• Proceedings of the Korean Environmental Health Society Conference
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• 2001.04a
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• pp.75-76
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• 2001

• Journal of Nutrition and Health
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• v.29 no.9
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• pp.1003-1012
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• 1996

We examined the relationship among riboflavin intake, work activity, erythrocyte glutathione reductase activity coefficient(EGR AC)and urinary riboflavin excretion. We also attempted to determine factors affecting seasonal riboflavin status of rural women. All information about nutrient intake, work activity and riboflavin biochemical status was repeatly collected in three seasons ; farming season(June), harvest season(October), nonfarming season(February). EGR AC was negatively correlated with riboflavin intake(P<0.005) and positively correlated with the duration(min) of farming activity(P<0.005) and the percentage of lean body mass(LBM) (%) representing long term physical activity(P<0.05) in harvestseason. Urinary riboflavin excretion was positively correlated with the ratio of riboflavin intake to 1,000kcal of energy expenditure (P<0.05) in farming season and negatively correlated with the duration(min) of farming activity (P<0.05) and crude nitrogen balance(P<0.005) in harvest season. It appeared that EGR AC seems to increase and urinary riboflavin excretion seems to decrease as work activity increase. Therefore work activity would be expected to deteriorate riboflavin status. Multiple regression analysis of variables showed that in general EGR AC was affected by riboflavin and energy intakes, energy expenditure, energy balance, the duration(min) of farming activity, LBM (%). Urinary riboflavin excretion was affected by riboflavin and protein intakes, LBM(kg) and crude nitrogen balance. Crude nitrogen balance affected urinary riboflavin excretion in all seasons. The result indicated that work activity as well as nutrient intake seemed to affect riboflavin status, especially EGR AC was affected preferentially be work activity in all seasons.

• Proceedings of the Korean Sanitation Conference
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• 2000.11a
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• pp.65-84
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• 2000

• Proceedings of the Korean Environmental Health Society Conference
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• 2004.12a
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• pp.74-74
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• 2004

• Journal of Environmental Science International
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• v.17 no.10
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• pp.1069-1073
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• 2008

Indoor air quality can be affected by indoor sources, ventilation, decay and outdoor levels. Although technologies exist to measure these factors, direct measurements are often difficult. The purpose of this study was to develop an alternative method to characterize indoor environmental factors by multiple indoor and outdoor measurements. Using a mass balance model and regression analysis, penetration factor (ventilation rate divided by the sum of ventilation rate and deposition constant) and source strength factor (source strength divided by the sum of ventilation rate and deposition constant) were calculated using multiple indoor and outdoor measurements. Subsequently, the ventilation rate and $NO_2$ generation rate were estimated. Mean of ventilation rate was 1.41 ACH in houses, assuming a residential N02 deposition constant of 0.94 $hr^{-1}$. Mean generation rate of $NO_2$ was 16.5 ppbv/hr. According to house characterization, inside smoking and family number were higher $NO_2$ generation rates, and apartment was higher than single-family house. In conclusion, indoor environmental factors were effectively characterized by this method using multiple indoor and outdoor measurements.

• Journal of Environmental Science International
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• v.19 no.3
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• pp.323-329
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• 2010

To acquire preliminary data for the control of total nitrogen (TN) in S sewage treatment plant, which processes merging food waste and sewage, the effect of reject water on the total nitrogen in the effluent was examined in this study. Water quality data for the plant during the winter period were applied to calculate the mass balance. It was calculated that at least more than 231 kg/d TN should be removed to control the TN concentration in the effluent. Assuming 18 ppm as the goal TN concentration in the effluent, about 941 kg/d TN should be removed from this plant. Approximately 10% more TN should be removed than at present to achieve this result. It was observed that dewatering the filtrate had a considerably greater effect on the total nitrogen in the effluent than the reject waters. The dewatered filtrate contained 1,399kg/d TN. The contribution of the dewatered filtrate to the TN concentration in the effluent was 0.183, which was 7 to 23 times greater than the other reject waters. In addition, the amount of total nitrogen from the reject water, with the exception of the dewatering filtrate, was lower than the amount of TN that should be removed from S sewage treatment plant. Therefore, it was concluded that one of the most effective methods for controlling the TN concentration in effluent was the removal of the TN contained in the dewatering filtrate.

• Journal of the Korea Organic Resources Recycling Association
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• v.29 no.1
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• pp.37-46
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• 2021

Nitrogen and phosphorus in livestock manure are environmental pollutants, but also could be valuable industrial resources. In the present study, we (1) introduced various nitrogen removal technologies such as stripping, thermal method, membrane, and electrodialysis, (2) reviewed relevant studies reported in 2011-2020, in particular, full-scale experiences, and (3) assessed each technologies based on the above survey results. In addition, we provided the information on the appropriate range of the pH, temperature, gas and liquid ratio, and so on in ammonia stripping process, and expected mass balance when it is connected to biogasification process. We hope the content herein can be helpful for making policy and operating full-scale plant in Korea.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.1B
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• pp.119-124
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• 2006

The purpose of this study was the comparison of pollutants removal and the track study of the nitrogen and phosphorus, the estimation of the nitrification and denitrification rate, and the investigation of the nitrogen mass balance between intermittently aerated membrane bioreactor(IAMBR) and intermittently aerated bioreactor(IABR), thus it verified the validity of the membrane submergence. As a result, it had no difference of organic matter removal, however, IAMBR showed better efficiency than IABR in the nutrients. Also, $NO_3{^-}$-N concentration at the anoxic state in the reactor was lower in IAMBR, and the denitrified nitrogen of IAMBR was 40.9%, that of IABR was 10.7%, thus it found out that the denitrification capability of IAMBR was higher than IABR above fourfold. Therefore, it seems resonable to conclude that the membrane helps to improve the removal of pollutants, because of the high MLSS concentration and the available method of intermittent inflow/outflow.

• Journal of environmental and Sanitary engineering
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• v.12 no.2
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• pp.1-12
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• 1997

This research aims to develop biofilm process for the nutrient removal of piggery wastewater. The developed process is the four stage anoxic-oxic biofilm process with recirculation of the final effluent. In summery, the results are as follows: 1. Nitrification in the piggery wastewater built up nitrite because of the high strength ammonia nitrogen. The nitrification of nitrobacter by free ammonia was inhibited in the total ammonia nitrogen loading rate with more than 0.2 kgNH$_{3}$-N/m$^{3}$·d. 2. The maximal total ammonia nitrogen removal rate was obtained at 22$\circ $C and without being affected by the loading rate. But total oxidized nitrogen production rate was largely affected by loading rate. 3. Autooxidation by the organic limit was a cause of the phosphorus release in the aerobic biofilm process. But the phosphorus removal rate was 90 percent less than the influent phosphorus volumetric loading rate of above 0.1 kgP/m$^{3}$·d. Therefore, the phosphorus removal necessarily accompanied the influent loading rate. 4. On the anoxic-oxic BF process, the total average COD mass balance was approximately 67.6 percent. Under this condition, the COD mass removal showed that the cell synthesis and metabolism in aerobic reactor was 42.8 percent and that the denitrification in anoxic reactor was 10.7 percent, respectively.

• Journal of Nutrition and Health
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• v.34 no.6
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• pp.637-644
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• 2001

The purpose of this study was to examine the effect of exercise and diet control program on nitrogen balance in obese children. The subjects of this study were five obese boys aged from 8 to 12 participating in the control period(C) for 3 days, exercise without energy deficit period(EEN) for one week, and exercise with energy deficit period(EED) far another one week, consecutively. The intensity of the exercise was 60-70% of HRmax and the energy was restricted at 493 kcal/day. Daily mean total energy intake was 2,152 $\pm$ 138kca1, 1,861 $\pm$ 138kca1, and 1,368 $\pm$ 87kca1 for the period C, EEN and EED, respectively. The body weight for EEN and EED decreased compared with the period C by average 1.2 $\pm$ 0.2kg and 1.8 $\pm$ 0.3kg, respectively. Of the body weight loss, the fat mass decreased bur 1.0 $\pm$ 0.3kg and 1.5 $\pm$ 0.5kg and the lean body mass by 0.2 $\pm$ 0.4kg and 0.3 $\pm$ 0.4kg, respectively. Of the daily mean nitrogen consumption was 9.1 $\pm$ 0.7g, 9.1 $\pm$ 0.8g and 7.1 $\pm$ 0.5g, the daily mean nitrogen excretion from feces was 1.3 $\pm$ 0.2g, 0.9 $\pm$ 0.1g and 0.7 $\pm$ 0.1g, and from urine was 6.7 $\pm$ 0.6g, 6.6 $\pm$ 0.5g and 6.7 $\pm$ 0.6g, for the period C, EEN and EED, respectively. Daily mean nitrogen balance excluding nitrogen excretion firm feces and urine indicated + 1.1 $\pm$ 1.0, +1.6 $\pm$ 0.6 and - 0.3 $\pm$ 0.9 for the period C, EEN and EED, respectively. Despite the negative indication during EED, there was no statistical signifiranre. The daily mean creatinine excretion was 0.5 $\pm$ 0.0g, 0.7 $\pm$ 0.1g and 0.6 $\pm$ 0.0g and the creatinine-height index(CHl) was 85.1 $\pm$ 6.7%, 83.8 $\pm$ 6.6% and 81.0 $\pm$ 6.5%, for the period C, EEN and EED, respectively, indicating little significant difference among the periods. Taking above results into consideration, it seems the exercise program conducted for this study did not substantially affect the nitrogen balance of the obese children, and may be used far the body weight control. Howeever, the adequacy of the energy restriction and amount of exercise applied to this study need to be further investigated as the nitrogen balance indicated negative and increasing tendency of the creatinine excretion showed during the EED compared with period C, despite the statistical insignificance.