• 대한의용생체공학회:의공학회지
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• 제3권1호
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• pp.9-16
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• 1982

Removal of urea and vitamin B12 was simulated using two pool models with closed loop dialysis, open loop dialysis, and hemodiafiltrations with predilution and postdilulion. It was found that urea removal was limited by dialyzer clearance, however B12 removal was limited both by the resistance between ECF and ICF and by dialyzer clearance. Open loop dialysis was better than closed loop dialysis in terms of dialysate requirement and removal efficiency. Residual renal function plays an important role in removing vitamin B12. Dialysis frequency more than twice/wide does not have great effect on removal efficiency, but has the effect of reducing the difference between maximum and minimum cancentrations during dialysis period.

• 한국수산과학회지
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• 제50권3호
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• pp.250-256
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• 2017

This study investigated the removal efficiency of organic matter and nitrogen from fish farm effluent by hydraulic retention time (HRT) using an upflow biological filter (ANR system) reactor. The recycling time and influent flow in the reactor were controlled to 14.8, 7.4, 5.5 and 3.2 h to evaluate HRT. In addition, each reactor was coupled to a fixed bed upflow filter charged with media. The results showed that removal efficiency was ${\geq}95%%$ with an HRT of 5.5 h, and nitrification efficiency was reduced to 81% with an HRT of 3.2 h, although nitrification efficiency temporarily decreased due to the shock load as HRT decreased. Total nitrogen removal rate was also reduced to about 65% with an HRT of 3.2 h, which was considered a washout effect of nitrifying and denitrifying microorganisms by increasing the shearing force to the filter media, which decreased organic matter and nitrogen removal efficiency.

• 환경위생공학
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• 제15권2호
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• pp.41-48
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• 2000

In this study, we have investigated the effect of the various operating conditions on the removal fluorine in the rinsed water for the semiconductor industry by using electrolysis process. The removal efficiency of fluorine was irrelevant to initial pH, and carbon anode was high-level treatment in the effect of various electrodes. Fluorine included in the wastewater is treated by the addition of a Ca(OH)2, removal efficiency of electrolysis was increased about 40%. Besides the removal efficiency of fluorine was increased as the current density was increased and this treatment system could reduce both the total sludge and running costs. The feasibility of the electrochemical treatment to the fluorine containing wastewater was verified from this study.

• 산업기술연구
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• 제21권A호
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• pp.279-284
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• 2001

In this study, we analyzed the $NO_X$ removal effiency by the low temperature plasma process and investigated the effect of several process variables. Most of NO is converted into $NO_2$ and, later, into $HNO_3$ which reacts with $NH_3$ to form $NH_4NO_3$ particles. As the frequency of appling voltage increases, as the applied voltage increases or as the residential time increases, removal efficiency of the NO supplied initially increase. The removal efficiency of $NO_X$ also increases with the increase of $NH_3$ supplied.

• 상하수도학회지
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• 제22권4호
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• pp.461-466
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• 2008

Because of their simplicity, efficiency, and economy, slow sand filters are appropriate means of water treatment for small water systems. In this study, the effect of filtration velocity and dirty skin (Schmutzdecke) was evaluated on the performance of turbidity removal. Also, removal characteristics of particulate were investigated in the case of the usage of non-woven fabric on the surface of sand and the application of PCF as pretreatment process. Comparative column tests were carried out for the various operation condition. From the result of column tests, filtration velocity had little effect on the turbidity removal rate. The formation of algal biofilm on the surface of media is helpful in turbidity removal, while non-woven fabric is not as effective as expected. The relative contribution of biomass and accumulated particulates to head loss development in slow sand filters requires further study.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2002년도 생물공학의 동향 (X)
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• pp.346-348
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• 2002

This study estimated the effect of influent TAN concentration. temperature and pH in the airlift bioreactor(aeration rate; 1.5 vvm, HRT 0.35hr) using immobilized nitrifiers by PVA. At the effect of influent TAN concentration, removal rate was increased with increasing it and removal efficiency maintained 93${\pm}$2%. The optimum temperature for nitrification was $30^{\circ}C$ and at this point. removal efficiency was 95.5${\pm}$1.5%. It was effective to nitrify at $10^{\circ}C$ of low temperature. In the pH range from 7 to 9 in the bioreactor. removal rate and removal efficiency was 310${\pm}$10 $g/m^3$ day and 94${\pm}$3%.

• 한국식품조리과학회지
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• 제16권5호
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• pp.410-415
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• 2000

본 실험의 목적은 우리나라 상용식품인 쌀과 배추의 세척과 가열에 의한 유기인계 농약의 제거효과를 보기 위한 것으로 유기인계 농약 중 diazinon, fenithrithion, phenthoate, EPN 인위적으로 부착하여 세척과 가열과정의 변화에 의한 저감 효과를 실험한 결과는 다음과 같다. 1. 쌀의 세척에 의한 농약의 제거율은 15.5∼35.4%이었으며, 제거효과는 세척회수보다 물의 양의 영향력이 더 높았다. 2. 쌀을 세척한 후 취반과정을 거치면 농약의 제거율은 72.1∼77.8%이었다. 3. 배추의 세척, 가열과정에 의한 농약의 제거율은 각각 18.4∼41.0%, 22.8∼82.7%이었다. 4. 배추는 쌀과 같이 세척과 가열시 물의 양이 많을수록 제거효과가 높았다. 5. 우리나라의 요리 방법인 나물 무침시 배추를 삶아서 꼭 짜서 수분이 제거되면 농약의 잔존량은 더욱 낮아진다.

• 기술사
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• 제15권3호
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• pp.33-36
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• 1982

Dewaxing Technique was reconized as the removal of waxy materials from the lubriating distillates for the purpose of the improvement of the low temperative fluidity of the lubricating oils. Recently this technique is developed not only the removal of the waxy materials but the reformation of the waxy materials which does not effect the low temperative fluidity of the lutricating oils. The cutalytic dewaxing technique is developed is this letter direction. And so I insist here the defintion of dewaxing technique must be defined as the technique of the removal and reforming technique of the waxy materials which effect the fluidity of the lubricating oils.

• 대한기계학회논문집A
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• 제29권2호
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• pp.341-349
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• 2005

Damage often occurs on the surface of railway wheel by wheel-rail contact fatigue. It should be removed before reaching wheel failure, because wheel failure can cause derailment with loss of life and property. The increase or decrease of the contact fatigue life by the metal removal of the contact surface were shown by many researchers, but it has not explained precisely why fatigue life increases or decreases. In this study, the effect of metal removal depth on the contact fatigue life for railway wheel has been evaluated by applying finite element analysis. It has been revealed that the residual stress and the plastic flow are the main factors determining the fatigue life. The railway wheel has the initial residual stress formed during the manufacturing process, and the residual stress is changed by thermal stress induced by braking. It has been found that the initial residual stress determines the amount of metal removal depth. Also, the effects of the initial residual stress and metal removal on the contact fatigue lift has been estimated, and an equation is proposed to decide the optimal metal removal depth for maximizing the contact fatigue life.

• 한국수산과학회지
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• 제37권1호
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• pp.18-23
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• 2004

Effect of initial protein concentration on the protein removal rate was assessed for seawater aquarium using a foam separator. Protein removal rate was increased and removal efficiency was decreased with the increase of initial protein concentration. Enrichment ratio was decreased and foam generation rate was increased with the increase of initial protein concentration. Total suspended solids (TSS) removal rate was increased with the increase of initial protein concentration, and TSS removal efficiency was decreased with the increase of initial protein concentration. Turbidity removal rate and removal efficiency were increased with the increase of initial protein concentration.