is discussed. (max. 80 words).

• Journal of Sensor Science and Technology
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• v.14 no.3
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• pp.191-197
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• 2005

When fabricating a vision chip, we should consider the noise problem, such as the fixed pattern noise(FPN) due to the process variation. In this paper, we propose an edge-detection circuit based on biological retina using the offset-free column readout circuit to reduce the FPN occurring in the photo-detector. The offset-free column readout circuit consists of one source follower, one capacitor and five transmission gates. As a result, it is simpler and smaller than a general correlated double sampling(CDS) circuit. A vision chip for edge detection has been designed and fabricated using $0.35\;{\mu}m$ 2-poly 4-metal CMOS technology, and its output characteristics have been investigated.

• Transactions of the Society of Information Storage Systems
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• v.5 no.2
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• pp.89-95
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• 2009

We setup the system to measure the noise characteristics of the 5M complementary metal-oxide semiconductor (CMOS) image sensor by generic measurement indicator of Standard mobile imaging architecture (SMIA) which is one of internal standard of mobile imaging architecture. To evaluate the effect of environment and setting parameters, such as temperature and integration time, we measure the variation of the dark signal, dynamic range and fixed pattern noise of image sensor. We also detect the number of defective pixels and cluster defects defined as adjacent single defect pixels at 5M CMOS image sensor. Then, we find the existence of some cluster defects in experiment, which are not expected in calculation.

• Journal of Welding and Joining
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• v.35 no.2
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• pp.1-5
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• 2017

Many microelectronic devices are miniaturizing the capacitance density and the size of the capacitor. Along with this miniaturization of electronic circuits, tantalum (Ta) capacitors have been on the market due to its large demands worldwide and advantages such as high volumetric efficiency, low temperature coefficient of capacitance, high stability and reliability. During a tantalum capacitor manufacturing process, arc welding has been used to weld base frame and sub frame. This arc welding may have limitations since the downsizing of the weldment depends on the size of welding electrode and the contact time may prevent from improving productivity. Therefore, to solve these problems, this study applies laser spot welding to weld nickel (Ni) and Au-Sn-Ni alloy using CW IR fiber laser with lap joint geometry. All laser parameters are fixed and the only control variable is laser irradiance time. Four different shapes, such as no melting upper workpiece, asymmetric spherical-shaped weldment, symmetric weldment, and, excessive weldment, are observed. This shape may be due to different temperature distribution and flow pattern during the laser spot cutting.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.05a
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• pp.1152-1156
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• 2003

Hard disk drives (HDD) in computer are used extensively as data storage capacity. The trend in the computer industry to produce smaller disk drives rotating at higher speeds requires an improved understanding of fluid motion in the space between disks. PIV measurement was used fer the unsteady flow between the center pair of four disks of four times larger than common radius of HDD disk at several rpm in a fixed cylindrical enclosure. The boundary between inner region and outer region is detected using PIV measurement and the number of dominant vortices s determined clearly. Tip vortices generated by an obstruction with actual-like configuration can be found at inner region. Oscillating flow from the obstruction appears at outer region with complex flow pattern.

• JSTS:Journal of Semiconductor Technology and Science
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• v.2 no.1
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• pp.87-92
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• 2002

We present a simple experimental method for determination of limiting intrinsic fixed-pattern non-uniformity (NU) due to fabrication process in two-dimensional CCD multiplexers (MUXs) that are used for hybrid focal plane arrays. Here, this is done by determining separately the two NUs viz. that are $V_T$ dependent and $V_T$ independent. From these measurements, process dependent NU can be extracted. It is argued that $V_T$ dependent NU can be eliminated by designing novel input circuits whereas $V_T$ independent NU, primarily, dependent on process control and material variations may be reduced but cannot be eliminated completely and hence limits the FPA performance eventually.

• Journal of Ocean Engineering and Technology
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• v.24 no.3
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• pp.11-20
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• 2010

The purpose of this study is the investigation of the wave interaction with the rectangular floating breakwater. The flow profile obtained by PIV technique is represented to understand the vortical flow due to the wave interaction with a rectangular floating breakwater in the roll motion and the fixed condition. Also, the transmission coefficients are compared in both conditions over the extensive wave periods, which represent the performance of breakwater to attenuate the incoming waves. These results would be applied to design the floating breakwater having the mooring system to improve its performance for a certain wave period.

• Proceedings of the IEEK Conference
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• 2002.07c
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• pp.1768-1771
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• 2002

Automatic Transmission System(ATS) was designed to replace the human's manual operation of the gear box. So far, this system operates with the fixed shift pattern information. In this paper, new algorithm considering driver's operation tendency is proposed. Also, to get rid of the uselessly frequent shift of the ATS, the conditions and the status of the vehicle would be included for the evaluation in making a decision of shifting. A field test is done in a car equipped with the computer set connected to Transmission Control Units(TCU) to check the status of the test car, and it shows the excellency of the proposed algorithm.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.11a
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• pp.231-234
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• 2002

This paper considers a system related to biometrics which can control entrance and exit based on pattern and feature of a tooth. It is aimed at research and development of a controling entrance and exit system connected advanced image understanding technique using a tooth recognition that treats a tooth of simple and fixed structure. We think that the system is applied(or utilized) as pre-step or assistance means of face recognition and expect that the system achieves greatly effective results.

• Proceedings of the KIEE Conference
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• 2007.10a
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• pp.429-430
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• 2007

FPA (Focal Plane Arrary)를 이용한 적외선 영상 획득 시스템에서 발생하는 주요 잡음 중 하나는 영상에 존재하는 공간적 고정 패턴 잡음(SFPN, Spatial Fixed Pattern Noise)이다. 이것이 발생하는 주된 요인은 배열을 이루고 있는 각 검출기들과, FPA 출력단에 있는 증폭기의 입출력 응답이 균일하지 않고, 시간이 흐름에 따라 그 응답특성이 변화하기 때문이다. 이 문제를 극복하기 위하여 일반적으로 교정기반 불균일 보정 방법(CBNUC, Calibration Based Nonuniformity Correction)과 장면기반 불균일 보정방법(SBNUC, Scene Based Nonuniformity Correction)이 사용된다. 본 논문은 CBNUC를 사용하는 시스템의 FPA 출력단 회로에 구성된 복수의 증폭기에 존재하는 이득의 차이 및 잡음에 의한 불균일을 보정하기 위한 보간 기법을 제안한다. 실험을 통하여 제안한 기법이 CBNUC 기반 적외선 영상 시스템에서 발생하는 규칙적인 패턴의 SFPN을 효율적으로 제거하는 것을 확인하였다. 또한, 제안한 기법은 CBNUC 기반 적외선 영상 시스템에서 주기적으로 수행해야하는 단일점보정 (OPC, One Point Correction)의 수행횟수를 줄이고, 연산량도 적어 실시간 시스템 구현이 가능하다.