• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제50권3호
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• pp.130-135
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• 2001

In this paper, the distribution characteristics of salt contaminants with the distance from sea in East coast, from Sokcho to Pusan of Korea peninsula were investigated to evaluate the design standard of KEPCO. To get the equivalent salt deposit density(ESDD), conventional brush wiping method was used. As the measuring period is comparatively short, and the measuring interval is long to check the maximum value, acquired ESDD data is very lower than the recommended value in the standard. The measured data didn't follow normal distribution, so it should take the statistical treatment. Through normalizing method, we could get a reliable probability data. In the past investigation, the accumulation characteristics of Japan is consulted to set the criterion, but the climatic condition of Korea is different to Japan. With the comparison of precipitation data and some measured data for long tern accumulation, we could set appropriate accumulation factor.

• ETRI Journal
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• 제37권4호
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• pp.736-742
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• 2015

A serial concatenated decoding algorithm with dynamic threshold is proposed for low-density parity-check codes with short and medium code lengths. The proposed approach uses a dynamic threshold to select a decoding result from belief propagation decoding and order statistic decoding, which improves the performance of the decoder at a negligible cost. Simulation results show that, under a high SNR region, the proposed concatenated decoder performs better than a serial concatenated decoder without threshold with an Eb/N0 gain of above 0.1 dB.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 하계종합학술대회 논문집(1)
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• pp.323-326
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• 2002

In this paper, we study the improved bounds on the performance of low-density parity-check (LDPC) codes over binary-input additive white Gaussian noise (AWGN) channels with belief propagation (BP) decoding in log domain. We define an extended Gallager ensemble based on a new method of constructing parity check matrix and make use of this way to improve upper bound of LDPC codes. At the same time, many simulation results are presented in this paper. These results indicate the extended Gallager ensembles based on Hamming codes have typical minimum distance ratio, which is very close to the asymptotic Gilbert Varshamov bound and the superior performance which is better than the original Gallager ensembles.

• 전기의세계
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• 제28권9호
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• pp.43-50
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• 1979

Silicon nitride films were chemically deposited on silicon substrates by reacting SiCl$_{4}$ and NH$_{3}$ in a nitrogen atmosphere at 700~1100 .deg.C. The deposition rate increased rapidly with deposition temperature upto about 1000 .deg.C, and became less temperature dependent above this temperature. The etch rate of films in buffered HF solution decreased, with an increase of deposition temperature, and a heat treatment at a temperature higher than that of the deposition considerably reduced the etch rate. It indicates that the heat treatment resulted in a densification of the films. Surface charge density of 3~4 * 10$^{11}$ /cm$^{2}$ was determined from the C-V characteristics of MNS diode, and it was also found that surface charge density depended on deposition temperature, but not film thickness. The current-voltage characteristics displayed a logI-V$^{1}$2/ dependence in the temperature range of 300~500.deg.K. Measurement of the slope of this characteristics and its dependence on temperature and bias polarity suggest that conduction in sili con nitride films arises from the Poole-Frenkel mechanism.

• 한국균학회지
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• 제7권2호
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• pp.91-116
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• 1979

본(本) 연구(硏究)는 예산지역(禮山地域)(A)과 광산지역(光山地域)(B)의 왕대나무(Phyllostachys reticulata)의 현존량(現存量)과 그 토양(土壤) 미세균류상(微細菌類相)을 조사(調査)한 것이다. 왕대나무의 죽림밀도(竹林密度)는 예산지역(禮山地域)이 17,250본(本)/ha이며 광산지역(光山地域)이 14,780본(本)/ha으로서 예산지역(禮山地域)이 16.1%가 많았다. 양지역(兩地域)의 환경요인(環境要因)은 B지역(地域)의 생장기간(生長期間)의 평균기온(平均氣溫)이 A지역(地域)보다 $1.5{\sim}2^{\circ}C$가 높았고 토양온도(土壤溫度)도 $1{\sim}2^{\circ}C$가 높았으며 토양내(土壤內)에 함유(含有)되어 있는 전실소(全室素), 인산(燐酸) 및 유기물질량(有機物質量)도 약간(若干)많았다. 또 B지역(地域)에서는 낙엽량(落葉量)과 부식량(腐植量) 그리고 죽림내(竹林內)의 식생수량(植生數量)도 많았으며 죽림지(竹林地)에서 환원(還元)되는 각종(各種) 유기물(有機物) 분해(分解)에 관여(關與)하는 미세균류(微細菌類)도 Mortierella elongata, Mucor circinelloides, Aspergillus japonicus, Penicillium waksmani and Trichoderma lignorum등의 5종(種)이 더 많았다. 온도(溫度)는 죽림내부(竹林內部)로 들어 갈수록 낮았고 습도(濕度)는 높았다. 죽림내(竹林內)의 상대조도(相對照度)의 비율(比率)은 A지역(地域)이 4.19% B지역(地域)이 2.7%로서 하단분(下端部)에서는 모두 광합성작용(光合成作用)을 할 수 있는 능력(能力)이 상실(喪失)되었으나 조도(照度)가 약(弱)할수록 표토(表土)근처에서 서식(棲息)하는 미세균류(微細菌類)는 오히려 활동력(活動力)을 강(强)하게 하는 것으로 생각한다. 생산구조도(生産構造圖)에서 B지역(地域)의 광합성부(光合成部)의 최대량(最大量)이 대나무 지상부(地上部)의 상단(上端)에 위치(位置)하고 있어서 높은 생산량(生産量)을 유지(維持)하는데 효과적(效果約)인 구조(構造)였다고 생각된다. A,B지역(地域) 죽림(竹林)에서 $D^2H$, $w_s,\;w_b$, 및 $w_l$ 상대생장식(相對生長式)을 유도(誘導)한 결과(結果)는 다음과 같다. A지역(地域) $logw_s=0.5262\;logD^2H+1.9546$ $logw_b=0.6288\;logD^2H+1.5723$ $logw_l=0.5181\;logD^2H+1.8732$ B지역(地域) $logw_s=0.5433\;logD^2H+1.8610$ $logw_b=0.1630\;logD^2H+2.3475$ $logw_l=0.4509\;logD^2H+2.0041$ 상기(上記)한 식(式)을 적용(適用)하여 10a당 현존량(現存量)을 조사(調査)한 결과(結果) A지역(地域) $w_s=1128.83kg,\;w_b=689.05kg,\;w_l=926.69kg$ 으로 $w_e=2744.57kg$이었고, B지역(地域) $w_s=1206.66kg,\;w_b=679.92kg,\;w_l=1112.51kg$으로 $w_t=2999kg$이였다. 따라서 A,B양지역간(兩地域間)에 있어서 $D^2H,\;w_s,\;w_b$, 및 $w_l$의 현존량(現存量)을 비교한 결과(結果)(t-test), $D^2H,\;w_s,\;w_b,\;w_l$에서는 유의차(有意差)가 인정되었으나 $w_b$는 유의차(有意差)가 없었다. 토양생(土壤生) 미세균류(微細菌類)를 조사(調査)한 결과(結果) 158균주(菌株)를 분리(分離)하고 55종(種)을 동정(同定)하였다. 그 중 A지역(地域) 50종(種), B지역(地域) 55종(種)으로 양지역(兩地域)의 우점종(優占種)들은 다음과 같다. Trichoderma viride, Penicillium janthinellum, P. commune, Aspergillus oryzae, A. niger, A. gigantus, A. fumigatus, Mortierella ramaniana, var. anguliFPora, Mucor hiemalis와 Zygorhynchus moelleri. 이상(以上)의 결과(結果)에 의(依)하면 토성(土性)이 좋고 토양양료(土壤養料) 및 토양생(土壤生) 미세균류(微細菌類)의 증가(增加) 그리고 생육기간(生育期間)의 온도(溫度)가 왕대나무의 생장(生長)이나 임상식물(林床植物)의 종(種)과 양(量)을 증가(增加)시킨 것으로 나타났고 왕대나무의 현존량(現存量)과 환경요인(環境要因)과의 상관관계(相關關係)는 이들의 모든 요인(要因)이 상호연관(相互連關)을 갖고 복잡(複雜)하게 작용(作用)한 것으로 보며 더욱 죽림밀도(竹林密度)가 중용(重要)한 인자(因子)로 작용(作用)한 것같다.

• Nutrition Research and Practice
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• 제5권2호
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• pp.150-156
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• 2011

Few studies have shown the correlation between metabolic syndrome and bone mineral density (BMD). The main pathogenic mechanisms of metabolic syndrome rely on chronic low-level inflammatory status and oxidative stress. There are few studies that examine the gender-specific effects of inflammation and antioxidants on BMD. In this study, we evaluated the relative contribution of these factors in patients with metabolic syndrome. We conducted a cross-sectional study of 67 men and 46 postmenopausal women with metabolic syndrome; metabolic syndrome was defined as having three or more metabolic syndrome risk factors. BMD, body fat mass, and lean body mass were evaluated. We also examined the levels of high sensitive C-reactive protein (hs-CRP), interleukin-6 (IL-6), adiponectin, vitamin E, and C in serum. Log-transformed hs-CRP levels were significantly higher in lumbar spine osteoporotic subjects than in normal subjects for women but not for men. There was no significant difference between the normal group and the osteoporotic group in other inflammatory markers. Stepwise regression analyses for BMD of the lumbar spine showed that lean body mass and vitamin E were significant determinants in men. Lean body mass and log-transformed hs-CRP were significant determinants in women Analysis for BMD of the femoral neck showed that lean body mass was a significant determinant for both men and women. There was no significant factor among the inflammatory markers or antioxidant vitamins affecting the femoral neck BMD for either gender. In conclusion, while hs-CRP is an independent predictor of the BMD of the lumbar spine in women, vitamin E showed profound effects on BMD in men but not women with metabolic syndrome.

• The Plant Pathology Journal
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• 제16권6호
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• pp.312-317
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• 2000

The selected five plant growth-promoting rhizobacteria (PGPR) strains, WR8-3 (Pseudomonas fluorescens), WR8-6 (P. putida), WR9-9 (P. fluorescens), WR9-11 (Pseudomonas sp.), and WR9-16 (P. putida) isolated in the rhizosphere of watermelon plants were tested on their growth promotion and control effect against gummy stem rot of watermelon. Strains, WR8-3 and WR9-16 significantly increased stem length of watermelon, and there was a little increase in leaf area, fresh weight and root length when strains, WR8-3, WR9-9 and WR9-16 were treated. Generally, seed treatment was better for plant growth promotion than the soil drench, but there was no significant difference. Seed treatment and soil drench of each bacterial strain also significantly reduced the mean lesion area (MLA) by gummy stem rot, but there was no significant difference between the two treatments. At initial inoculum densities of each strain ranging from 10$^6\;to\;10^{15}$ cfu/g seed, approximately the same level of disease resistance was induced. But resistance induction was not induced at the initial inoculum density of 10$^3$ cfu/g seed. Resistance was induced by treating the strains, WR9-9, WR9-11 and WR9-16, on all of four watermelon varieties tested, and there was no significant difference in the decrease of gummy stem rot among varieties. Populations of the strains treated initially at log 9-10 cfu/g seed, followed with a rapid decrease from planting day to 1 week after planting, but the population density was maintained above log 5.0 cfu/g soil until 4 weeks after planting. Generally no or very weak in vitro antagonism was observed at the strains treated excepting WR9-11. Rifampicin-resistant bacteria which had been inoculated were not detected in the stems or leaves, which suggesting that the bacterium and the pathogens remained spatially separated during the experiment. This is the first report of rsistance induction in watermelon to gummy stem rot by PGPR strains.

• Corrosion Science and Technology
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• 제3권4호
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• pp.131-139
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• 2004

Effects of PbO on the repassivation kinetics and characteristics of passive film of Alloy 690 were examined to elucidate the influences of PbO on the SCC resistance of that alloy. The repassivation kinetics of the alloy was analyzed in terms of the current density flowing from the scratch, i(t), as a function of the charge density that has flowed from the scratch, q(t). Repassivation on the scratched surface of the alloy occurred in two kinetically different processes; passive film initially nucleated and grew according to the place exchange model in which log i(t) is linearly proportional to q(t), and then grew according to the high field ion conduction model in which log i(t) is linearly proportional to 1/q(t) with a slope of cBV. The cBV is found to be a parameter representing repassivation rate and hence SCC susceptibility of the alloy. The lower the value of cBV, the faster the repassivation rate and the higher the SCC resistance of an alloy. Addition of PbO to pH 4 and 10 solutions increased the value of cBV of alloy 690, reflecting slower repassivation rate than without PbO. The change in the value of cBV was grater in pH 10 than in pH 4. The increase in SCC susceptibility of alloy 690 with the addition of PbO to solution was presumably due to the Cr-depletion in the outer parts of passive film of the alloy with an incorporation of Pb compounds in the film, which was revealed by Mott-Schottky, AES and XPS analyses.

• 식품보건융합연구
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• 제4권4호
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• pp.1-9
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• 2018

To determine the effect of Vitex doniana (leaves stem and root bark) ethanolic extracts on lipid profiles of Poloxamer 407 (P407) induced hyperlipidemic and normal rats. Fifty four mixed sex rats weighing 100-200g were divided into nine groups comprising six animals per group. At the end of the 21 day, the animals were sacrificed and blood sample were collected for determination of serum levels of: Total cholesterol (TC), Triacylglycerides (TAG), High-density lipoprotein cholesterol (HDL-c) and Low-density lipoprotein cholesterol (LDL-c). The studies showed that all induced treated groups significantly (P<0.05) lower serum levels of TC, TAG, LDL-c and significantly (P<0.05) increased HDL-c when compared to the P407 induced hyperlipidemic control. The normal treated groups showed no significant (P>0.05) difference in the serum levels of TC, TAG, LDL and HDL when compared to the normal control group. Calculation of atherogenic risk predictor indices of the induced treated groups showed that all the extracts significantly (P<0.05) lowered the LDL-c/HDL-c, log (TAG/HDL-c) and significantly (P<0.05) increased HDL-c/TC ratio when compared to the P407 induced hyperlipidemic control group. The atherogenic risk predictor indices of normal treated groups showed no significant difference (P>0.05) in LDL-c/HDL-c, Log (TAG/HDL-c) and HDL-c/TC ratio when compared to the normal control group. The study demonstrates the phytotherapeutic effect of Vitex doniana (leaves, stem and root bark) ethanolic extract in poloxamer 407 induced hyperlipidemia.

• 한국정보통신학회논문지
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• 제12권9호
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• pp.1654-1665
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• 2008

본 논문에서는 대표적인 반복 부호 알고리즘인 터보 부호, LDPC부호 TPC 등 세 가지 알고리즘에 대해 8PSK 이상의 다치 변조 방식 적용을 위해 수신단에서 비트 분리 방법을 제시한다. 수신된 I, Q 심볼만을 이용하여 세 비트 이상의 비트를 분리하기 위한 LLR 방식에 기초를 하여 LLR 방식의 단점인 복잡도를 개선하기 위해 Euclidean, MAX, sector, center focusing 방식에 대해 검토하였으며, 세 가지 반복 부호에 대해 최적의 비트 분리 방법을 제시하였다. 또한 DVB-S2에 적용되는 double ring 구조의 16-APSK, 지상파 DMB에 적용되는 격자구조의 16-QAM 방식에 대해 최적의 비트 분리 방법을 제시하였다.