• JSTS:Journal of Semiconductor Technology and Science
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• v.12 no.4
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• pp.388-396
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• 2012

In this paper, a $320{\times}240$ pixel, 80 frame/s CMOS image sensor with a low power dual correlated double sampling (CDS) scheme is presented. A novel 8-bit hold-and-go counter in each column is proposed to obtain 10-bit resolution. Furthermore, dual CDS and a configurable counter scheme are also discussed to realize efficient power reduction. With these techniques, the digital counter consumes at least 43% and at most 61% less power compared with the column-counters type, and the frame rate is approximately 40% faster than the double memory type due to a partial pipeline structure without additional memories. The prototype sensor was fabricated in a Samsung $0.13{\mu}m$ 1P4M CMOS process and used a 4T APS with a pixel pitch of $2.25{\mu}m$. The measured column fixed pattern noise (FPN) is 0.10 LSB.

• Proceedings of the KIPE Conference
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• 2001.10a
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• pp.286-290
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• 2001

This paper describes an improved short-circuit protection method with a boost type rectifier using a multilevel ac/dc power converter. The output dc power of the proposed converter can be disconnected from the load within several hundred microseconds at the instant of short-circuit fault. Once the fault has been cleared the dc power is reapplied to the load. The rising time of the dc load voltage is as small as several hundred microseconds, and there is no overshoot of the dc voltage because the dc output capacitors hold undischarged state. The converter, which employs the proposed method, has the characteristics of a simplified structure, reduced cost, weight, and volume compared with a conventional power supply, which has frequent output short-circuits. Experimental results are presented to verify the usefulness of the proposed converter.

• Journal of the Korean Society of Costume
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• v.56 no.7 s.106
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• pp.17-30
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• 2006

The objectives of this study are to research into the traditional costume succession in south and north korea, and to compare similarity and difference of kinds, names, drawing of Jegory. Conclusions are described as follows: 1. In sort of Jegory, south and north korea have same kind of Jegory according to traditional form. But in making method, south korea have pursued various style from traditional type to modern type, north korea have maintained just simple and practical basic style. 2. South and north korea have used same or similar names for the basic part of Jegory. But north korea has made new names for constructional needs, so many differences were shown in the name of details. 3. In drawing of Jegory, north korea has hold traditional method and then tried to seek for rational, scientific technique. Also, due to the influence of south korea that advanced in modern aesthetic, drawing of Jegory in north korea were changed to similar.

• Journal of Applied Reliability
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• v.10 no.1
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• pp.65-71
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• 2010

NAND-type SONOS with a separated double-gate FinFET structure (SDF-Fin SONOS) flash memory devices are proposed to reduce the unit cell size of the memory device and increase the memory density in comparison with conventional non volatile memory devices. The proposed memory device consists of a pair of control gates separated along the direction of the Fin width. There are two unique alternative technologies in this study. One is a channel doping method and the other is an oxide thickness variation method, which are used to operate the SDF-Fin SONOS memory device as two-bit. The fabrication processes and the device characteristics are simulated by using technology comuter-adided(TCAD). The simulation results indicate that the charge trap probability depends on the different channel doping concentration and the tunneling oxide thickness. The proposed SDG-Fin SONOS memory devices hold promise for potential application.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.694-697
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• 2003

In applying LCD to TV application, one of the most significant factors to be improved is image sticking on the moving picture. LCD is different from CRT in the sense that it's continuous passive device, which holds images in entire frame period, while impulse type device generate image in very short time. To reduce image sticking problem related to hold type display mode, we made an experiment to drive LCD like CRT. We made articulate images by turn on-off backlight, and we realized the ratio of Back Light on-off time by adjusting between on time and off time for video signal input during 1 frame (16.7ms). Conventional CCFL (cold cathode fluorescent lamp) cannot follow fast on-off speed, so we evaluated new fluorescent substances of light source to improve residual light characteristic of CCFL. We realized articulate image generation similar to CRT by blinking drive. As a result, reduced image sticking phenomenon was validated by naked eye and response time measurement.

• International Journal of Concrete Structures and Materials
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• v.2 no.2
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• pp.107-113
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• 2008

The last 10 years have seen considerable growth in the use of proprietary and special repair cements for concrete pavements in the state of Oklahoma. Many of these products lend themselves to "fast track" construction techniques that allow reopening to traffic within 12 hours or less. These products achieve high early strengths by accelerating the Portland cement hydration process for both Type I and Type III cements. In this paper, the important features of a durable repair which include strength, compatibility and bond or adhesion are first discussed. Then the development, testing and field implementation of the aforementioned materials are discussed including the learning curve required to implement a repair system, not just install a new material. Some of the materials discussed, while expensive on a cost per unit basis, hold great promise for economical use on fast track project.

• Journal of Welding and Joining
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• v.23 no.2
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• pp.75-80
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• 2005

The effect of chemical constituents of $(Cr,\;Fe)_7C_3$ carbide phase on its hardness in the chromium-carbide type Cr white iron hardfacing weld deposits has been investigated. In order to examine $(Cr,\;Fe)_7C_3$ carbide phase, a series of filler metals with varying chromium contents was used. The alloys were deposited once or twice on a mild steel plate using the self?shielding flux cored arc welding process. The hardness of $(Cr,\;Fe)_7C_3$ carbide phase was measured by the micro-Vickers hardness test. It was shown that hardness of $(Cr,\;Fe)_7C_3$ carbide phase increased with increasing Cr content in $(Cr,\;Fe)_7C_3$ carbide phase. This behavior of the hardness of $(Cr,\;Fe)_7C_3$ carbide phase was explained by the types of chemical bonds that hold atoms together in $(Cr,\;Fe)_7C_3$ carbide phase.

• Journal of the Korean Society for Heat Treatment
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• v.10 no.4
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• pp.232-236
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• 1997

A rectangular type circulating fluidized bed (CFB) with an internal nozzle and two partition walls was proposed. In this modified CFB, an internal nozzle and two slanted partition walls were additionally set in the riser. This cold mode apparatus was made of acrylic resin; the riser was 1500mm high and $1000{\times}1000mm^2$ in the cross sectional area, the internal nozzle was 200mm high and 10mm in the inner diameter, and the partition wall was 7mm thick. Glass beads of $91{\mu}m$ in the mean diameter were employed as bed materials. In the cold mode by using the proposed CFB with an internal nozzle, it was possible to change the particle hold up by changing the gas flow ratio of the nozzle to the total(Qn/Qt). It was found that the inflection point which devided the bed structure between the dense and the dilute phase in the riser varied with Qn/Qt.

• Journal of Astronomy and Space Sciences
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• v.29 no.2
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• pp.163-167
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• 2012

Although the identification of the progenitors of type Ia supernovae (SNeIa) remains controversial, it is generally accepted that they originate from binary star systems in which at least one component is a carbon-oxygen white dwarf (WD); those systems are grouped under the wide umbrella of cataclysmic variables. Current theories for SNeIa progenitors hold that, either via Roche lobe overflow of the companion or via a wind, the WD accumulates hydrogen or helium rich material which is then burned to C and O onto the WD's surface. However, the specifics of this scenario are far from being understood or defined, allowing for a wealth of theories fighting for attention and a dearth of observations to support them. I discuss the latest attempts to identify and study those controversial SNeIa progenitors. I also introduce the most promising progenitor in hand and I present observational diagnostics that can reveal more members of the category.

• Transactions of the Korean Society of Mechanical Engineers
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• v.12 no.6
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• pp.1320-1326
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• 1988

This paper deals with the behavior of surface crack growth and the characteristics of surface micro-crack distribution under creep and creep-fatigue with 1 min. and 10 min. of load holding times at 593.deg.C, in air. The test specimen is a plate type with a small artificial defect of type 304 the small defect has been carried out by the surface replica method and optical microphotography. The experimental results have been interpreted from the view-point of fracture mechanics. It can be concluded that the longer the hold time the longer the total life time. Most of surface micro-cracks initiate at grain boundaries before the specimen reaches 20% of its total life time, a few of them lead to fracture by coalescence with the main crack.