• Journal of Environmental Health Sciences
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• v.15 no.1
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• pp.51-62
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• 1989

This survey was performed to investigate contamination degree and significance in each item of 406 samples of ground water, which was collected in Seoul area from Jan. to Dec. 1988. The results of this study were as follows 1. The unsuitable rate of ground water investigated was 69.7%(32.4% in only bacteria, 23.6% in both bacteria and physico-chemistry and 13.6% in only physico-chemical contamination). 2. The unsuitable rate in each item was the highest(54.2%) in standard plate countland 29.8% in coliform, 12.8% in turbidity, 11.3% in Zn, and 10.8% in Mn. 3. The total mean concentrations in each item were lower than standard except standard plate count, coliform, and Fe. 4. In the analysis of corelation, among items, both total hardness and residual solids were showed very high correlationship (P < 0.01) with other items, and both S.P.C. and coliform showed very highly significant (P < 0.01) with NH$_3$-N.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.667-669
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• 2003

A bio-optical model was developed specific for turbid and shallow waters. Special studies were carried out to estimate absorption and scattering properties as well as backscattering probability of suspended matter. The inversion of bio-optical model allows for direct retrieval of turbidity and chlorophyll- a from the visible-near infrared (VNIR) range sensor. Time-series satellite imagery from ASTER AM-1 sensor, were used to monitor the Laguna de Bay water quality condition. Spatial distribution of temperature for the lake was extracted from the thermal infrared (TIR) sensor. Corresponding field surveys were conducted to parameterize the bio -optical model. In-situ measurements include suspended particle and chlorophyll-a concentrations profiles from nephelometric devices and processing of water samples. Hyperspectral measurements were used to validate results of the bio -optical model and satellite- based estimation. This study provides a theoretical basis and a practical illustration of applying space- based measurements on an operational basis.

• Food Science and Biotechnology
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• v.15 no.4
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• pp.564-571
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• 2006

In order to improve the quality and preservation of nabakkimchi, omija was added as an ingredient to determine its effect on the physicochemical characteristics of kimchi during fermentation, as well as the optimum level of omija extract. Omija extract was prepared from omija seeds by extraction with water for 9 hr at room temperature in concentrations (w/v) of 0.5, 1.0, 1.5, and 2.0% for use as an ingredient in nabakkimchi. The physicochemical characteristics of nabakkimchi containing omija extract were analyzed during fermentation of the product for up to 25 days. Delayed fermentation was observed, particularly in the early stage of fermentation, and was dependent on the concentration of the omija extract, as shown by stabilization of pH decreases and increases in the total acidity. An increased concentration of omija extract also raised the initial total vitamin C content and the reducing sugar content, which both then stabilized thereafter. Delayed development of turbidity within the optimum fermentation period of 16 days, increased redness and total color difference, and an electron-donor effect were also promoted by the omija extract. However, the omija extract also triggered extra tannin production, which leads to an astringent taste, especially at the 1.5 and 2.0% treatment levels.

• Preventive Nutrition and Food Science
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• v.1 no.2
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• pp.159-167
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• 1996

Effect of covering various levels(0, 1, 3, 5 and 7% per Chinese radish weight) of bamboo(Pseudosasa japonica Makino) leaves on the surface of Dongchimi was studied in the course of fermenting at 1$0^{\circ}C$ up to 75 days. Physicochemical, microbiogical, and sensory characteristics of Dongchimi were analyzed at regular intervals of 5 to 7 days during fermentation. Both the degree of pH drop from the initial 6.47~6.54and increase total acid content from the initial 0.004%, with the accumulation of organic acids tended to be more gradual depending upon the amounts of bamboo leaves covered. The increases of total solid content and turbidity were also suppressed in similar patterns, notably after 13 days of fermentation. The growth of total bacteria(1.5$\times$10$^4$cfu/ml, initial)was partly inhibited while that of lactic acid bacteria(1.8$\times$10$^4$cfu/ml, initial)was favorably encouraged by the presence of bamboo leaves. As a result of sensory evaluation, Dong-chimi covered with 1 and 3% bamboo leaves on showed the higher scores significantly(p<0.05, p<0.01, p<0.001) in overall acceptability till 39 days. But after 61 days, those covered with 3 and 5% bamboo leaves were rather preferable than any other one.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.6
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• pp.760-767
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• 2013

This study investigated the quality of noodles containing different amounts of collagen powder. Noodles were prepared at ratios of 1, 3, 5 and 7% collagen power based on flour weight. The water binding capacity of the collagen powder was higher than that of flour. The rate of weight increase and volume increase of the noodles as well as the pH and turbidity of the soups were significantly increased with increasing amounts of collagen powder. The noodles showed decreased L and a values, and increased b values with increasing collagen powder in the flour composite. Hardness, springiness and chewiness of cooked noodles increased significantly with the increase in collagen powder content. cohesiveness and brittleness decreased with increasing amounts of added collagen powder. DPPH radical scavenging activity was improved significantly the addition of the collagen powder. Finally sensory evaluation results indicated that the noodles containing 1, 3% collagen powder had higher quality as compared to the other samples. Overall the results suggest that collagen powder is effective for improving the appearance and texture of noodles.

• Journal of Environmental Health Sciences
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• v.37 no.6
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• pp.467-473
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• 2011

Objectives: Wastewater treatment plants typically produce a large volume of waste sludge. In this study, the conditioning and dewatering properties of a digested and thickened sludge from an industrial wastewater treatment plant were investigated in order to improve the dewaterbility of the sludge. Methods: Jar-tests and Buchner funnel tests were carried out to assess the conditioning and dewatering properties of a waste sludge. TTF (Time to Filter Test) and SRF (Specific Resistance to Filtration) were adopted as the indices of sludge dewaterbility. Results: The valuation indices influencing the dewaterbility of the waste sludge, including TTF, SRF, water contents, VS/TS ratio and turbidity, were measured. The TTF and SRF of the digested and thickened sludge were decreased to 40 sec, $3.43{\times}10^{12}$ m/kg, and 39 sec, $1.09{\times}10^{12}$ m/kg, respectively. Conclusions: The conditioner composed of natural inorganic materials turned out to be effective in the reduction of sludge water contents.

• Journal of the Korean Society of Food Culture
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• v.28 no.3
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• pp.312-319
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• 2013

This study investigated the quality of noodles containing different amounts of Lagocephalus lunaris powder (LLP). Noodles were prepared at ratios of 0, 1, 3, 5 and 7% LLP based on flour weight, after which cooking quality, mechanical texture properties, and viscosity were measured, and a sensory evaluation was performed. The gelatinization points of the composite LLP-wheat flours were shown to increase. Additionally, measurement of the viscosity at 95, viscosity at 95 after 15 minutes, and the maximum viscosity values decreased, as the LLP content increased. As increasing amounts of LLP were added, the L and a values decreased, whereas the b value increased and the color values, weight, and volume of cooked noodle increased, as did the turbidity of the soup. Finally the LLP additive increased hardness and decreased adhesiveness, cohesiveness and springiness. Sensory evaluation showed that high quality cooked noodle could be produced by inclusion of 5% LLP.

• Membrane and Water Treatment
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• v.5 no.2
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• pp.73-86
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• 2014

Membrane fouling is a major challenge limiting the use of membrane applications. In this study high induced shear rates were utilized at the membrane surface in order to reduce the organic and inorganic scaling by using the torsional vibration of flat sheet membranes. The performances of a vibratory shear-enhanced processing (VSEP) system for the ultrafiltration (UF), nanofiltration (NF) and reverse osmosis (RO) membrane filtration of industrial dairy wastewater were investigated. The vibration and non-vibration methods were compared with the same membrane and operational parameters during the purification of real dairy industrial process wastewater. In the initial experiments, short-term tests were carried out in which the effects of vibration amplitude, recirculation flow rate and transmembrane pressure were measured and compared. The permeate flux, turbidity, conductivity and chemical oxygen demand (COD) reduction of dairy wastewater were investigated by using UF, NF and RO membranes with vibration and non-vibration methods. In the subsequent experiments, concentration tests were also carried out. Finally, scanning electron microscopy (SEM) revealed that the vibration method gave a better performance, which can be attributed to the higher membrane shear rate, which reduces the concentration of solids at the membrane, and the transmission.

• Journal of Korean Society of Water and Wastewater
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• v.20 no.4
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• pp.585-594
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• 2006

This study focused on the causes of fish kills and its prevention methods in Yudeung Stream, Daejeon, Korea. Intense field data, continuous water quality monitoring system and water quality modeling were applied to analyze the causes. Pollutant can be delivered to urban streams by surface runoff and combined sewer overflows in rainfall events. However, water quality analysis and water quality modeling results indicate that the abrupt fish kills in the Yudeung stream seems to be caused by combined effect of DO depletion, increase in turbidity and other toxic material. Excessive fish population in the study area may harm the aesthetic value of the stream and also has greater potential for massive fish kills. It is suggested to implement methods to reduce delivery of pollutants to the stream not only to prevent fish kills but also to keep balance of ecosystem including human uses. Frequent clean up of the urban surface and CSO, installation of detention basin will be helpful. In the long run, it seems combined sewer system has be replaced with separate sewer system for more effective pollutant removal in the urban area.

• Ocean and Polar Research
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• v.24 no.3
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• pp.289-300
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• 2002

The Lago Sofia conglomerates encased in the Cretaceous Cerro Toro Formation, southern Chile, represent a gigantic submarine channel system developed along a foredeep trough. The channel system consists of several tributaries along the trough margin and a trunk channel along the trough axis. Voluminous debris flows were generated ubiquitously along the tract of the submarine channel mainly by the failure of nearby channel banks or slopes. The flows transformed immediately into multiphase flows and resulted in very thick-bedded mass-flow deposits with a peculiar structure sequence. The mass-flow deposits commonly overlie fluted or grooved surfaces and consist of a lower division of clast-supported and imbricated pebble-cobble conglomerate with common basal inverse grading, and an upper division of clast- to matrix-supported and disorganized pebble conglomerate or pebbly mudstone with abundant intraformational clasts. The structure sequence suggests a temporal succession of a turbidity current, a bipartite hyperconcentrapted flow with active clast collisions near the flow base, and a cohesive debris flow probably with a rigid plug. The multiphase flow is interpreted to have resulted from transformation of clast-rich but cohesive debris flows. Cohesive debris flows appear to transform more easily into dilute flow types in subaqueous environments because they are apt to hydroplane. This is in contrast to the flow transitions in subaerial environments where noncohesive debris flows are dominant and difficult to hydroplane.