• Food Science and Biotechnology
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• 제15권6호
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• pp.860-865
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• 2006

The quality parameters of sponge cake supplemented with soy protein concentrate (SPC) were evaluated. The addition of SPC to wheat flour increased the protein content and alkaline water retention value, but decreased the sedimentation value. Protein content had a positive correlation with the alkaline water retention value, and a negative correlation with the sedintentation value. The higher the concentration of SPC, the higher the RVA pasting temperature and the lower the viscosity. Increasing the level of SPC in flour led to a decrease in mixogram peak time, whereas peak height, width at peak, and width at 8 min progressively increased. As the amount of SPC increased in the formulation, the pH and specific gravity of cake batter increased, whereas the volume and specific volume of sponge cake decreased. The total isoflavones content in SPC increased after heat treatment. The hardness, gumminess, and chewiness increased progressively in accordance with increasing level of SPC.

• 상하수도학회지
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• 제34권3호
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• pp.211-220
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• 2020

When domestic sewage and rainwater runoff are discharged into a single sewer pipe, it is called a "combined sewer system." The sewage design standards in Korea specify the flow velocity based only on the volume of rainfall; therefore, sedimentation occurs on non-rainy days owing to the reduced flow rate and velocity. This sedimentation reduces the discharge capacity, causes unpleasant odors, and exacerbates the problem of combined sewer overflow concentration. To address this problem, the amount of sewage on non-rainy days, not just the volume of rainfall, should also be considered. There are various theories on sedimentation in sewer movement. This study introduces a self-cleansing velocity based on tractive force theory. By applying a self-cleansing velocity equivalent to the critical shear stress of a sand particle, sedimentation can be reduced on non-rainy days. The amount of sewage changes according to the water use pattern of citizens. The design hourly maximum wastewater flow was considered as a representative value, and the velocity of this flow should be more than the self-cleansing velocity. This design method requires a steeper gradient than existing design criteria. Therefore, the existing sewer pipelines need to be improved and repaired accordingly. In this study, five types of improvement and repair methods that can maximize the use of existing pipelines and minimize the depth of excavation are proposed. The key technologies utilized are trenchless sewer rehabilitation and complex cross-section pipes. Trenchless sewer rehabilitation is a popular sewage repair method. However, it is complex because the cross-section pipes do not have a universal design and require continuous research and development. In an old metropolis with a combined sewer system, it is difficult to carry out excavation work; hence, the methods presented in this study may be useful in the future.

• 한국농공학회지
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• 제17권3호
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• pp.3840-3847
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• 1975

With 30 excisting reservoirs in the Chin-Young area, the Sedimentation of the reservoirs has been calculated by comparing the present capacity with the original value, which revealed its reduced reservoir capacity. The reservoirs has a total drainage area of 3l4l ha, with a total capacity of 43.23 ha-m, and are short of water supply due to reduction of reservoir capacity, Annual sedimentation in the reservoir is relation to the drainage area, the mean of annual rainfall, and the slop of drainage area. The results of obtained from the investigation are summarized as follows: (1) A Sediment deposition rate is high, being about 7.03㎥/ha of drainage area, and resulting in the overage decrease of reservoir capacity by 16.1%. This high rate of deposition coule be mainly attributed to the serve denudation of forests due to disorderly cuttings of tree. (2) An average unit storageof 116mm as the time of initial construction is decreased to 95.6mm at present. This phenomena cause a greater storage of irrigation water, sinceit was assumed that original storage quantity itself was already in short. (3) A sediment deposition rate as a relation to the capacity of unit drainge area is as follow: Qs=1.27(C/A)0.6 and standard deviation is 185.5㎥/$\textrm{km}^2$/year. (4) A sediment deposition rate as a relation to the mean of annual rainfall is as follow: Qs=21.9p10.5 and the standard deviation is 364.8㎥/$\textrm{km}^2$/year. (5) A sediment deposition rate as a relation to the mean slop of drainage area is follow: Qs=39.6S0.75 and the standard deviation is 190.2㎥/$\textrm{km}^2$/year (6) Asediment deposition rate as a relation to the drainage area, mean of rainfall, mean of slope of drainage area is: Log Qs=0.197+0.108LogA-6.72LogP+2.20LogS and the standard deviation is 92.4㎥/$\textrm{km}^2$/year

• 한국환경과학회지
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• 제18권3호
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• pp.289-298
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• 2009

The blue-green algae which caused odor problem in the tap water are difficult to precipitate in sedimentation basin and clogged the filter void rapidly. The studies of this paper were not only oxidation, coagulation and sedimentation processes for effectively removing blue-green algae but yellow clay and polyamine for verification as coagulants aids. The results of this research are summarized as follows: Higher ozone dose(C) and longer contact time(T) were needed for a high degree of removing blue-green algae efficiency. the removal rate of blue-green algae was proportional to the $C\times T$ value. The removal percent of chlorophyll-a by sedimentation and filter without pre-ozonation was about 75% but 1 mg/L pre-ozonation could increase the removal percent of chlorophyll-a to 99% and more pre-ozonation could remove completely. Though the removal efficiency of turbidity could increased by high dose of chlorination, the dissolved organic carbon was increased. More chlorine dose from 4 to 10 mg/L dissolved organic carbon was decreased. Using yellow clay as coagulant aids increased density of floc so the settling velocity of floc become rising but polyamine could not increase settling velocity of floc though it could formated large floc.

• 상하수도학회지
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• 제19권4호
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• pp.429-436
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• 2005

A coagulation/ultrafiltration membrane hybrid system was operated to treat river water with capacity of $0.06m^3/d$. The impact on membrane fouling by flux and linear velocity was investigated. It is known that pressure increase is proportional to flux increase. However, pressure increase was much faster than theoretical value in the pilot plant test. So it was suggested that flux was on important factor in ultrafiltration of continuous operation. Membrane fouling was decreased when linear velocity was increased. This phenomenon was found more obviously without coagulation. With the combination of coagulation and sedimentation, membrane fouling was not reduced conspicuously. Big particles formed during coagulation and sedimentation were destroyed by feed and circulation pumping, which resulted in little effect on membrane fouling reduction. The degree of destruction was similar at various linear velocities. In this study, the hollow fiber membrane was used and the system was operated in pressure type module. In case of the system used in this study, membrane fouling has been affected lightly by linear velocity variation when coagulation pretreatment was applied.

• 대한수의학회지
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• 제27권2호
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• pp.339-345
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• 1987

Each of twenty blood samples taken from apparently healthy Korean Cows was used to produce five different mixtures of autologous plasma and blood corpuscles such that their values of packed cell volume (PCV) lay between 10 to 50ml/l00ml. The measurements of erythrocyte sedimentation rate (ESR) using 45 degree-angled capillary hematocrit tube, 1.1-1.2mm bore, ($45^{\circ}-micro-ESR$) were practised for the blood of various levels of PCV under the ambient temperature of ${10^{\circ}C}$, ${20^{\circ}C}$ and ${30^{\circ}C}$. Correlation of ESR to ambient temperature showed linear regression each in five levels of PCV. ESR increased with ascending ambient temperature, and magnitude of the increase of ESR became greater as the level of PCV lowered. Correlation of ESR, of which values were transformed by the linear regression equation correlated to ambient temperature to PCV showed curvilinear regression each in three levels of ambient temperature, and ESR was increased with decreasing PCV. The data were statistically analysed and a list of relative anticipate $45^{\circ}-micro-ESR$ values for PCV and ambient temperature was presented.

• 대한수의학회지
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• 제28권1호
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• pp.187-192
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• 1988

Each of twenty blood samples taken from apparently healthy Korean cows was used to produce five different mixtures of autologous plasma and blood corpuscles such that their values of packed cell volume(PCV) lay between 10 to 50ml/100ml. The measurement of erythrocyte sedimentation rate (ESR) using 45 degree-angled Wintrobe hematocrit tube, 3mm bore, ($45^{\circ}$-Wintrobe-ESR) was practiced for the blood of various levels of PCV under the ambient temperature of $10^{\circ}C$, $20^{\circ}C$ and $30^{\circ}C$. Correlation of the ESR to the ambient temperature showed linear regression each in five levels of PCV. The ESR increased with ascending ambient temperature, and magnitude of the increase of the ESR became greater as the level of PCV lowered. Correlation of the ESR to PCV showed curvilinear regression each in three levels of the ambient temperature, and the ESR was increased with decreasing PCV. The data were statistically analysed and a list of relative anticipated $45^{\circ}$-Wintrobe-ESR values for PCV and ambient temperature was presented.

• 상하수도학회지
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• 제12권1호
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• pp.81-87
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• 1998

The possibility of collision of two particles slowly settling one after another in water can be described using the collision efficiency factor in differential sedimentation (${\alpha}_{DS}$). ${\alpha}_{DS}$ was found to be a function of several parameters particle size, particle size ratio, Hamaker constant, density of liquid and particle, gravity acceleration. Previous researches were limited to the case when there is no electric repulsion assuming that the suspension is destabilized. In this paper, ${\alpha}_{DS}$ is calculated for the stabilized condition. The relative trajectory of two particles are calculated including hydrodynamics, attraction and repulsion forces. Ionic strength and surface potential significantly affect the collision possibility of two settling particles. Depending on the surface potential and ionic strength, ${\alpha}_{DS}$ value is divided into three regions; stable, unstable and transition zone. ${\alpha}_{DS}$ increases as the ionic strength increases, and as the surface charge decreases. This result can be used to model both destabilized and stabilized suspension incorporating the collision efficiency factors of the other coagulant mechanisms such as fluid shear and Browian motion.

• 물과 미래
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• 제9권2호
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• pp.67-75
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• 1976

With 9 existng reservoirs selected in the Sab-Gyo River Basin, the sedimentation of the reservoirs has been calculated by comparing the present capacity with the original value, which revealed its reduced reservoirs capacity. The reservoirs has a total drainage area of 6,792 ha, with a total capacity of 1,204.09 ha-m, and are short of water supply due to reduction of reservoirs capacity. Annual sedimention in the reservcire is relation to the drainage area, the mean of annual rain fall, and the slop of drainage area. The results of obtained from the investigation are summarized as follow; (1) A sediment deposition rate is very high, being about $9.19{m}^3/ha$ of drainage area, and resulting in the average decrease of reservoir capacity by 19.1%. This high rate of deposition could be mainly attributed to the serve denvdation of forests due to disor derly cuttings of tree. (2) An average unit storage of 415.8mm as the time of initial construation is decreesed to 315.59mm at present, as resultting, we could'nt supply water at 566.24ha. (3) A sediment deposition rate as a relation to the capacity of unit drainage area is as follow; $Qs=1.43 (c/a)^{0.531}$ (4) A sediment deposition rate as a relation to the mean of annval rainfall is as follow; $Qs=672.61 p^{0.024}$ (5) A sediment deposition rate as a relation to the mean slop of drainage area is follow; $Qs=267.21 S^{0.597}$

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2023년도 학술발표회
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• pp.38-38
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• 2023

Pleikrong reservoir with a concrete gravity dam that impound more than 1 billion cubic meter storage volume is one of the largest reservoir in Central Highland of Vietnam. Sedimentation is a major problem in this area and it becomes more severe due to the effect of climate change. Over time, it gradually reduces the reservoir storage capacity affecting to the reliability of water and power supply. This study aims to integrate the soil and water assessment tool (SWAT) model with 14 bias-corrected GCM/RCM models under two emissions scenarios, representative concentration pathway (RCP) 4.5 and 8.5 to estimate sediment inflow to Pleikrong reservoir in the long term period. The result indicated that the simulated total amount of sediment deposited in the reservoir from 2010 to 2018 was approximately 39 mil m³ which is a 17% underestimate compared with the observed value of 47 mil m³. The results also show the reduction in reservoir storage capacity due to sedimentation ranges from 25% to 62% by 2050, depending on the different climate change models. The reservoir reduced storage volume's rate in considering the impact of climate change is much faster than in the case of no climate change. The outcomes of this study will be helpful for a sustainable and climate-resilient plan of sediment management for the Pleikrongreservoir.