• 한국물환경학회지
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• 제16권4호
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• pp.533-539
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• 2000

A bench-scale reactor using SBR process was experimented with an synthetic wastewater. The main purpose of this investigation was to evaluate applicability in the field and process removal efficiencies in terms of BOD and T-P and its corresponding kinetic parameters. Removal rate of phosphorus was 77% in terms of total phosphorus. Effluent concentrations were $9.8mg/{\ell}$ BOD and $1.1mg/{\ell}$ T-P. Effluent quality was maintained consistently stable by controlling decant volume and operating cycles. The efficiency for phosphorus removal was increased due to decrease in BOD-SS loading value in the range of $0.25{\leq}$aeration time ratio${\leq}0.52$.

• 한국식품조리과학회지
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• 제19권1호
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• pp.11-16
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• 2003

막걸리와 물의 첨가비율에 따른 증편의 기계적, 관능적 품질특성을 0, 1, 2, 3 및 4일간 저장하면서 평가하였다. 증편의 높이와 부피는 1:2 시료가 가장 높아 발효가 잘 된 것으로 나타났고 물성특성의 경우 막걸리와 물의 첨가비율과 저장기간에 의해 시료간에 유의적인 차이를 보여, 물 비율의 증가와 저장기간의 증가에 따라 그 값이 증가하는 경향으로 증편이 단단하게 경화되는 것으로 나타났다. 기계적 색도의 경우 물의 비율기 증가할수록 증편의 명도는 증가하였고 저장기간에 따라 감소하였다. a값, b값은 물의 비율이 증가할수록 감소하였고 저장에 따라 증가하다가 감소하는 것으로 나타났다. 관능적 품질의 경우 관능검사 결과 중편의 막걸리와 물의 첨가비율이 1:2인 시료가 가장 관능적 특성이 큰 것으로 나타났다.

• 상하수도학회지
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• 제18권1호
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• pp.66-72
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• 2004

In this study, quantity and quality of collected rainwater by sand, gravel, soil, lawn and concrete surface, as collection materials were investigated and Rainwater Collection Prediction Model was developed to predict the amount of collected rainwater. The quantity of collected rainwater in concrete surface, gravel, sand, soil and lawn collection system was 1,067L(93.2%), 1,006L(87.8%), 902L(78.8%), 800L(69.9%), 788.5L(68.8%) for 8 months period, respectively. The average turbidity of collected rainwater in concrete surface, gravel, sand, soil and lawn collection system was 3.2NTU, 2.2NTU, 1.9NTU, 1.7NTU, 1.5NTU for 8 months period, respectively. For sand collection material, predicted amount by the Model and actual collected amount were 931.5L and 902L, which were very closed. For gravel collection material, predicted amount by Model and actual collected amount were 1,028.21. and 1,006L, which were very closed. To simulate the optimal rainwater storage volume, the rainfall and evaporation data in Dae-jeon city were used. For sand collection system with 30m2 area, the maximum storage volume was $17m^3$ and 62% of the year was secured for use of 240L/day.

• 한국식품영양학회지
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• 제20권4호
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• pp.399-405
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• 2007

The quality characteristics of breads made by adding levels of 30%, 60%, and 100% aloe gel were investigated. The 60% aloe gel sample had a larger dough volume than the control dough. Also, the loaf volume and specific volume of the bread made with 60% aloe gel were larger than those of the control bread. The pasting temperature increased gradually with the increasing amounts of substituted aloe gel as compared to wheat flour with water added$(66.5{\pm}12^{\circ}C)$; the wheat flour with 100% aloe gel had a pasting temperature of $90.7{\pm}1.1^{\circ}C$. Peak viscosity decreased gradually with increasing amounts of aloe gel when compared to the wheat flour with water added. Setback also was decreased gradually with the increasing amounts of aloe gel as compared to the wheat flour with added water. From the setback decrease it is suggested that the aloe controlled retrogradation of the bread during short-term storage. The crumb color of the bread made with the aloe gel was not significantly different to that of the control bread, and the color of the crumb was yellow-white. Bread hardness decreased gradually with increasing amounts of the substituted aloe gel. However, bread gumminess and chewiness increased gradually with increasing amounts of aloe gel. The springiness of the bread made with 100% aloe gel was lower than that of the control bread. With regard to flavor and taste, the bread made with 100% aloe gel produced a green-like odor and had a bitter taste. The mouth feel of the breads made with aloe gel was considered soft and moist. The overall acceptabilities of the breads made with 30% and 60% aloe gel were not significantly different from the control bread, but the bread made with 100% aloe gel had a green smell and bitter taste. Yet accordingly, the results indicate that functional and health products with improved quality could be developed by adding aloe gel to breads and cakes.

• 산업식품공학
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• 제13권1호
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• pp.50-55
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• 2009

활성 글루텐 첨가가 쌀베이글의 품질 특성에 미치는 영향을 조사하였다. 쌀가루에 글루텐 첨가량이 증가함에 따라 보수력은 증가한 반면, 알칼리수 흡수율은 감소하였다. Pelshenke값과 침전가는 글루텐의 첨가량이 증가함에 따라서 유의적으로 증가는 하였으나 강력분의 Pelshenke값과 침전가에는 미치지 못하였다. 최고점도와 setback 및 peak height와 peak width는 글루텐의 첨가량이 증가함에 따라서 감소하는 경향을 보였다. 글루텐을 23% 첨가할 경우 베이글의 부피는 글루텐 11% 첨가 후와 비교할 때 2배 이상 증가하였으며 글루텐의 첨가량이 증가할수록 베이글의 경도, 검성 및 씹힘성은 감소하는 경향을 나타내었다. 베이글의 비용적과 물 흡수력, Pelshenke값 및 침전가와는 고도의 정의 상관(r =0.962, r =0.964, r =0.966)을 나타내었다.

• 상하수도학회지
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• 제24권6호
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• pp.675-682
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• 2010

Groundwater is an essential drinking water source in Gyungbuk, South Korea. The primary source of nitrate in groundwater is from nitrogen fertilizers. Efficient management of a small drinking water plant requires a good understanding of its status such as the objective and the cognition of users. The objective of this study is to understand user situation and produce useful user-friendly policy based on user cognition. Most people who participated in this study, should take their groundwater from a good quality source. Even though they would like to have a good facility for getting safe water, they were reluctant to do it due to the cost used. It means that people who drink groundwater have no idea that health safety is affected by groundwater quality. The volume used depended upon personal activities such as agriculture and stockbreeding. We can easily find groundwater with nitrate that exceeds drinking water standards. Therefore, we have to carry out groundwater management with two categories ; 1) drinking water only and 2) others according to objectives in small drinking water systems.

• 분석과학
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• 제13권3호
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• pp.399-402
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• 2000

To determine the concentrations of microcystins present in lake water or in tap water using high performance liquid chromatography, it is necessary to concentrate a large volume of water samples (about 20 L) into very small volume (0.1-0.3 mL). Concentration can be conveniently done when disc type solid phase extraction (SPE) apparatus is used. Using this apparatus we have investigated the recovery rates of three kinds of microcystins, RR, YR, LR. The recovery rates were relatively low and the reproducibilities were not good either. It is expected, however, that the appropriate selection of the disc conditioning and eluting solvents and reproducible reconcentration process after SPE will improve both the recovery rates and the reproducibilities.

• 한국식품영양과학회지
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• 제21권5호
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• pp.525-533
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• 1992

쌀을 주원료로 한 재래식 증편에 단백질을 보강하기 위하여 콩단백질(볶은 콩가루, 콩단백추출물)을 첨가한 증편의 최적 가공조건을 구명하고 제품의 전분 및 단백질 품질을 평가 하였다. 쌀가루에 대하여 콩가루 25%(w/w), 설탕 20%(w/w), 막걸리 50%(v/w)로 섞어 $35^{\circ}C$에서 3시간 발효 시켰을 때 부피팽창이 가장 컸으며 설탕을 첨가하지 않으면 거의 발효는 진행 되지 않았고 설탕 첨가량이 많아질수록 반죽이 질어져 성형이 곤란 하였다. 또한 콩가루 대신 soy protein isolate(SPI)를 첨가 하였을 때는 쌀가루에 대하여 SPI 15%, 설탕 20%, 막걸리 60%, 발효시간 2시간, 발효온도 $30^{\circ}C$에서 가장 크게 부풀었다. 발효된 반죽을 수증기로 찌면 발효 부피의 50%정도 부피가 줄어들며 발효시간이 긴것일수록 부피가 크게 줄어 들었다. 부피가 가장 크게 팽창된 조건에서 만든 발효반죽을 15분간 쪄서 제조한 증편의 전분품질(소화율, 환원력) 및 단백질 품질 (소화율, 단백효율비)은 가장 우수 하였으나, 관능검사 및 textrometer에 의한 질감검사의 결과는 콩가루나 SPI첨가 비율이 높을수록 불리하였다. 그러므로 최적 부피 팽창 발효조건과는 달리 관능 및 질감이 좋은 증편은 쌀가루에 대하여 콩가루 20%, SPI 5% 정도의 수준으로 첨가하여 제조 가능할 것으로 생각되었다.

• 한국물환경학회지
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• 제21권6호
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• pp.617-623
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• 2005

Forestry and agricultural land uses constitute 85% of Korea and these land uses are typically mixed in many watersheds. Biological Oxygen Demand (BOD) concentration is a primary factor for managing water qualities of the water resources in Korea. BOD loadings from diffuse sources, however, not well monitored yet. This study aims to assess BOD loadings from diffuse sources and their affecting factors to conserve quality of water resources. Event Mean Concentration (EMC) of BOD was calculated based on the monitoring data of forty rainfall events at four agricultural-forestry watersheds. Exceedence cumulative probability of BOD EMCs were plotted to show agricultural activities in a watershed impacts on the magnitude of EMCs. Prediction equation for each rainfall event was proposed to estimate BOD EMCs: $EMC_{BOD}(mg/L)=EXP(0.413+0.0000001157{\times}$(discharged runoff volume in $m^3$)+0.018${\times}$(ratio of agricultural land use to total watershed area).

• 한국수소및신에너지학회논문집
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• 제27권6호
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• pp.712-720
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• 2016

When bioethanol and water are mixed at a proper ratio, phase separation can occur because of the immiscibility of biobutanol with water. Phase separation in bioethanol blends fuels is a major problem for gasoline vehicle users due to effect of octane number and component corrosion. Thus, in this study, the phase separation of bioethanol was examined effect of bioethanol blends (E3 (3 vo.% bioethanol in gasoline), E5 and E10) in presence of water. The effect were evaluated behavior with phase separation test, simulation test of fuel tank in gas station according to water addition volume and it was investigated change of water content, bioethanol content and octane number for gasoline phase in bioethanol blends (E3, E5 and E10) every 1 week after water addition. The E3 occurred phase separation more easily than the E5 and E10 in small water contents because solubility of water on ethanol content difference in gasoline-ethanol. It was kept a initial level of water content, bioethanol content, and octane number by repeated sample replacing in simulation test of fuel tank.