• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2022년도 학술발표회
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• pp.126-126
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• 2022

Climate change has continued to impact meteorological factors like rainfall in many countries including Nigeria. Thus, altering the rainfall patterns which subsequently affect the crop yield. Maize is an important cereal grown in northern Nigeria, along with sorghum, rice, and millet. Due to the challenge of water scarcity during the dry season, it has become critical to design appropriate strategies for planning, developing, and management of the limited available water resources to increase the maize yield. This study, therefore, determines the quantity of water required to produce maize from planting to harvesting and the impact of drought on maize during different growth stages in the region. Rainfall data from six rain gauge stations for a period of 36 years (1979-2014) was considered for the analysis. The standardized precipitation and evapotranspiration index (SPEI) is used to evaluate the severity of drought. Using the CROPWAT model, the evapotranspiration was calculated using the Penman-Monteith method, while the crop water requirements (CWRs) and irrigation scheduling for the maize crop was also determined. Irrigation was considered for 100% of critical soil moisture loss. At different phases of maize crop growth, the model predicted daily and monthly crop water requirements. The crop water requirement was found to be 319.0 mm and the irrigation requirement was 15.5 mm. The CROPWAT 8.0 model adequately estimated the yield reduction caused by water stress and climatic impacts, which makes this model appropriate for determining the crop water requirements, irrigation planning, and management.

• 한국염색가공학회지
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• 제18권4호
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• pp.20-27
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• 2006

Lyocell is a not only environmentally-friendly but also very advantageous fiber. When Lyocell is soaked in water, its wet tenacity does not decrease and elongation and moisture regain of it are better than cotton. However, one drawback of lyocell is its fibrillation. The fibrills of lyocell were generated during wet process such as scouring and dyeing deteriorates the dyeing color depth and the appearance of fabric. The purpose of this study was to decrease the fibrillation tendency of lyocell fabric using crosslinking agent, epichlorohydrine(ECH). The effects of NaOH scouring and ECH crosslinking were observed. The different types of ECH addition methods to lyocell and the various concentrations of ECH in crosslinking reaction onto dyeing characteristic and fibriallation were investigated. Weight loss and whiteness index of crosslinked lyocell by ECH were examined. K/S values of ECH treated lyocell fabrics dyed with reactive dye were measured and SEM images of untreated and treated lyocells were observed extensively to define the fibrillation tendency. The results were as follows ; 1) ECH treatment showed the effect of weight loss and scouring because ECH crosslinking reaction was conducted in alkaline condition. 2) The increase in ECH concentration from 5 to 30% does not affected K/S value changes. 3) ECH crosslinking can effectively prevent the fibrillation tendency of lyocell.

• 한국농공학회논문집
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• 제58권6호
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• pp.1-8
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• 2016

Crop damages due to agricultural drought has been increased in recent years. In Korea, water resources are limited indicating that proper management plans against agricultural drought are required for better water-use efficiency in agriculture. In this study, irrigation intervals and amounts for various crops and soil physical properties (sandy and silt loams) were estimated using the IWMM model. Five different crops (soybean, radish, potato, barley and maize) at the Bangdong-ri site in Chuncheon were selected to test the IWMM model. IWMM assessed agricultural drought conditions using the soil moisture deficit index (SMDI), and irrigation intervals and amounts were determined based on the degree of agricultural drought (SMDI). Additionally, we tested the effects of surface irrigation and sprinkler irrigation methods and various irrigation intervals of 2, 3, 5 and 7 days. In our findings, the irrigation intervals of 5 and 7 days showed the minimum rrigation amounts than others. When we considered that the intervals of 3 or 5 days are usually preferred to fields, the interval of 5 days was determined in our study. The estimated irrigation amounts for different crops were shown as maize > radish > barley > soybean > potato, respectively. The irrigation amounts for maize and barley were highly affected by soil properties, but other crops have less differences. Also, small differences in irrigation amounts were shown between the surface and sprinkler irrigation methods. These might be due to the lack of consideration of water loss (e.g., evapotranspiration, infiltration, etc.) in IWMM indicating model structural uncertainties. Thus, possible water loss (e.g., evapotranspiration, infiltration) need to be considered in application to fields. Overall, IWMM performed well in determining the irrigation intervals and amounts based on the degree of agricultural drought conditions (SMDI). Thus, the IWMM model can be useful for efficient agricultural water resources management in regions at where available water resources are limited.

• 한국축산식품학회지
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• 제31권6호
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• pp.799-806
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• 2011

This study was conducted to evaluate the effect of the aging period prior to freezing on the meat quality of Hanwoo longissimus dorsi (LD) muscle. Three different combinations of aging and freezing periods (0/90, 20/70, and 40/50) were examined using LD muscle at 24 h postmortem under an identical storage time of 90 d. The pH and lightness slightly increased with increasing aging period. However, there were no significant (p>0.05) differences in redness and yellowness. The solitary freezing treatment (0/90) had the significantly (p<0.05) lowest moisture content. The un-aged treatment had a significantly (p<0.05) higher total loss than the aged treatments due to an increase in thaw drip loss. The aging significantly improved the myofibrillar fragmentation index and shear force of Hanwoo LD muscle (p<0.05). In addition, the aged treatments produced a higher flavor, tenderness, juiciness, and overall acceptability relative to un-aged treatment. However, there was no significant (p>0.05) difference in shear force and sensorial properties between 20 and 40 d aging prior to freezing. Therefore, 20 d aging prior to freezing may be a sufficiently effective strategy to improve the tenderness and sensorial properties of Hanwoo LD muscle.

• 한국축산식품학회지
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• 제43권2호
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• pp.245-268
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• 2023

The effects of phosphate alternatives on meat quality in marinated chicken were investigated with the application of chilling and freezing. Breast muscles were injected with solution of the green weight containing 1.5% NaCl and 2% sodium tripolyphosphate (STPP) or phosphate alternatives. Treatment variables consisted of no phosphate [control (-)], 0.3% sodium tripolyphosphate [control (+)], 0.3% prune juice (PJ), 0.3% oyster shell, 0.3% nano-oyster shell, and 0.3% yeast and lemon extract (YLE) powder. One-third of the meat samples were stored at 4℃ for 1 d, and the rest of the meats were kept at -18℃ for 7 d. In chilled meat, a lower drip loss was noted for control (+) and YLE, whereas higher cooking yield in YLE compared to all tested groups. Compared with control (+), the other treatments except PJ showed higher pH, water holding capacity, moisture content, lower thawing and cooking loss, and shear force. Natural phosphate alternatives except for PJ, improved the CIE L^* compared to control (-), and upregulated total protein solubility. However, phosphate alternatives showed similar or higher oxidative stability and impedance measurement compared to control (+), and an extensive effect on myofibrillar fragmentation index. A limited effect was observed for C^*, h°, and free amino acids in treated meat. Eventually, the texture profile attributes in cooked of phosphate alternatives improved except for PJ. The results indicate the high potential use of natural additives could be promising and effective methods for replacing synthetic phosphate in chilled and frozen chicken with quality enhancement.

• 산업식품공학
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• 제15권3호
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• pp.269-275
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• 2011

야콘 분말의 대체량을 0-30%로 달리하여 스펀지 케이크를 제조한 후 물리화학적 및 관능적 품질특성을 비교하였다. 야콘 분말의 대체비율이 증가함에 따라 반죽의 비중은 단계별로 유의적으로 증가하였고 pH는 감소하는 경향을 나타내었다. 한편 케이크의 비체적과 수분함량은 야콘 분말 대체에 따라 유의적으로 감소하였고 굽기 손실은 증가하였다(p<0.05). 부피지수는 감소하는 경향을 보여 야콘 분말 비율이 높아지면 케이크의 부피 또는 높이가 작아짐을 알 수 있었다. 반면 대칭지수는 야콘 분말 대체량에 따른 유의적인 차이를 나타내지 않았다(p > 0.05). 밝기는 나타내는 L*값은 유의적으로 감소하였으며(p < 0.05), 경도는 점차적으로 증가하였으나 20% 및 30% 대체군 사이에 유의적인 차이는 발견되지 않았다. 소비자 기호도 검사결과 대조군, 10% 및 20% 대체군 사이에 전체적인 기호도에 대한 유의적인 차이는 발견되지 않았으나(p > 0.05), 관능품질을 저해하지 않고 야콘 분말의 건강 기능성 효과 등을 고려할 때 20% 대체군이 가장 적절한 것으로 판단된다.

• 대한화장품학회지
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• 제42권4호
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• pp.367-375
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• 2016

본 연구에서는 락툴로스(lactulose) 51.67%와 갈락토올리고당(galactooligo saccharides) 15.8%로 이루어진 듀올리고(DuOligo)의 섭취를 통하여 피부개선 효능을 조사하였다. 40~60 대의 건강한 여성 37명을 대상으로 대조군(덱스트린)과 실험군(듀올리고군)으로 나누어 각각 8주 동안 섭취 후, 수분보유량, 경표피수 분손실량, 멜라닌지수, 홍반지수와 주름지수를 측정하였다. 그 결과, 듀올리고 섭취 8주 후의 수분 보유량은 대조군에 비하여 수분 보유량이 38.22% 유의적으로 증가하였다(p < 0.01). 대조군의 경피수분손실량은 8주후 $3.39g/h/m^2$로 감소한데 비하여 듀올리고군의 경피수분손실량은 8주후 $5.32g/h/m^2$ 감소하였다. 대조군의 멜라닌 지수는 시간에 따라 그 값이 유의적으로 증가하였으나, 듀올리고군의 멜라닌 지수는 시간에 따른 유의적 차이가 나타나지 않았다. 또한, 듀올리고군은 대조군에 비하여 주름의 총 넓이, 총 주름의 길이, 주름의 수 및 주름의 깊이가 확연하게 감소하였다(p < 0.05). 듀올리고의 피부개선 기능성 소재로서의 응용 가능성을 확인하였다.

• 한국축산식품학회지
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• 제35권6호
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• pp.721-730
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• 2015

The objective of this study was to examine the effect of ginger extract (GE) combined with citric acid on the tenderness of duck breast muscles. Total six marinades were prepared with the combination of citric acid (0 and 0.3 M citric acid) and GE (0, 15, and 30%). Each marinade was sprayed on the surface of duck breasts (15 mL/100 g), and the samples were marinated for 72 h at 4℃. The pH and proteolytic activity of marinades were determined. After 72 h of marination, Warner Bratzler shear force (WBSF), myofibrillar fragmentation index (MFI), pH, cooking loss, moisture content, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and protein solubility were evaluated. There was no significant (p>0.05) difference in moisture content or cooking loss among all samples. However, GE marination resulted in a significant (p<0.05) decrease in WBSF but a significant (p<0.05) increase in pH and MFI. In addition, total protein and myofibrillar protein solubility of GE-marinated duck breast muscles in both WOC (without citric acid) and WC (with citric acid) conditions were significantly (p<0.05) increased compared to non-GE-marinated duck breast muscles. SDS-PAGE showed an increase of protein degradation (MHC and actin) in WC condition compared to WOC condition. There was a marked actin reduction in GE-treated samples in WC. The tenderization effect of GE combined with citric acid may be attributed to various mechanisms such as increased MFI and myofibrillar protein solubility.

• 한국토양비료학회지
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• 제16권4호
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• pp.294-300
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• 1983

토양개량제(土壤改良劑)가 토양구조(土壤構造)의 특성변화(特性變化)에 미치는 영향(影響)을 구명(究明)하기 위하여 친수성(親水性)인 Uresol과 소수성(疎水性)인 Bitumen을 사양토(砂壤土)와 미사질양토(微砂質壤土)에 각각(各各) 처리하여 토양입단(土壤粒團)의 물리적(物理的) 제특성(諸特性)을 분석(分析)한 결과(結果)는 다음과 같다. 1. Bitumen 0.4%, Uresol 0.6% 처리(處理)로 토양구조(土壤構造)의 안정성지수(安定性指數)는 처리(處理)하지 않은 토양(土壤) 0.275~0.416에 비(比)하여 1.650~3.450으로 현저히 증가(增加)되었으며 수중침적용적중(水中沈積容積重)은 크게 감소(減少)되었다. 2. 통기(通氣)-투수성(透水性) 비율(比率)은 사양토(砂壤土)에서 처리(處理)하지 않은 토양(土壤)이 3.8인데 비(比)하여 Uresol처리 토양은 2.2로 감소(減少)되었으며, 미사질양토(微砂質壤土)에서 무처리토양(無處理土壤)이 9.4인데 비(比)하여 Bitumen 처리토양(處理土壤)은 6.9, Uresol처리토양(處理土壤)은 5.3으로 낮았다. 3. 토양구조(土壤構造)의 불안정지수(不安定指數)가 증가(增加)될수록 통기(通氣)-투수성(透水性) 비율(比率)은 급격히 상승(上昇)되다가 지수(指數)가 1 이상(以上)에서는 이 비율(比率)이 매우 완만(緩慢)하게 증가(增加)되었다. 4. 친수성(親水性)인 Uresol처리(處理)는 토양(土壤)의 보수력(保水力)을 2~6% 증가(增加)시켰으나 소수성(疎水性)인 Bitumen 처리(處理)는 보수력(保水力)이 1~3% 감소(減少)되었다.

• 한국농공학회지
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• 제26권4호
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• pp.52-65
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• 1984

In general precise estimation of hourly of daily distribution of the long-term run-off should be very important in a design of source of irrigation. However, there have not been a satisfying method for forecasting of stationar'y long-term run-off in Korea. Solving this problem, this study introduces unit-hydrograph method frequently used in short-term run-off analysis into the long-term run-off analysis, of which model basin was selected to be Sumgin-river catchment area. In the estimation of effective rainfall, conventional method neglects the Soil moisture condition of catchment area, but in this study, the initial discharge (qb) occurred just before rising phase of the hydrograph was selected as the index of a basin soil moisture condition and then introduced as 3rd variable in the analysis of the reationship between cumulative rainfall and cumulative loss of rainfall, which built a new type of separation method of effective rainfall. In next step, in order to normalize significant potential error included in hydrological data, especially in vast catchment area, Snyder's correlation method was applied. A key to solution in this study is multiple correlation method or multiple regressional analysis, which is primarily based on the method of least squres and which is solved by the form of systems of linear equations. And for verification of the change of characteristics of unit hydrograph according to the variation of a various kind of hydrological charateristics (for example, precipitation, tree cover, soil condition, etc),seasonal unit hydrograph models of dry season(autumn, winter), semi-dry season (spring), rainy season (summer) were made respectively. The results obtained in this study were summarized as follows; 1.During the test period of 1966-1971, effective rainfall was estimated for the total 114 run-off hydrograph. From this estimation results, relative error of estimation to the ovservation value was 6%, -which is mush smaller than 12% of the error of conventional method. 2.During the test period, daily distribution of long-term run-off discharge was estimated by the unit hydrograph model. From this estimation results, relative error of estimation by the application of standard unit hydrograph model was 12%. When estimating by each seasonal unit bydrograph model, the relative error was 14% during dry season 10% during semi-dry season and 7% during rainy season, which is much smaller than 37% of conventional method. Summing up the analysis results obtained above, it is convinced that qb-index method of this study for the estimation of effective rainfall be preciser than any other method developed before. Because even recently no method has been developed for the estimation of daily distribution of long-term run-off dicharge, therefore estimation value by unit hydrograph model was only compared with that due to kaziyama method which estimates monthly run-off discharge. However this method due to this study turns out to have high accuracy. If specially mentioned from the results of this study, there is no need to use each seasonal unit hydrograph model separately except the case of semi-dry season. The author hopes to analyze the latter case in future sudies.