• Magazine of the Korean Society of Agricultural Engineers
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• v.44 no.3
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• pp.136-145
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• 2002

Monitoring data from agricultural reservoirs throughout the country were analyzed to evaluate the limiting factor fur algal growth and relationships between Chl-a, total phosphorus (TP), and total nitrogen (TN). Total 394 reservoirs ranging from below 500 ㎥ to over 50 million ㎥ in storage volume were monitored from 1990 to 2000 with respect to TP, W, Chl-a, and their annual mean values were used fur the analysis. Based on N/P ratio, the dominant limiting factor for algal growth was turned out to be phosphorus in agricultural reservoirs (about 83%). Therefore, the proper managements of phosphorus in the agricultural watershed appear to be crucial to prevent excessive on algal growth. The effects of phosphorus and nitrogen ware most eminent during the summer period. And the effect of nutrients on the algal biomass (Chl-a) development appeared to be greater in smaller the reservoirs than in larger ones. Generally, Chl-a and TP demonstrated a close relationship while that of Chl-a and TN showed less correlationship. Chl-a and chemical oxygen demand (COD) also showed a good relationship. Beth ratios of Chl-a / TP and Chl-a / COD relationships were within the range of literature values. Quantitative analysis of TP and COD is relatively convenient compared to that of Chl-a, and the relationship between TP and COD and Chl-a from this study could be used beneficially for water quality management of agricultural reservoirs and related water quality modeling.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.9
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• pp.1338-1343
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• 2016

The purpose of this study was to investigate the quality characteristics and antioxidant activities of noodles added with red lentil powder (RLP). Noodles were prepared by addition of 0, 15, 30, and 45% powder to flour of the basic formulation. RLP noodles were evaluated for their cooking properties (weight, water absorption, volume, and turbidity), color values, texture characteristics, sensory characteristics, and antioxidant activities. The weight, water absorption, and volume of cooked RLP noodles increased according to RLP content. The turbidity values of cooking water increased according to RLP content. The L value of RLP noodles decreased with increasing amounts of RLP, whereas a and b values increased with increasing amounts of RLP. The texture characteristics of RLP noodles decreased compared to those of control noodles except for adhesiveness. Antioxidative activities of RLP noodles significantly increased with increasing RLP content (P<0.05). The sensory preference test revealed that RLP 30% noodles showed the highest scores for smell, taste, chewiness, and overall preferences. It is suggested that RLP 30% noodles could be substituted for wheat flour to improve noodle quality.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.741-744
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• 2008

There are two ways to reduce cement content for a given quality level(strength, workability etc.) in concrete. First, reducing the required paste volume by varying the shape or the grading of aggregates. Secondly, holding the paste volume constant while replacing cement volume with mineral admixtures or mineral fillers. And It will also be proved that the required minimum paste volume is independent of the paste composition, provided the paste composition is in a reasonable range. In this study, therefore, we have an object to determine the required minimum paste volume for a given workability level. For this purpose, we tried the following experiments: vary the paste volume for the three different grading of aggregates and determine the minimum paste volume to achieve a certain level of workability with high-range water reducing admixture.

• Journal of Korean Society on Water Environment
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• v.31 no.6
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• pp.732-738
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• 2015

Water quality in four major river basin in Korea was managed with Total Maximum Daily Load (TMDL) System. The unit watershed in TMDL system has been evaluated with Target Water Quality (TWQ) assessment using average water quality, without considering its volume of water quantity. As results, although unit watershed are obtained its TWQ, its allocated loads were not satisfied and vice versa. To solve these problems, a number of TWQ assessments with using Load Duration Curve (LDC) have been studied at other watersheds. The purpose of this study was to evaluate achievement of TWQ with Flow Duration Curve (FDC) and Load Duration Curve(LDC) at 26 unit watersheds in Han river basin. The results showed that achievement rates in TWQ assessment with current method and with LDC were 50~56 % and 69~73%, respectively. Because of increasing about 20% of achievement rates with using LDC, the number of exceeded unit watershed at Han river Basin was decreased about 4~6 unit watersheds.

• Korean journal of food and cookery science
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• v.3 no.1
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• pp.20-30
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• 1987

Kyongdan is a kind of Korean rice cake made from glutinous rice powder. This study attempted to clarify the factors which affect the textural characteristics, and to examine the effects on sensory characteristics and texture of Kyongdan in various soaking time, temperature and volume of adding water in the preparation of Kyongdan. Evaluation was conducted through sensory evaluation and objective evaluation. The degree of gelatinization in various storage time and temperature were evaluated by $\beta$-amylase digestibility. The results were summarized as follows. 1. In preparation, the significant factors were the temperature and volume of water, number of kneading, condition of powder, and the relationships between soaking time and temperature of water and between volume and temperature of water and between volume of water and number of kneading and between volume of water and salt. 2. In sensory evaluation on the various soaking time and temperature and volume of water, the most favorite tendency on the overall quality was at the addition level of hot water of 25% with glutinous rice powder made by soaking for 12 hours. This condition corresponded to the low level of hardness, gumminess, chewiness and the high level of springiness and cohesiveness in comparision with Instron measurement. 3. The degree of gelatinization were decreased rapidly during two days of storage. In storage temperature, Kyongdan which was stored at $0^{\circ}C$, showed the most low level of the degree of gelatinization at the same storage time.

• Journal of Korean Society on Water Environment
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• v.23 no.6
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• pp.807-813
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• 2007

Settling velocity is one of major parameters determining algal biomass in water quality modeling. In this study, the settling velocity of phytoplankton was measured in reservoir and stream sites of the Nakdong River, Korea. Settling velocities of various phytoplankton species were determined by measuring algal cell biomass settled in a sedimentation cylinder. Mean settling velocities were $0.22m\;day^{-1}$ in reservoir sites and $0.33m\;day^{-1}$ in stream sites, which were relatively higher compared with other default values suggested by water quality models (e.g. $0.1m\;day^{-1}$ in CE-QUAL-W2). The lower settling velocity in reservoirs than in stream implies the adaptation of phytoplakton to low turbulence in lentic environments. Cyanobacteria showed lower settling velocity ($0.2m\;day^{-1}$) than diatoms ($0.3m\;day^{-1}$), and this phenomenon may have resulted from buoyancy mechanisms of cyanobacteria. Cell volume did not show a significant correlation with settling velocity in this study, implying that conformation factors of colonies or other factors had large effects on settling velocity of algal cells as well as cell size. The result of this study may suggest proper coefficients of settling velocity of phytoplankton in the calibration of water quality model.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.5
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• pp.712-719
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• 2014

This study was carried out to evaluate the effects of trehalose on quality characteristics of white pan bread. Basic formula consisted of bread flour, 6% sucrose, and 0, 2, 4, 6% trehalose, respectively. Loaf volume, specific loaf volume, baking loss rate, moisture content, water activity, crumb color, and sensory evaluation scores were determined for quality characteristics of bread. White pan bread containing 4% trehalose had a higher loaf volume of 2,140 mL and specific loaf volume of 3.96 mL/g. Baking loss rate of white pan bread was the lowest in the loaf containing 6% trehalose. In crumb texture analysis, hardness of loaf containing 4% of trehalose was the lowest after 7 days of storage. Moisture content and water activity of white pan breads increased with increasing level of trehalose. Color of crumbs was the brightest in the loaf containing 6% trehalose. White pan bread containing 4% trehalose scored better in the sensory evaluation than the others. As a result, trehalose affected quality characteristics of white pan bread. Especially, the addition of 4% trehalose to white pan bread had beneficial effects on quality characteristics.

• Preventive Nutrition and Food Science
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• v.11 no.3
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• pp.243-252
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• 2006

White salted noodles and pan bread were prepared from Korean wheats with 1Dx2.2+1Dy12 subunits in high molecular weight glutenin subunits (HMW-GS) to evaluate the suitability for end-use products through the comparison with US wheats with various classes and commercial wheat flours. Korean wheat flours with 1Dx2.2+1Dy12 subunits showed higher SDS sedimentation volume than US wheat flours with similar protein content. Compared to wheat flours with similar protein content and SDS sedimentation volume, water absorption percent of Korean wheat flours using a mixograph was higher than that of US wheat flours, but similar to commercial wheat flours. Mixograph mixing time was similar to hard wheat flours and commercial noodle flours. Optimum water absorption percent of noodle dough from Korean wheat flours was higher than that of US wheat flours. Noodle sheets from Korean wheat flours with 1Dx2.2+ 1Dy12 subunits showed lower L values, higher a values and similar b values compared to commercial noodle flours. Hardness of cooked noodles from Korean wheat flours 1Dx2.2+1Dy12 subunits correlated positively with protein content, NIRS hardness, mixograph water absorption and gluten yield of flours. Korean wheat flours with 1Dx2.2+1Dy12 subunits showed lower loaf volume and harder crumb firmness than hard wheat flours and commercial bread wheat flours in spite of similar protein quantity and quality to hard wheat flours.

• Journal of Korean Society on Water Environment
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• v.24 no.3
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• pp.333-339
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• 2008

This study was carried out to assay the relationships between empirical factors and water quality in 23 agricultural reservoirs. Based on the trophic state index (TSI) deviation analysis, phosphorus in type II and III was the primary limiting factor on algal growth. BOD, COD, TP and chl.a concentration in type III reservoirs showed higher concentration than those of other types, while SS and TN concentration was no noticeable difference among three types. Characteristics of type III reservoirs showed large reservoir surface and drainage area, large surface area to volume (SAV) ratio, small drainage area to reservoir area (DA/RA) ratio, relatively old age, large paddy field and upland field to drainage area ratio (Mean 17.4%) and high generation and discharge loads compared to other types of reservoirs. In type I and II reservoirs, trends of BOD, TN, TP concentration in water column, were similar to those of the discharge load of pollutants. Although type II reservoirs generally showed low phosphorus discharge loads compared to type I reservoirs, TP and chl.a concentration in water column was greater than that of type I. Characteristics of type II reservoirs showed relatively large SAV ratio and old age compared to type I reservoirs and was similar to those of type III including eutrophic reservoirs.

• Journal of Wetlands Research
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• v.18 no.1
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• pp.100-112
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• 2016

In recent, the direction of water resources policy is changing from the typical plan for water use and flood control to the sustainable water resources management to improve the quality of life. This change makes the information related to water resources such as data collection, management, and supply is becoming an important concern for decision making of water resources policy. We had analyzed the structured data according to the purpose of providing information on water resources. However, the recent trend is big data and cloud computing which can create new values by linking unstructured data with structured data. Therefore, the trend for the management of water resources information is also changing. According to the paradigm change of information management, this study tried to suggest an application of big data and cloud computing in water resources field for efficient management and use of water. We examined the current state and direction of policy related to water resources information in Korea and an other country. Then we connected volume, velocity and variety which are the three basic components of big data with veracity and value which are additionally mentioned recently. And we discussed the rapid and flexible countermeasures about changes of consumer and increasing big data related to water resources via cloud computing. In the future, the management of water resources information should go to the direction which can enhance the value(Value) of water resources information by big data and cloud computing based on the amount of data(Volume), the speed of data processing(Velocity), the number of types of data(Variety). Also it should enhance the value(Value) of water resources information by the fusion of water and other areas and by the production of accurate information(Veracity) required for water management and prevention of disaster and for protection of life and property.