• 한국정보통신학회논문지
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• 제15권12호
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• pp.2534-2542
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• 2011

본 논문에서는 CDMA (Code Division Multiple Access) 기반 통신 시스템에서의 가용한 직교 부호의 수보다 많은 수의 사용자 수용을 위해 제안된 하향링크 통계적 다중화 기법인 기존 OCHM (Orthogonal Code Hopping Multiplexing) 기술에 다중 안테나를 사용함으로써 성능이 향상될 수 있음을 보인다. 먼저 직교 부호 할당 방식에 따른 두 가지 다른 OCHM 시스템을 소개하고, 이를 LLR (Log-Likelihood Ratio) 값 계산법에 적용 시 나타내어지는 수식 표현을 유도한다. 다음으로, 유도된 LLR 값에 기반을 두어 터보 부호기를 사용할 때, 언급한 OCHM 시스템의 FER (Frame Error Rate) 성능을 검증한다. 또한 비교를 위해 기존 3GPP 표준에서 사용되는 다중 안테나 심벌 매핑 방식의 성능도 분석한다. 결과적으로, 제안된 직교 부호 할당 방식을 적용한 다중 안테나 기반 OCHM 시스템이 기존 시스템 대비 목표 FER을 만족하는데 있어서 에너지 감소 측면에서 상당한 이득이 있음을 확인한다.

• Ocean and Polar Research
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• 제37권3호
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• pp.189-200
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• 2015

Mesozooplankton biomass including total biomass and size-fractionated biomass and the abundance of major taxonomic groups of copepods were studied in the Northwestern Subtropical Pacific Warm Pool (NSPWP) and the Northern East China Sea (NECS) from 2006 to 2014. Mesozooplankton biomass ranged from 0.69 to $3.08mgC/m^3$ (mean $1.12mgC/m^3$) in the NSPWP and from 10.60 to $69.10mgC/m^3$ (mean $30.33mgC/m^3$) in the NECS with higher values in spring than fall. Percent composition in the biomass of each size group of mesozooplankton varied interannually both in the NSPWP and in the NECS. The smallest size group (0.2~0.5 mm) contributed the least to total biomass in both regions, but significantly higher in the NSPWP than in the NECS. The percent composition in abundance of copepod taxonomic groups (i.e. Calanoida, Cyclopoida, and Poecilostomatoida) also fluctuated interannually. Mean composition of calanoid copepods was higher in the NECS than in the NSPWP, but the opposite pattern was observed for poecilostomatoid copepods. Mesozooplankton biomass both in the NSPWP and in the NECS was negatively correlated with Oceanic $Ni{\tilde{n}}o$ Index (ONI), indicating declines in biomass during El $Ni{\tilde{n}}o$ periods and vice versa during Na $Ni{\tilde{n}}a$ period. The effect of El $Ni{\tilde{n}}o$ on variation of mesozooplankton biomass was more prominent in the NSPWP than in the NECS. These results suggest that mesozooplankton biomass both in the NSPWP and in the NECS responded to El $Ni{\tilde{n}}o$ events, although the biological process that explain the reduced mesozooplankton biomass might be different in both regions.

• 한국토양비료학회지
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• 제44권1호
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• pp.22-28
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• 2011

With the increasing cultivation of acid-loving plants such as blueberries, the artificial acidification of soils is frequently required. This research was conducted to determine the application rates of elemental sulfur (S) required in the soil acidification for blueberry cultivation. Laboratory incubation experiment was conducted to acidify three arable soils (pH 6-7) of different texture to pH 4.5-5.0 by the addition of varying amounts of elemental S. All rates of elemental S addition reduced soil pH, although the efficacy of acidification was related to the application rate and soil characteristics. pH reduction was slow in sandy loam soil, and the final equilibrium pH was obtained after 60, 43, and 30 days of incubation in sandy loam, loam, and silty clay, respectively. Although the final pHs obtained after 93 days of incubation were not significantly different among the three soils, the equilibrium pH was relatively higher in soil of higher clay content in the application rates of 1.5-2.0 g S $kg^{-1}$ soil. The estimated amounts of elemental S required in lowering pH to 4.5-5.0 were 0.59-1.01, 0.67-1.03, and 0.53-0.88 g S $kg^{-1}$ for sandy loam, loam, and silty clay, respectively. The lowest estimated amount of elemental S in the acidification of silty clay soil was attributable to the low organic matter content. For clay soils containing optimum level of organic matter, the application rates of elemental S should be much higher than those values estimated in this research. Soil acidification did not significantly increase the available concentrations of Ca, Mg and K. Extractable Cu and Zn was not greatly affected by the acidification, but extractable Fe, Mn, and Al in the acidified soils were higher than those found in non-acidified soils. Such increases in solubility are attributable to the dissolution of oxides and hydroxides of the elements.

• 한국축산식품학회지
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• 제34권2호
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• pp.192-199
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• 2014

The effects of adding mechanically deboned chicken (MDC) hydrolysates on the quality characteristics of imitation crab stick (ICS) during storage were investigated. ICS was prepared from Alaska Pollack, chicken breast surimi, and protein hydrolysates enzymatically extracted from MDC. ICS samples were divided into 4 groups: without protein hydrolysate (control), added with 0.5% protein hydrolysate (T1), added with 1.0% protein hydrolysate (T2), and added with 1.5% protein hydrolysate (T3). Results showed that crude protein content did not differ significantly among the ICS samples (p>0.05). ICS sample added with MDC hydrolysates had higher crude fat and ash content but lower moisture content than the control (p<0.05). Lightness was significantly lower in T2 and T3 than in the other groups at 0 and 4 wk of storage. Also, whiteness decreased in the groups contained MDC hydrolysates. Breaking force and jelly strength were higher in samples containing MDC hydrolysates compared to control samples (p<0.05). Additionally, saturated fatty acid contents were lower in the groups containing MDC hydrolysates than in control sample groups (p<0.05). Polyunsaturated fatty acid (PUFA) and essential fatty acids (EFA) were significantly higher in T2 and T3 than the control samples. In particular, all samples containing MDC hydrolysates had reduced thiobarbituric acid-reactive substances (TBARS) values at 4 wk. Free radical scavenging activity also was increased with addition of MDC hydrolysates.

• Journal of Advanced Marine Engineering and Technology
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• 제39권1호
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• pp.94-98
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• 2015

최근 정보화 및 컴퓨터 비전 기술의 발전과 함께 객체의 인식 및 추적 기능을 가진 CCTV시스템이 다양한 분야에서 연구되고 있다. 하지만 실외환경에서 발생할 수 있는 그림자의 변화, 조명의 변화, 움직이는 요소들과 같은 배경의 변화는 객체 인지성능에 영향을 주게 된다. 따라서 실외환경에서 배경의 변화를 실시간으로 갱신하기 위해 본 논문에서는 다양한 배경 모델링 기법들을 분석하고, 가중치를 기반으로 한 배경 갱신 알고리즘을 제안한다. 실험을 통해 제안한 알고리즘의 객체 검출 성능은 이전 연구의 객체 검출 성능을 유지하며, 오인식 된 객체 수가 이전 연구에 비해 감소됨을 확인하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제13권9호
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• pp.1272-1277
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• 2000

The present study was conducted to investigate the feasibility of feeding neem kernel meal (NKM) containing diet to growing Japanese quails, which was incorporated into a standard quail diet at 0, 50, 75 or 100 g/kg in place of soyabean meal and deoiled rice bran. Each diet was offered to 30 quail chicks housed in battery cages from day one to five weeks of age. The chicks fed NKM diets gained 123.3, 122.6 and 121.6 g mean body weight, respectively, and which were significantly (p<0.05) lower than that of 129.9 g gained by those of birds fed the control diets. The feed intake and feed conversion ratio of birds in different dietary groups were not significantly altered due to dietary variations. Mean values for retention of dietary energy, N and Ca were found to insignificantly differ (p>0.05) among the treatment groups but P retention was significantly (p<0.01) lower for quails fed 100 g/kg NKM than those in other groups. Blood biochemical constituents, carcass characteristics and organoleptic test for meat also were not found to vary significantly (p>0.05) due to dietary treatments. The histopathology of liver and kidney tissues from NKM fed quails revealed mild degenerative changes. It could be concluded that inclusion of NKM in quail diet reduced the growth besides inducing mild pathological changes in liver and kidney tissues.

• Journal of Nutrition and Health
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• 제41권3호
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• pp.232-241
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• 2008

Moderate alcohol consumption has been known to be associated with reduced risk for coronary heart disease (CHD). We assessed the association between alcohol consumption and CHD-related risk factors [hypertension, diabetes mellitus (DM) , high total cholesterol, high triglyceride (TG), low HDL-cholesterol (HDL-C), and high LDL-cholesterol (LDL-C)] in Korean. After excluding those with extreme intake values, the number of final subjects included in the analysis was 4,662 Korean adults aged over 20 years (1,961 men, 2,701 women) who participate in the 2005 Korean National Health and Nutrition Examination Survey. The subjects were divided into four or five groups; none-alcohol consumption group, moderate alcohol consumption group (<15 or 15.0-29.9 g/d), heavy alcohol consumption group (30-69.9 g/d or ${\geq}$ 70 g/d in men, ${\geq}$ 30 g/d in women). Odds ratios (ORs) were estimated from logistic regression adjusting for potential covariates. Alcohol consumption was inversely associated with low HDL-C in both men and women. However, heavy alcohol intake (${\geq}$ 70 g/d) significantly increased risk for hypertension, DM, and hypertriglyceridemia in men. The frequency of alcohol intake was also associated with CHD risk. The risk for low HDLC was decreased with alcohol consumption (${\geq}$ 1 times/wk), but frequent alcohol intake (${\geq}$ 4 times/wk) increased the risk for hypertension. This study revealed that moderate alcohol consumption has protective effect on CHD-related risk factors in Korean population.

• 자원환경지질
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• 제43권4호
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• pp.343-348
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• 2010

선상 중력 이상값은 기상악화 및 조사 선박의 급작스런 음직임에 의해 많이 왜곡된다. 이러한 자료 왜곡은 잘못된 해석을 유발할 수 있어 필히 제거되어야 하지만 완벽하게 모든 오차를 제거할 수는 없다. 일반적으로 사용하는 교차점 오차 보정은 교차점 자체에 대한 국부적인 보정이기 때문에 교차점 오차 보정을 한 후에도 그 자료에는 많은 오차 값들이 포함되어 있다. 이러한 단점을 해소하기 위하여 교차점에서는 물론이고 모든 자료에 포함되어 있는 오차값들을 최소화하기 위하여 칼만 필터중의 하나인 Rauch-Tung-Striebel(RTS) 필터를 이용하였다. RTS 보정을 수행한결과 자료 변위 폭이 최대 15 mGal에서 2 mGal 미만으로 감소되었고 교차점에서의 오차는 4.21 mGal에서 2.95mGal로 줄어들었다. 이 결과는 RTS 방법이 교차점에서는 물론 모든 자료에 포함되어 있는 오차 값을 최소화 하는데 효율적임을 제시하고 있다.

• 한국식품저장유통학회지
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• 제11권4호
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• pp.522-529
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• 2004

In the grilled fish paste stored at $5^{\circ}C$, the total aerobic bacterial counts were effectively reduced by 2.5 kGy or more. In the samples stored at $30^{\circ}C$, the total aerobic bacterial counts of the samples irradiated at 7.5 kGy were below to the limit of detection (2 log CFU/g). The TBA values of the irradiated samples were considerably higher than those of the controls but not proportional to the irradiation dose. It is apparent that an irradiation treatment causes very little textural degradation and the sensorial quality of the sample was maintained by an irradiation at 7.5 kGy or more.

• Journal of Microbiology and Biotechnology
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• 제22권12호
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• pp.1705-1713
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• 2012

A gene encoding ${\beta}$-glucosidase was cloned from Weissella cibaria 37, an isolate from human feces. Sequence analysis showed that the gene could encode a protein of 415 amino acids in length, and the translated amino acid sequence showed homology (34-31%) with glycosyl hydrolase family 1 ${\beta}$-glucosidases. The gene was overexpressed in E. coli BL21(DE3) using pET26b(+) and a 50 kDa protein was overproduced, which matched well with the calculated size of the enzyme, 49,950.87 Da. Recombinant ${\beta}$-glucosidase was purified by using a his-tag affinity column. The purified ${\beta}$-glucosidase had an optimum pH and a temperature of 5.5 and $45^{\circ}C$, respectively. Among the metal ions (5mM concentration), $Ca^{2+}$ slightly increased the activity (108.2%) whereas $Cu^{2+}$ (46.1%) and $Zn^{2+}$ (56.7%) reduced the activity. Among the enzyme inhibitors (1 mM concentration), SDS was the strongest inhibitor (16.9%), followed by pepstatin A (45.2%). The $K_m$ and $V_{max}$ values of purified enzyme were 4.04 mM and 0.92 ${\mu}mol/min$, respectively, when assayed using pNPG (p-nitrophenyl-${\beta}$-D-glucopyranoside) as the substrate. The enzyme liberated reducing sugars from carboxymethyl cellulose (CMC).