• Electrical & Electronic Materials
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• v.9 no.3
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• pp.277-283
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• 1996

The temperature dependent characteristics of hydrogenerated amorphous silcon thin film transistor (a-Si:H TFT) with a bottom gate of N-Type <100> Si wafer were investigated. Drain current on the hysteresis characteristic curve showed an exponential variation. Hysteresis area of TFT increased with the gate voltage increased and decreased with the small gate voltage. According to the variation of gate voltages, drain current of TFT increased by temperature increase, and hysteresis characteristics mainly depended on the temperature increase. The hysteresis current showed negative characteristics curve over 383K. The hysteresis occurance area and the differences of forward and reverse sweep were increased at the higher temperature. Hysteresis current of I$_{d}$(on/off) ratio decreased at the lower temperature and increased at the higher temperature.e.

• Transactions of Materials Processing
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• v.27 no.2
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• pp.100-106
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• 2018

In the continuous casting process, the incidence of transverse surface cracks on the piece may occur by multiple and diverse variables. It is noted that mathematical models may predict only the occurance of the transverse surface cracks, but can require a lot of time (more than three days) to produce a result with this process. This study applied neural networks to predict whether the cracks on the piece surface occurs or does not occur. The computation time was shortened to three minutes, making it applicable to an on-line program, which predicts the non-cracks or cracks of the piece surface in the actual continuous casting process. In addition, the operating conditions to prevent the occurrence of the transverse surface cracks, using decision boundaries were also suggested.

• Journal of Sericultural and Entomological Science
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• v.30 no.2
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• pp.84-87
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• 1988

Tow Soil fumigants, cylon and chloropiclin were examined for mulberry graftage growth on the nursery garden. Thirty ml/$m^2$ of each fumigants was injected and followed vinyl coverage 4 weeks before planting. Fumigants increased clearly diameter and branch length of graftages, and controled weeds occurance. These effects showed a little bit higher in chloropiclin than in cylon, but no difference statistically at 5% LSD.

• Journal of the Korean Institute of Telematics and Electronics
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• v.26 no.11
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• pp.1743-1751
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• 1989

In this paper, we consider trellis-coding techniques with the convolutional encoder R=k/(k+1) for improving the reliability of digital transimission over bandlimited noisy PRS and 49-QPRS channels. Employing the R=k/(k+1) convolutional code for the PRS channel results in over 3 dB of coding gain comparing with the baseline system. The trellis-coded 49-QPRS system can be realized by combining the 9-QPRS system with the R=1/2 convolutiona code, which can be improved by over 2dB coding gain comparing with the 9-QPRS system. In additin, we study a method of avoiding the occurance of unlimited runs of identical output to prevent operation of timing error.

• The korean journal of orthodontics
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• v.17 no.1
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• pp.85-91
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• 1987

The aim of this study was to clarify whether bonding/debonding procedure will affect the occurance of enamel crack. The frequency of enamel crack was compared between before-bonding and after-debonding on 200 human extracted teeth. Each facial surface of the tooth was divided in 9 fragments. A presence of crack, which was classified by its direction as vertical, horizontal and oblique crack, was surveyed in each fragment. Number of all cracks in facial surface was 1355 at before-bonding, and 1605 at after-debonding, so it revealed significant increase rate of $18.5\%$, but compared by fragment, cracks were significantly Increased in OC, OD, CC and GC fragments. All kinds of cracks were significantly increased, especially increase rate of oblique crack reached $54.9\%$. The increase rate of cracks was not superior at any fragment or region, but some evidence was seen in CC fragment. Judging from the above, increase of crack is unavoidable with bonding/debonding procedures.

• Journal of agricultural medicine and community health
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• v.3 no.1
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• pp.27-34
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• 1978

For the purpose of prevention and improvement of Korean rural women's anemia, the author has performed a study on the factors related to host and environment in order to acquire the basic data for public health activities from July, 1978 to September, 1978. The summarized results were as follows. 1. The prevalence of anemia was found in 38.6%, and the mean hemoglobin, hematocrit and specific gravity level were $12.25{\pm}1$. 79g/dl, $36.1{\pm}5.35%$, $1.053{\pm}0.004$ each other. 2. It was recognized and had statistically significance that the occurance of anemia was markedly influenced by 3 items; family size, yearly income per household and intensity of labor.

• Journal of the Korean Magnetics Society
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• v.4 no.2
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• pp.130-134
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• 1994

This paper describes the occurance of bumps in playback spectrum while reading with MIG heads. The amplitudes of the bumps in theoretically predicted frequencies are investigated by computer simulation. Three cases of MIG head structure are simulated, one without pseudo gaps, the other two with pseudo gap thicknesses of $0.02\;\mu\textrm{m}\;and\;0.2\;\mu\textrm{m}$ on both sides of the main gap, respectively. It is assumed that metal powder tapes are used. The results show that the bumps occur at predicted frequencies and the amplitudes of the bumps agree well with predicted values.

• Journal of Society of Preventive Korean Medicine
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• v.4 no.1
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• pp.152-162
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• 2000

The present condition of study on the wave-resonance for the bio-KI is observed. The results are as follows: 1. Tn the wave-resonant stand point, the tendency of studying on KI is showed in the several field all over the world. 2. Because it is originated radionics, the wave-resonant tools of MRA insistenting minute-magnetism-resonance-apparatus need the more severe data in the side of electric circuit. 3. The wave resonance apparatus according to the frequency occurance transmits low-frequency's vibration ratio to the electric stimulating aspect. 4. The wave-water is considered on the application of wave-resonance transcription on the water, and needs the comprehension of torsion-field level.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.8-13
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• 1997

In order to utilize the information of well-known grinding data or grinding machine, a database needs to be designed by considering the delicate property of the machine tools for the high precision and quality of the demanding specification. Among the machine tools, machining conditions of the grinding are various and knowledge repeatance obtained form the grinding process are less credable.Therefore it is desirable for D/B, which is used to set the grinding conditions, to utilize the maximum machine tool capability. The present paper studied occurance limit of chatter vibration and burn considering the characteristics of machine tool. And also basic experiments were performed to establish optimum grinding canditions which can maximize the machining efficiency.

• Korean journal of applied entomology
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• v.28 no.4
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• pp.246-253
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• 1989

새로운 문제해충을 찾아내려면 작물별로 전국적인 survey가 이루어져야 한다. 인력과 경비면 그리고 수행상의 어려움이 있으므로 경작자나 그 지역의 농촌지도소를 통하여 문의.의뢰된 해충들을 살펴보면 그 해의 대체적인 해충발생상황을 알아볼 수 있다고 생각된다. 농업기술연구소 곤충과에는 1988년 40건의 민원과 의뢰사항이 접수.처리되었다(표 1). 그중 해충동정 및 방제법에 대한 것이 31건, 현지발생행동조사 의뢰 3건, 해충관계자료에 대한 문의가 3건 등이었다. 접수된 민원중에서 일부를 제외하고 각 해충의 발생상황을 작물별로 기술하여 기록을 남김으로서 금후 연구를 의한 기초 자료로 제공코자한다.