• Journal of Environmental Health Sciences
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• v.36 no.6
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• pp.502-509
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• 2010

In this study, the (phosphorous removal) the characteristics of phosphorous removal due to (the iron compound precipitated) iron compound precipitation by iron electrolysis in (the anoxic. oxic process) anoxic and oxic processes (equipped with the) in an iron precipitation device were analyzed. During the device operation period, the average concentration of BOD, T-N, and T-P were 219.9 mg/l, 54.6 mg/l and 6.71 mg/l, respectively. The BOD/$COD_{Cr}$ ratio was 0.74, and the BOD/T-N and BOD/T-P ratios were 4.0 and 32.8, respectively. The removal rate of (the organic matters) organic matter (BOD and $COD_{Cr}$) was very high at 91.6% or higher, and that of nitrogen was 80.5%. The phosphorous concentration (of the final) in the treated water was 0.43 mg/l (0.05-0.74 mg/l) on average, and the removal efficiency was high at 90.8%. The soluble T-P concentrations in (an) the anoxic reactor, oxic reactor (II) and final treated water were 1.99 mg/l, 0.79 mg/l and 0.43 mg/l, respectively, which indicated that the phosphorous concentration in the treated water was very low. Regardless of the changes in the concentrations of (organic matters) organic matter, nitrogen and phosphorous in the influent, the quality of the treated water was relatively stable and high. The removal rate of T-P somewhat increased with the increase in the F/M ratio in the influent, and it also linearly increased in proportion to the T-P loading rate in the influent. In the treatment process used in this study, phosphorous was removed (using) by the precipitated iron oxide. Therefore, the consumption of organic (matters) matter for biological phosphorus removal was minimized and (most of the organic matters were) was mostly used as the organic carbon source for the denitrification in the anoxic reactor. This (can be an economic) treatment process (without the need for the supply of additional organic matters) is economic and does not require the supply of additional organic matter.

• Journal of the Korean Institute of Telematics and Electronics
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• v.24 no.5
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• pp.813-817
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• 1987

High value sheet resistance (Rs' 1K-33K\ulcorner/) polysilicon resistors were fabricated using double ion implantation with boron as the major dopant and phosphorus compensation. It is observed that Rs sensitivity to the net doping concentration is decreased by one order of magnitude compared to the conventional (boron implanted)polysilicon resistors. The temperature co-efficient of resistance (TCR) measured between 25\ulcorner and 125\ulcorner shows equivalent values to those of non-compensated resistors for the same Rs. A qualitative electrical conductiion mechanism for compensated polysilicon resistor is proposed, based on the existing grain boundary charge trapping theory.

• Journal of Environmental Health Sciences
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• v.21 no.2
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• pp.36-41
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• 1995

In order to treat effectively various type of wastewater discharged from the manufacture factory of organic phosphorous agricultural pesticides by the activated sludge process. The acclimation test of sludge was carried out by the dilution of completely mixed raw wastewater. The results of experiment were obstained as follows. 1. The moderate dilution rate of mixed raw wastewater was founded to about 30 times. 2. The available range of BOD-SS loading was 0.1~0.15 $kg\cdot BOD/kg\cdot SS\cdot day$ and it was similar to the case of extended aeration activated sludge process. 3. After the acclimation of activated sludge, the concentration of MLSS was 2000 mg/L, removal efficiency of BOD more than 90%, and SVI 100, respectively. 4. The oxygen respiratory rate of acclimated sludge was $47 mg\cdot O_2/g\cdot hr$ and this was increased about 5 times than $10 mg\cdot O_2/g\cdot hr$ of ordinary sludge.

• Journal of Environmental Health Sciences
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• v.35 no.3
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• pp.220-225
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• 2009

This study evaluates the water quality of the river near the alpine farmland in the upper Naerin stream, which is a typical stream of the upper Bukhan River with muddy water generation, by the flow examination, it aims to estimate the characteristics of nonpoint sources flowing out from the investigated area and figure out effective methods to reduce them. According to the result of water quality examination, the average BOD of the area not affected by the cultivated land among the areas of the upper Naerin River was 0.47mg/l, and total phosphorous was 0.007mg/l; thus, it maintained the cleanliness level of Ia. The average BOD of the area with the alpine farmland was 0.52mg/l, which was similar to the one of the non-cultivated land. But total phosphorous concentration was 0.023mg/l, which was more than three times higher than the area belonging to level II due to the effect of fertilizer ingredients discharged from the cultivated land. About the loadings of the investigated area generated from each of the pollution sources, BOD was 878.5kg/day and total phosphorous was 79.7kg/day. Moreover, for the load density, BOD was $2.22kg/day.km^2$ and total phosphorous was shown as $0.20kg/day.km^2$. Regarding the rates generated from nonpoint sources like land among the loadings per pollution sources, BOD was 54%, total nitrogen was 91%, and total phosphorous was 73.4%. Therefore, it was shown that most of the nutrients were produced from the nonpoint sources. The level of BOD runoff loading in the Jaun River area, where nonpoint sources were mainly generated, was 37.1kg/day and total phosphorous was 1.33kg/day. The flow rates to the generated amount were estimated as 10.5% and 4.7% each.

• Environmental engineer
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• s.167
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• pp.50-53
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• 2000

The Wastewater from livestock farms shows the high organic concentration which was over 3,000mg/L of BOD concentrationin swine wastewater especially. Also the nitrogen concentration and red tide phenomena with phosphorous. Most of the livestock facilities

• Journal of the Korea Institute of Information and Communication Engineering
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• v.5 no.6
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• pp.1128-1135
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• 2001

In this paper, a new HSG-Si formation technology, "seeding method', which employs Si$_2$H$_{6}$-molecule irradiation and annealing, was applied for realizing 64Mbit DRAMs. By using this technique, grain size controlled HSG-Si can be fabricated on in-situ phosphorous-doped amorphous-Si electrode. The new HSG-Si fabrication technology achieves twice the storage capacitance with high reliability for the stacked capacitors. In this technique, optimum process conditions of the phosphorous concentration, storage polysilicon deposition temperature and thickness of hemispherical grain silicon are in the range of 3.0-4.0E19atoms/㎤, 53$0^{\circ}C$ and 400$\AA$, respectively. In the 64M bit DRAM capacitor using optimum process conditions, limit thickness of dielectric nitride is about 65$\AA$.

• Journal of Korean Society on Water Environment
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• v.28 no.2
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• pp.300-304
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• 2012

It has a limitation to satisfy the phosphorus effluent criteria of 0.2 mg/L which will be reinforced from 2012 with the Biological Nutrient Removal (BNR) process. The chemical coagulation process has been operated in parallel with the biological treatment process for advanced treatment of phosphorous in the developed countries including Europe. However, the coagulation process has some disadvantages such as the desired goal may not be achieved without injecting the optimum dosage of the coagulant. This study developed the automatic control system to inject the optimum dosage of phosphorous coagulant into the coagulation process. The adopted coagulant was 10% Poly Aluminum Chloride (PAC) in this study. The automatic control system developed in this study was adopted for the treatment of the phosphorus from the effluent in SBR process. The automatic control system was composed of the data receiving part, the optimum coagulant dosage control part and the data transmit part. The result of the phosphorous advanced treatment of the SBR effluent using the automatic control system showed the removing efficiency over 95% consistently with the phosphorous concentration under 0.02 ~ 0.15 mg/L. The reproducibility analysis for checking the safety of automatic control system showed more than 95% correlation.

• Journal of the Korean Society of Marine Environment & Safety
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• v.14 no.2
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• pp.105-109
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• 2008

In our country, limiting nutrient is known as phosphorus in the most lakes. Therefore, the removal of phosphorus is a very important process in sewage treatment. However, many of the sewage treatment plants employ the conventional activated sludge process, known to remove $10{\sim}30%$ of phosphorus. Thus, additional phosphorous removal process will be needed. Oyster shells have been known to remove phosphorus in water. The removal efficiency of phosphorus was highest at smallest size of oyster shells and at the highest pH for batch test. The phosphorous removal rate with various calcium concentrations was increased by increasing calcium concentration. At the 20 mg/l of calcium, more than 90% of phosphorous was removed in two hours. The removal efficiency of phosphorous was increased greatly at 300% of recirculation rate. With 300% of recirculation rate, the removal efficiency reached 80% at pH 11. The negative effects of bicarbonate on crystallization were observed in oyster shells. The effects of bicarbonate on rate constant were also investigated by applying these results to experimental equation. The rate constant was decreased at the inverse logarithm bicarbonate concentration.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.2224-2226
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• 2000

In this paper, we tried to figure out the residual stress of Electroless Nickel (EN) films as a function of process conditions: bath temperatures, pH values, and hypophosphorous acid concentrations. The residual stresses of EN films were in the range of - 4 MPa to 250 MPa depending on process conditions and they were very sensitive to phosphorous concentration in EN film and also hypophosphorous acid concentrations in EN bath.

• Journal of Korean Society of Water and Wastewater
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• v.19 no.2
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• pp.193-199
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• 2005

The objective of this study was to investigate the characteristics of adhesion and detachment of algae on various materials of drainage canal in the sedimentation basin. The influence of surface washability, surface roughness, phosphorous concentration was studied using stainless steel, cement block and ceramic panel. The algae attached content of cement block was higher than that of the ceramic coating panel. The attachment varied significantly with respect to exposure time and different materials. the attachment was higher on rough surface (cement block) when compared to smooth surfaces. The content of attached algae increased with increasing phosphorous concentration in water. The detachment efficient of algae was higher on ceramic panel.