• Journal of Korean Society of Water and Wastewater
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• v.27 no.6
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• pp.815-826
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• 2013

Using a developed mathematical model and calibrated kinetic constants, numerical experiments for a aerobic digestion of wastewater sludge by SBR aerobic digestion process combined with ultrasonication (USSBR) were performed in this study. It simulated well the phenomena of the decomposition of particulate organics and the release of organic nitrogen and transformation. To achieve 40 % of particulate organics removal, USSBR process requires only 6 days of SRT and 14 W/L of ultrasonic power whereas SBR aerobic digestion process requires 12 days of SRT. Based on the model simulation results, an empirical equation was presented here. This equation will be used to predict digestion efficiency for the given variables of SRT and ultrasonic power dose. USSBR aerobic digestion process can reduce the nitrogen concentration. The optimal operation strategy for the simultaneous removal of solids and soluble nitrogen in this process is estimated to 7 days of SRT with 14 W/L of ultrasonic power dose while anoxic period was 6 hours out of 24 hours of cycle time. In this condition, 40 % of particulate organics as well as 36 % of total nitrogen will be removed and the soluble nitrogen concentration of the centrate will be lower less then 40 mg/L.

• Journal of The Korean Society of Integrative Medicine
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• v.6 no.2
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• pp.117-123
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• 2018

Purpose : The purpose of this study was to investigate the effect of increased brain activity on the muscle endurance and the effect of brain activation through the combination of transcranial direct current stimulation and aerobic exercise on elderly woman. Methods : To investigate the effect of the muscle endurance on right leg, muscle endurance was evaluated by measuring the surface EMG of the muscles of the rectus femoris, biceps femoris, tibialis anterior, and gastrocnemius muscle. Results : There was a significant difference in the pre and post comparisons of muscle endurance on rectus femoris, biceps femoris, tibialis anterior muscle (p<.05). Difference of Combination of transcranial direct current stimulation and aerobic exercise group median frequency was smaller than control group (p<.05). There was not a significant difference in the pre and post comparisons of muscle endurance on biceps femoris, and gastrocnemius muscle. Difference of Combination of transcranial direct current stimulation and aerobic exercise group median frequency was showed a similar pattern. Conclusion : Through these results, It was found that increasing the brain activity by the transcranial direct current stimulation improves the exercise capacity on the elderly women. Combination of transcranial direct current stimulation and aerobic exercise maybe applied as an effective treatment for improving muscular endurance.

• Food Science and Preservation
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• v.18 no.1
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• pp.98-102
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• 2011

We evaluated microbial inactivation in chicken cage litter, to ensure microbial safety, using aqueous chloride dioxide. Contamination by coliforms, Escherichia coli, Listeria spp., yeasts and molds, total aerobic bacteria, and Salmonella spp. was detected in fresh cage litter, and microbial populations increased if litters were repeatedly used. Aqueous $ClO_2$ treatment (500 ppm) significantly decreased the populations of coliforms, E. coli, Listeria spp., yeasts and molds, total aerobic bacteria, and Salmonella spp. in all litter samples tested. In particular, aqueous $ClO_2$ treatment on fresh litter reduced the initial populations of coliform, E. coli, Listeria spp., yeasts and molds, and total aerobic bacteria by 4.47, 1.29, 1.23, 3.24, and 5.2 log CFU/g, respectively. In addition, when litters used for 1 and 5 weeks were tested, treatment significantly reduced microbial populations. The results suggest that aqueous $ClO_2$ treatment is useful to reduce microbial hazards in chicken cage litter and to improve the microbial safety of slaughtered chickens.

• Animal Bioscience
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• v.35 no.12
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• pp.1871-1880
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• 2022

Objective: The primary goal was to identify the effectiveness of chemical or biological additives in delaying the deterioration of early-harvested wilted rye silage after exposure to air. Methods: Rye harvested as a whole plant at the early heading stage was wilted for 24 h. The wilted forage was divided into treatments including sodium diacetate (SDA) at 3 (SDA3) and 6 g/kg (SDA6), Lactobacillus plantarum (LP), L. buchneri (LB), or their equal mixture (LP+LB) at 1×10⁶ colony-forming unit/g fresh matter. Results: After 60 d of conservation in 20-L silos, lactic acid was greater in LP and LP+LB silages than other treatments (102 vs 90.2 g/kg dry matter [DM]). Acetic acid was greatest in SDA6 (32.0 g/kg DM) followed by LB (26.1 g/kg DM) and was lowest in LP treatment (4.73 g/kg DM). Silage pH was lower with microbial inoculation and the lowest and highest values were observed in LP and untreated silages, respectively. After 60 d, neutral detergent fiber concentration was lowest in SDA6 silages, resulting in the greatest in vitro DM digestibility (846 g/kg DM). Aerobic stability was longest in SDA6 (176 h) followed by LB treatment (134 h). Instability after aerobiosis was greatest in LP silages (68 h), about 8 h less than untreated silages. After aerobic exposure, yeast and mold numbers were lowest in SDA6 silages, resulting in DM loss minimization. Exhaustion of acetic acid and lactic acid after aerobic exposure was lowest with SDA6 but greatest with untreated and LP silages. Conclusion: Treatment of early-cut wilted rye forage with SDA at 6 g/kg resulted in silages with higher feeding value and fermentation quality, and substantially delayed deterioration after aerobic exposure, potentially qualifying SDA at this load for promotion of silage quality and delaying aerobic spoilage of early-harvested (low DM) rye forage.

• Journal of Animal Environmental Science
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• v.5 no.2
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• pp.123-132
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• 1999

This study was carried out to find deodorization management method of the efflux from swine slurry treated by thermophilic aerobic oxidation reactor. Three kinds of deodorization methods in Lab-scale reactors, were used in this experiment; No treatment, air injection treatment(50$m\ell$ air/min. $\ell$) and inoculumn of photrophic bacteria treatement(108 cell(Most probable number, MPN)/$m\ell$). The concentration of volatile fatty acids(VFAs), hydrogen sulfide(H2S), and ammonia(NH3) were analyzed during the treatment period(50 days). The major results obtained as follows. 1. Air injection method to efflux showed very high removal effect on malodorants such as VFAs, hydrogen sulfide(H2B). But ammonia(NH3) was emitted to much. 2. PTB inoculum method was also effective in removal of malodorants, VFAs, Hydrogen sulfide(H2S), when it was applied to the efflux. 3. We found that the concentrations of malodorants, VFAs, H2S, NH3 had some relatinships with the pH, ORP, BOD in the efflux.

• Journal of Environmental Health Sciences
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• v.27 no.3
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• pp.11-20
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• 2001

An anaerobic sludge-aerobic fixed-bed biofilm(packed with ceramic support carrier of 1 inch size) reactor system was built up to treat textile wastewater. The efficiency of reactor system was examined by determining the effects of textile wastewater ratio(from 25% to 100% at HRT 24 h). The influent range of SCOD concentration and color were 1,036~1,357 mg/L, and 1,487~1,853 degree, respectively. When textile wastewater ratio was 100% and hydraulic retention time was 24 hours, SCOD removal efficiency by the anaerobic stage were 39.2% 100% and hydraulic retention time was 24 hours, SCOD removal efficiency by the anaerobic stage were 39.2% and the removal efficiency of the whole system were 75.8%. Color removal efficiency by the anaerobic stage were 45.4%(soluble color), and the removal efficiency of the whole system were 70.2%. In the A/A reactor system, the aerobic stage played an important role in removing both color and COD as well as anaerobic stage.

• Journal of Korean Society on Water Environment
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• v.23 no.6
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• pp.906-912
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• 2007

A lab-scale thermophilic aerobic digestion (TAD) system was operated at $64^{\circ}C$ with mixed primary and secondary sludges taken from a large wastewater treatment plant. The semi-continuously operated reactor at HRTs of 1, 3 and 6 days indicated that longer HRT could stabilize sludge organics and solids comparable to anaerobic digestion. It has been found that reduced HRT of 3 and 1 day produced the effluent with highly biodegradable soluble organics, indicating the possibility of energy recovery in TAD. No proof of biological nitrification was observed at thermophilic operating temperature of $64^{\circ}C$, while nitrogen removal seemed due to nitrogen exertion during the aerobic thermophilic cell synthesis as well as ammonia stripping.

• Journal of Korean Society on Water Environment
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• v.22 no.2
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• pp.333-341
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• 2006

The concept for the decolorization in biological dye wastewater treatment systems is based on anaerobic treatment, for the reductive cleavage of the dyes' azo linkages, in combination with aerobic treatment, for the degradation of the products from azo dye cleavage, aromatic amines. Batch tests were conducted to examine the conditions and the factors affecting biological treatment of dye wastewater. From the tests, the removal efficiencies of organics and colors of dyeing wastewater were improved to $COD_{Cr}$ 27% and color 9% by injecting 10% of the domestic wastewater as a cosubstrate, and $COD_{Cr}$ 30%, color 22% with 30% injection of domestic wastewater. Therefore it was proved that decolorization efficiency is demonstrated with domestic wastewater as a cosubstrate. The analysis of aromatic amines in wastewater showed that decolorization was achieved by cometabolism while aromatic amines were produced by cleavage of azo bonds under anaerobic conditions and these products were removed in an aerobic tank subsequently.

• Journal of Environmental Science International
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• v.28 no.10
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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%).

• Korean Journal of Environmental Agriculture
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• v.25 no.3
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• pp.202-210
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• 2006

To develop small-scale sewage treatment apparatus for detached house of agricultural village, a small-scale sewage treatment apparatus by natural purification method that consisted of packaged form of aerobic, anoxic and anaerobic bed was constructed. The efficiency of sewage treatment according to the sewage treatment method, sewage loading, and the injection method of sewage were investigated for small-scale sewage treatment apparatus of packaged form of aerobic, anoxic and anaerobic bed. The removal rate of pollutants according to the sewage treatment method for small-scale sewage treatment apparatus was high in the order of aerobic-anoxic-anoxic bed < aerobic-anoxic-anaerobic bed. The optimum filter media in small-scale sewage treatment apparatus was a broken stone. The removal rate of pollutants according to sewage loading in small-scale sewage treatment apparatus was high in the order of $1,200L/m^2{\cdot}day\fallingdotseq900L/m^2{\cdot}day\fallingdotseq600L/m^2{\cdot}day$. The removal rate of pollutants according to injection method of sewage in small-scale sewage treatment apparatus was high in the order of continuous injection $\fallingdotseq$ intermittent injection. When loaded under the optimum conditions, removal rate of BOD, COD, SS, T-N and T-P were 99, 95, 99, 83 and 96%, respectively, through this 3-stepped small-scale treatment apparatus arrayed with the order of aerobic, anoxic and anaerobic bed.