• The Korean Journal of Zoology
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• v.9 no.2
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• pp.1-6
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• 1966

Effects of compound factors (temperature , salinity and turbidity 0 on Tapes philippinarum are as follows : 1. At 3 and 6 hours , critical temperature of 0.9-1.05 mm size is 38$^{\circ}C$ and 7.5-8.5mm, 23-25 mm exist between 35$^{\circ}C$ and 41$^{\circ}C$. 2. The main limiting factor of three combined factors is temperature. The effect on the survival of Tapes philippinarum is as follows : Temperature > salinity > turbidity. 3. In the worst condition, treatment time is also an important factor. Mortality is higher at 6 hour treatment than 3 hour. 4. We observed 39$^{\circ}C$ of water temperature at Tapes bed of Inchon in July 1965. Compared with experimental results, we are able to suppose that the mortality will be occurred at high degrees in the natural state. 5. As the size of the individual is increased , the survival rate is increased as well.

• Proceedings of the Membrane Society of Korea Conference
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• 2008.05a
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• pp.134-137
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• 2008

• Journal of Korean Society of Water and Wastewater
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• v.22 no.5
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• pp.517-522
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• 2008

This study aims at an assessment of the effectiveness of taste & odor removal and transmembrane pressure changes in a pilot membrane plant(500m3/day) by adding PAC to MF process, and at providing a basis for applying it to the advanced water treatment process. The transmembrane pressure showed, in low turbidity of raw water, a tendency to decrease when PAC was injected at the Flux of 1, $1.5m^3/m^2{\cdot}d$, while it increased in high Flux($1.5m^3/m^2{\cdot}d$) in high turbidity of raw water. in addtion, it is shown that the fouling could be reduced more when PAC is injected together with appropriate amount of coagulant, than when PAC is solely injected. Taste & Odor-causing 2-MIB may not be detected in membrane filtered water, if the amount of PAC injection is increased in accordance with the increasing concentration of 2-MIB. Hence, PAC injection, as a pre-treatment process in MF membrane filtering, is supposed to be a suitable process for reducing fouling as well as for improvement effectiveness of taste & odor treatment.

• Journal of Korean Society of Water and Wastewater
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• v.11 no.1
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• pp.81-87
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• 1997

Coagulation is very important process in water works. The subsequent processes are directly affected by this process. Many factors such as turbidity, alkalinity, pH, hardness, total organic carbon(TOC), velocity gradient and flocculation time effect on coagulation process. Among these factors, specially TOC is being concerned target substance to be removed due to trihalomenthanes(THMs) precursor and alkalinity is being one of the major parameter for removing TOC. We have researched the consumption of coagulant with TOC alkalinity concentration of water and removal efficiency of residual TOC and turbidity with alkalinity. Furthermore we have investigated particle size distributions with velocity gradient and alkalinity. The consumption of coagulant was proportionally increased to TOC and alkalinity concentration and the removal of TOC in Nakdong river water was very difficult more than 150 mg/l in alkalinity but large morecular weight organic such as humic acid could be removed easily. Coagulation of low alkalinity water was more rapidly occured than of high alkalinity water by analyzing the particle size distributions. High alkalinity water needed higher mixing energy for a good coagulation within limited flocculation time.

• Korean journal of food and cookery science
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• v.25 no.1
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• pp.31-38
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• 2009

The noodle is one of the most popular meal as a main dish in Korea and onions are reported to contain high levels of flavonoids such as quercetin, aglycone, and quercetin 4-glycoside. This study was conducted to develop the wet noodle with onion juice and to examine the cooking quality, textural properties of it. Five sensory attributes such as gloss, chewiness, adhesiveness, odor, and taste were used for sensory evaluations. Optimal amount of onion(149.5 g) and salt (6.5 g) satisfied target sensory score(7.0) was suggested by response surface methodology. The wet noodle with optimal amount of onion juice and salt was tasted by 100 consumer and showed high score(6.67) in overall acceptability. Cooking quality was measured through absorption of water, volume, degree of turbidity. The volume, water absorption, and cooking water turbidity of cooked wet noodle with onion juice(experimental noodle) were significantly(p<0.01) higher than the control one. Texture profile analysis of experimental noodle showed a lower score of hardness, adhesiveness, springiness, and chewiness. However, it appeared that the experimental noodle showed higher score for cohesiveness than the control noodle.

• Journal of Environmental Health Sciences
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• v.38 no.2
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• pp.128-135
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• 2012

Objectives: This study was aimed at determining the optimum coagulation dosage in a high turbid kaolin water sample using streaming current detection (SCD) as an alternative to the jar test. Methods: SCD is able to optimize coagulant dosing by titration of negatively charged particles. Kaolin particles were used to mimic highly turbid water ranging from 50 to 600 NTU, and polyaluminum chloride (PAC, 17%) was applied as a titrant and coagulant. The coagulation consisted of rapid stirring (5 min at 140 rpm), reduced stirring (20 min at 70 rpm), and settling (60 min). To confirm the coagulation effect, a jar test was also compared with the SCD titration results. Results: SCD titration of kaolin water samples showed that the dose of PAC increased as the pH rose. However, supernatant turbidity less than 1 NTU after coagulation was not achieved for high turbid water by SCD titration. Instead, a conversion factor was used to calculate the optimum PAC dosage for high turbid water by correlating a jar test result with that from an SCD titration. Using this approach, we were able to successfully achieve less than 1 NTU in treated water. Conclusions: For high turbid water influent in a water treatment plant, particularly during summer, the application of SCD control by applying a conversion factor can be more useful than a jar test due to the rapid calculation of coagulation dosage. Also, the interpolation of converted PAC dose could successfully achieve turbidity in the treated water of less than 1 NTU. This result indicates that an SCD system can be effectively used in a water treatment plant even for high turbid water during the rainy season.

• 한국해양학회지
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• v.21 no.2
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• pp.101-109
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• 1986

To clarify the light condition which influence phytoplankton ecology in Kyeonggi Bay, light intensity, compensation depth, extinction coefficient, transparency and suspended substances are studied from May 1981 to September 1982.Light intensities lie within adequate values for the phytoplankton growth from spring to autumn. However, in the winter season the light intensities show less than 4.8mw/$\textrm{cm}^2$ on the surface resulting lower than optimum irradiance. Light intensity could be a limiting factor for phytoplankton growth in winter. Compensation depths seasonally varied over an annual period in this study. Especially, in winter, compensation depths are confined to only 1-2m below the surface. Extinction coefficient(K) values are relatively high over an year cycle. K values is highest in winter and lowest in summer. Transparency shows seasonal variation. Tansparency is high in summer and low in winter. Thus low light intensity, low compensation depth, low transparency and high extinction coefficient in winter are due to the high turbidity and high concentrations of suspended substances. High concentrations of S.S. in winter result from the sediments and detritus resuspended by the winter turbulence induced by the strong winter winds and the convectional mixing. In summer, good light condition and low turbidity may result from the thermal stability of water mass preventing the resuspension of sediment particles.

• The Journal of Engineering Geology
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• v.23 no.2
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• pp.161-170
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• 2013

We analyzed the effect of changing water level and turbidity on plants that serve to maintain slope stability on levees. In this experiment, soil collected from upstream of Imha Dam was placed in a water tank and planted with river plants of the Salix species: Salix gracilistyla, S. koreensis, and S. glanduosa. Plant regrowth was analyzed stage-by-stage during a recovery period. In addition, we assessed the tolerance of the plants to concentrated torrential rainfall and examined their recovery rates. The results indicate that in the case of these three Salix species, which are the most prevalent river plants in Korea, stem growth is arrested following serious damage and high turbidity. The possibility of regrowth was very low during the 20-day non-submerged recovery period. Although the number of leaves initially decreased during this period, subsequent regrowth was reasonably high: recovery in S. gracilistyla, S. koreensis, and S. glanduosa was up to 59.3%, 251.3%, and 148.4% respectively, compared with the initial condition.

• Membrane Journal
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• v.21 no.1
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• pp.72-83
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• 2011

For advanced drinking water treatment of high turbidity water, we used the hybrid module that was composed of photocatalyst packing between outside of tubular ceramic microfiltration membrane and membrane module inside. Photocatalyst was PP (polypropylene) bead coated $TiO_2$ powder by CVD (chemical vapor deposition) process. Instead of natural organic matters (NOM) and fine inorganic particles in natural water source, modified solution was prepared with humic acid and kaolin. Water-back-flushing of 10 sec was performed per every period of 10 min to minimize membrane fouling. Resistance of membrane fouling ($R_f$) decreased and J increased as concentration of humic acid changed from 10 mg/L to 2 mg/L, and finally the highest total permeate volume ($V_T$) could be obtained at 2 mg/L. Then, treatment efficiencies of turbidity and $UV_{254}$ absorbance were above 98.5% and 85.7%, respectively. As results of treatment portions by membrane filtration, photocatalyst adsorption, and photo-oxidation in MF, MF + $TiO_2$, and MF + $TiO_2$ + UV processes, turbidity was treated little by photocatalyst adsorption, and photo-oxidation. However, treatment portions of humic acid by adsorption and photo-oxidation were above 10.7 and 8.6%, respectively.

• The Korean Journal of Food And Nutrition
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• v.25 no.4
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• pp.820-826
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• 2012

This is a basic study of Cheong-song mineral water, which has high contents of Ca and Mg for making noodles as well as for general cooking. The test results of the noodles manufactured and cooked with mineral water were compared to those manufactured and cooked with distilled water and tap water. Noodles manufactured with mineral water showed higher values than others in the cooked weight, volume, water absorption ability, turbidity, lightness (L) and redness (a) on the minus scale. This means that we can manufacture cooked noodles that have high weight, high volume, high water absorption ability and high lightness (L) along with a slight green color with Cheong-song mineral water. Cooked noodles manufactured with mineral water showed significant differences in the cooked weight and volume compared to those manufactured with distilled water. Also, cooked noodles manufactured with mineral water showed significant differences in moisture absorption, turbidity, lightness (L), redness (a) and yellowness (b) compared to those manufactured with distilled water and tap water. Commercial noodles cooked in mineral water showed significant differences in the cooked weight and redness (a) compared to those cooked in distilled water and tap water. Further, commercial noodles cooked in mineral water showed significant differences in weight, volume and brightness (L) compared to those cooked in distilled water.