• 한국수산과학회지
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• 제27권6호
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• pp.690-695
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• 1994

혐기-호기 체계의 활성오니를 이용하여 폐수로부터 인과 질소를 동시에 제거하는 연구를 행하였다. 혐기적인 조건에서 nitrate 혹은 nitrite의 농도가 거의 0일 때, 제거된 glucose의 양은 orthophosphate의 방출과 직선적인 관계를 나타내었으며, 유입수에서 인과 glucose의 비율이 0.04 이하일 때, 폐수 중의 인은 호기적인 단계에서 거의 제거되었다. 이는 혐기적 단계에서 받은 stress로 인해 호기적 단계에서 받은 stress로 인해 호기적 단계에서 훨씬 많은 양의 인을 흡수한 것으로 생각된다. 혐기적 단계에서의 인의 방출양과 호기적 단계에서의 인의 흡수양은 $NO_x-N$의 농도와는 비례적인 관계가 아니었으며, 더우기, glucose에 대한 $NO_2-N$의 비가 0.37보다 낮을 때, 유입수 중의 무기질소는 완전히 제거되었다.

• 한국환경보건학회지
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• 제28권3호
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• pp.55-63
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• 2002

This study was carried out to treat textile wastewater using anaerobic sludge and aerobic fixed-bed biofilm reactor immobilized with Bacillus sp. dominated activated sludge(Bacillus sp. fraction : 81.5%). The range of influent con-centration of SCOD and soluble color were 1032-1507 mg/1, and 1239-1854 degree, respectively. Continuous treatment experiments were performed with variation of textile wastewater ratio at a same HRT. When textile wastewater ratio was 100%(HRT : 24 hours), The removal efficiency of SCOD and soluble color were 88% and 78%, respectively. When compare aerobic reactor of this study that was immobilized with Bacillus sp. dominated activated sludge to other study that was immobilized with activated sludge, SCOD and soluble color removal efficiency of this study showed a little higher efficiency than immobilized with activated sludge. The Bacillus sp. fraction of initial condition was 81.5%), but the fraction after operation was decreased to 31.8%).

• Membrane and Water Treatment
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• 제3권2호
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• pp.133-140
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• 2012

The overall performance of BNR-MBR, so-called Anoxic-Anaerobic-Aerobic Membrane Bioreactor ($A^3$-MBR), developed for nutrient removal was studied to determine the efficiencies and mechanisms under different solid retention time (SRT). The reactor was fed by synthetic high-rise building wastewater with a COD:N:P ratio of 100:10:2.5. The results showed that TKN, TN and phosphorus removal by the system was higher than 95%, 93% and 80%, respectively. Nitrogen removal in the system was related to the simultaneous nitrification-denitrification (SND) reaction which removed all nitrogen forms in aerobic condition. SND reaction in the system occurred because of the large floc size formation. Phosphorus removal in the system related to the high phosphorus content in bacterial cells and the little effects of nitrate nitrogen on phosphorus release in the anaerobic condition. Therefore, high quality of treated effluent could be achieved with the $A^3$-MBR system for various water reuse purposes.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제1권1호
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• pp.11-17
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• 1997

The treatment performances of anaerobic-aerobic activated sludge process were investigated under various operation conditions. The treatment system proposed in this study gave a relatively stable performance against hourly change of the flow rate and showed a satisfactory removal efficiency of nitrogen and phosphorus compounds under experimental conditions. The average removal efficiency of total nitrogen gradually decreased as the influent total nitrogen concentration was increased. High C/N ratio of the wastewater was required for the complete removal of nitrogen. Glucose as a carbon source was more efficient than starch and the removal ability for all components become higher with the increase of the fraction of glucose.

• 한국물환경학회지
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• 제22권4호
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• pp.639-647
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• 2006

The temperature effect at $20^{\circ}$ and $10^{\circ}$ on the nutrient removal efficiency was evaluated in the combined biological nutrient removal system (CBNR) with anaerobic-intermittent aerobic-oxic reactors. The test was conducted under the conditions of various ratios of intermittent aeration time and distribution of influent raw water to CBNR. The removal efficiencies of organics, nitrogen and phosphorus were a little bit better at $20^{\circ}$ than at $10^{\circ}$. However the large difference of temperature effect on the nutrient removal efficiency between $20^{\circ}$ and $10^{\circ}$ was not appeared because of highly sustained MLSS concentrations in the reactors and controlled intermittent aeration time. In the removal of phosphorus, Mode III (50/70 min in aeration on/off time, 3 times of intermittent aeration) showed more effective compared with short aeration time of Mode IV. In case of N, P removal, the denitrification rate was lower in Mode A with splitted inflow into anaerobic and intermittent aeration basins than in Mode B with sole inflow into anaerobic basin.

• 한국축산시설환경학회지
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• 제21권1호
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• pp.21-28
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• 2015

We studied the possibility on the application of the Thermophilic Aerobic Oxidation (TAO) process to anaerobic digestate stabilization. In treating digestate with TAO reactor the internal temperature of the reactor was increasing higher and $51^{\circ}C$ and over was maintained after 6 days on. The physiochemical compositions of liquids increased from pH 8.1 to 9.8 and EC decreased from 29.8 to 12.0 mS/cm in treating process of digestate with TAO reactor. CODcr decreased from 22,654 to 18,843 mg/L, showed about 16.82% of remove efficiency. TN and $NH_4-N$ decreased from 4,813 to 1,733 mg/L, from 3,815 to 812 mg/L respectively, which showed about 64.0% and 78.7% of removal efficiency respectively.

• 산업경영시스템학회지
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• 제36권1호
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• pp.1-7
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• 2013

This study is aimed to investigate the association between anaerobic-aerobic exercise intensity and hand steadiness. Hand steadiness is the decisive contributor to affecting the job performance just as in the rifle shooting and archery in sports and the microscope-related jobs requiring hand steadiness in industries. In anaerobic exercise condition hand steadiness is measured through hand steadiness tester having 9 different diameter holes after each subject exerts 25%, 50%, 75%, and 100% of maximum back strength. In aerobic exercise occasion it is evaluated at each time heart rate reaches 115%, 130%, and 145% of reference heart rate measured in no task condition after they do jumping jack. The results indicate that an increased intensity in both types of exercise reduces hand steadiness, but hand steadiness at 25% of maximum back strength and 115% of reference heart rate is rather greater than at no exercise. Just as the relation between cognitive stress and job performance has upside-down U form, so does the association of physical loading to hand steadiness, which means that a little exercise tends to improve hand steadiness in comparison with no exercise.

• 한국환경과학회지
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• 제28권10호
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• pp.899-905
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• 2019

Recently, an innovative method for wastewater treatment and nutrient removal was developed by combining the sequence batch reactor and membrane bioreactor to overcome pollution caused by shipboard sewage. This system is a modified form of the activated sludge process and involves repeated cycles of mixing and aeration. In the present study, the bacterial diversity and dominant microbial community in this wastewater treatment system were studied using the MACROGEN next generation sequencing technique. A high diversity of bacteria was observed in anaerobic and aerobic bioreactors, with approximately 486 species. Microbial diversity and the presence of beneficial species are crucial for an effective biological shipboard wastewater treatment system. The Arcobacter genus was dominant in the anaerobic tank, which mainly contained Arcobacter lanthieri (8.24%), followed by Acinetobacter jahnsonii (5.81%). However, the dominant bacterial species in the aerobic bioreactor were Terrimonas lutea (7.24%) and Rubrivivax gelatinosus (4.95%).

• 청정기술
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• 제25권4호
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• pp.302-310
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• 2019

호기조와 혐기/무산소조를 직렬로 연결한 인공습지를 이용하여 크게 오염된 하천수를 처리하였다. 호기조는 자연 공기 배출 시스템을 통하여 공기가 연속적으로 공급되어 호기성 상태가 유지되었다. 인공습지의 성능에 영향을 미치는 최적의 영향인자를 조사하기 위하여 체류시간을 다르게 한 5개의 파일럿 플랜트를 사용하였다. 호기조에서 BOD (biochemical oxygen demand)와 COD (chemical oxygen demand)의 제거율은 1차 반응 속도식을 나타내었고, COD 제거 속도 상수는 BOD보다 약간 낮았다. 온도 의존성은 COD (θ = 1.0079)와 BOD (θ = 1.0083)제거에 대한 값이 거의 동일했으나 T-N 제거의 온도 의존성(θ_N)은 1.0189로 다소 높게 나타났다. SS제거율은 98%로 높았고 수력학적 부하 속도(Q/A)가 증가함에 따라 제거 효율이 증가하는 경향을 보였다. 혐기/무산소조에서 BOD와 COD 제거의 주요 메커니즘은 호기조와 완전히 다르게 나타났다. 혐기/무산소조에서 COD와 COD는 생물학적 탈질을 위한 탄소원으로 공급되었고 T-P는 혐기/무산소조 내의 orthophosphate와 자갈 사이의 양이온 교환에 의해 제거되는 것으로 조사되었다. 인공습지는 여과된 고형물에 의해 막힘 없이 성공적으로 운영되었고 고형물들은 매우 빠르게 연속적으로 분해되었다.

• 한국전문물리치료학회지
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• 제18권1호
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• pp.74-82
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• 2011

The purpose of this study was to compare the anaerobic threshold (AT) between subjects with and without non-specific chronic low back pain (NCLBP). The patient group included 15 women with NCLBP. The normal group included 15 women without NCLBP who were age-, height-, weight-, and activity level-matched. The subjects performed a Balke treadmill protocol which was symptom-limited progressive loading test. Their heart rate (HR), ventilatory gas and metabolic equivalents (METs) were measured using the automatic breath gas analyzing system. After the test, each subjects' ratings of perceived exertion (RPE) were evaluated. The visual analog scale (VAS) was assessed pre- and post-test. The independent t-test and Wilcoxon's signed-rank test were used for analysis of the data. Time, HR, the volume of oxygen consumption ($VO_2$), relative $VO_2$, and METs at the AT level of the patient group were significantly lower than those of the healthy group (p<.05). However, there were no significant differences in RPE, VAS, and breathing frequency at the AT level (p>.05). The findings of this study indicate that patients with NCLBP had a lower aerobic fitness than healthy subjects. Thus, implementation of rehabilitation program to increase aerobic fitness may be considered in patietns with NCLBP, and further studies are required to determine the etiological factors of decreased aerobic fitness.