• Journal of the Korea Safety Management & Science
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• v.15 no.4
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• pp.97-103
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• 2013

The purpose of this study was to verify the change in temperature humidity perspiration of fire suit when applying phased intensive exercises to fire fighter wearing fire suit. For this study, three male fire fighters took basic physical test and performed 10 minute phased intensive exercises -exercise intensity I (30%VO2max), exercise intensity II (45%VO2max), exercise intensity III (60%VO2max) based on maximum oxygen consumption (VO2max)- wearing fire suit (helmet, boots, air respirator) in treadmill and took a rest. The result of study shows that the temperature in the suit elevated during stabilization period after each exercise intensity, humidity elevated as exercise intensity increased, perspiration elevated as exercise intensity increased. This study indirectly ascertained the fire suit's physiological change in fire fighters during field activities.

• Journal of Korean Biological Nursing Science
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• v.11 no.1
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• pp.1-13
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• 2009

Purpose: This study was conducted to evaluate the effects of table tennis program on self efficacy, cardiopulmonary function, serum lipids, catalase activity in the physical disabilities. Method: Physical disabilities were allocated to one of two groups: control group (n=7), experiment group (n=8). The experiment group took table tennis program four times a week for 12 weeks. Self efficacy was measured by questionnaire. Serum lipid profiles, catalase and cardiopulmonary function were checked after the exercise program and compared with pre-exercise data. Result: Self efficacy was significantly higher in the table tennis group. Maximum oxygen consumption and forced vital capacity were significantly increased and heart rate at rest was decreased in the table tennis group. Total cholesterol and triglyceride were decreased in the table tennis group. There was no significant change in catalase activity between two groups. Conclusion: These results indicate that table tennis program has positive effects on the health of the physical disabilities by improving the self efficacy and cardiopulmonary function and serum cholesterol profile.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2012.05a
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• pp.300-303
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• 2012

Global warming has been a serious problem due to excessive emissions of carbon dioxide from the increase of energy consumption. The present study investigates an energy generation mechanism that does not produce carbon dioxide and oxides of nitrogen. A reaction mechanism including sodium borohydride and hydrogen peroxide has been introduced and as a result, thermal energy can be generated from combustion of hydrogen with oxygen. Sodium borohydride dissolved in water reacting with liquid hydrogen peroxide may reveal maximum adiabatic reaction temperature of 1795 K at a mixture ratio of 0.89.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.10 no.1
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• pp.31-37
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• 2005

To find out temporal variations of net photosynthetic rate (NPR) of intertidal flats, we measured oxygen microprofiles in sediments with oxygen microsensors 4 times from December 2003 to June 2004. The study areas were the intertidial flats in Janghwa-ri and Dongmak-ri, located on the southwestern and the southern parts of Ganghwa-gun, respectively, and in Incheon North Harbor where the content of organic matter was relatively high. During the investigation, oxygen penetration depths in the tidal flats of Janghwa-ri and Dongmak-ri were high in December (mean values of 4.0-4.1 mm). Thereafter, the oxygen penetration depths declined to mean values of 2.2-2.8 mm and 1.6-1.8 mm in the two tidal flats. Interestingly, the oxygen penetration depths in the Incheon North Harbor tidal flat showed a lower range $(0.8{\pm}0.3\;mm;\;mean{\pm}1SD)$ over the period. The maximum NPR in the Dongmak-ri tidal flat was found in March $(11.1{\pm}2.8\;mmol\;O_2\;m^{-2}\;h^{-1})$, and those In Janghwa-ri $(6.1{\pm}4.1\;mmol\;O_2\;m^{-2}\;h^{-1})$ and Incheon North Harbor $(6.4{\pm}1.4\;mmol\;O_2\;m^{-2}\;h^{-1})$ were observed in May. During the period when NPR was most active, the highest oxygen concentration was found at 0.1-0.5 mm depth below the surface sediment, and was on average 1.8-3.2 times higher than the air-saturated oxygen concentration in the overlying seawater. Although we took into account of low in situ light intensity $(400{\mu}Einst\;m^{-2}\;s^{-1})$ during the investigation in June, NPR in the 3 study areas decreased significantly to less than $0.2\;mmol\;O_2\;m^{-2}\;h^{-1})$. Thus, temporal variations of NPR were somewhat different among the tidal flats. Generally, benthic primary producers inhabiting in the uppermost 0.5 mm of the sediment showed a peak photosynthetic activity in the study areas in spring. This is the first domestic report on photosynthetic rates of benthic microflora in the tidal flats with oxygen microsensors, and the use of the microsensor can be widely applied to measurements of benthic primary production of a tidal flat and the oxygen consumption rate of surficial sediments.

• Tuberculosis and Respiratory Diseases
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• v.85 no.2
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• pp.137-146
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• 2022

Background: Farinelli breathing (FB) exercise is a typical breathing exercise used by singers. This study aimed to compare effects of FB exercise and diaphragmatic breathing (DB) exercise on respiratory function and symptoms in patients with chronic obstructive pulmonary disease (COPD). Methods: Sixteen patients aged 51-80 years with mild or moderate COPD were recruited for this study. They were divided into two groups: DB group (n=8) and FB group (n=8). Both groups received complete breathing exercise training five times per week for 8 weeks. Their respiratory functions, COPD symptoms, cytokine levels, and oxidative stress variables were analyzed during pre- and post-tests. Dependent variables were compared between pre- and post-tests using paired t-tests. An independent t-test was used to compare variables between the groups. Differences were considered significant at p<0.05. Results: The maximal expiratory pressure (MEP), maximum oxygen consumption (VO₂max), and COPD Assessment Test (CAT) scores changed significantly in the DB group after the 8-week intervention compared to those at pre-test, whereas force vital capacity, forced expiratory volume in the first second, maximum voluntary ventilation, maximal inspiratory pressure (MIP), MEP, VO₂max, CAT score, tumor necrosis factor-α, and malondialdehyde level changed significantly in the FB group at post-test compared to those at pre-test. Moreover, both MIP and MEP in the FB group were significantly higher than those in the DB group. Conclusion: FB exercise improved respiratory functions and COPD symptoms of patients with COPD. It might be an alternative breathing exercise in pulmonary rehabilitation programs for patients with COPD.

• Journal of Korean Tunnelling and Underground Space Association
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• v.12 no.4
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• pp.321-328
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• 2010

The study performed an actual fire experiment in order to propose the heat release rate of automobile that is the most basic architectural element for the fire safety design in a tunnel, whose importance has been recognized as the underground traffic tunnels are planned in Korean metropolitan cities. The heat release rate of a van is measured by the large scale calorimeter, in which the law of oxygen consumption is applied, and the fire expansion characteristics in a tunnel by placing two passenger cars nearby one another in the tunnel. As the results, the heat release rate of the van was revealed to be 5.9 MW, and carbon monoxide was emitted 482 ppm at a maximum. In case of two passenger car experiment for the fire expansion characteristics, the adjacent car was ignited about 3 minutes 30 seconds after the fire occurrence, and the complete fire was developed after 15 minutes. The maximum heat release was 9 MW. The results from the actual fire experiment can be an important input data for future quantitative analysis as well as an element applicable to a tunnel disaster preventive equipment design.

• Journal of Soil and Groundwater Environment
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• v.10 no.4
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• pp.45-53
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• 2005

The objective of this study is to evaluate the effects of changes in soil temperature on biodegradation rate of diesel compounds from a field pilot test using hot air injection process. Total remediation time was estimated from in-situ biodegradation rate and temperature for optimum biodegradation. All tests were conducted by measuring in-situ respiration rates every about 10 days on highly contaminated area where an accidental diesel release occurred. The applied remediation methods were hot air injection/extraction process to volatilize and extract diesel compounds followed by a bioremediation process to degrade residual diesels in soils. Oxygen consumption rate varied from 2.2 to 46.3%/day in the range of 26 to $60^{\circ}C$, and maximum $O_2$ consumption rate was observed at $32.0^{\circ}C$. Zero-order biodegradation rate estimated on the basis of oxygen consumption rates varied from 6.5 to 21.3 mg/kg-day, and the maximum biodegradation rate was observed at $32^{\circ}C$ as well. In other temperature range, the values were in the decreasing trend. The first-order kinetic constants (k) estimated from in-situ respiration rates measured periodically were 0.0027, 0.0013, and $0.0006d^{-1}$ at 32.8, 41.1, and $52.7^{\circ}C$, respectively. The estimated remediation time was from 2 to 9 years, provided that final TPH concentration in soils was set to 870 mg/kg.

• Korean Chemical Engineering Research
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• v.45 no.1
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• pp.73-80
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• 2007

This article aims to optimize the nitrogen removal of a sequencing batch reactor (SBR) through the use of the activated sludge model and iterative dynamic programming (IDP). Using a minimum batch time and a maximum nitrogen removal for minimum energy consumption, a performance index is developed on the basis of minimum area criteria for SBR optimization. Choosing area as the performance index makes the optimization problem simpler and a proper weighting in the performance index makes it possible to solve minimum time and energy problem of SBR simultaneously. The optimized results show that the optimal set-point of dissolved oxygen affects both the total batch time and total energy cost. For two different influent loadings, IDP-based SBR optimizations suggest each supervisory control of batch scheduling and set-point trajectory of dissolved oxygen (DO) concentration, and can save 20% of the total energy cost, while meeting the treatment requirements of COD and nitrogen. Moreover, it shows that the re-optimization of IDP within a batch can solve the modelling error problem due to the influent loading changes, or the process faults.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.12
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• pp.1298-1304
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• 2005

This study was performed to evaluate the characteristics of the competition between two electron acceptors, perchlorate and nitrate, with Citrobacter Amalonaticus strain JB101. In addition, the applicability of membrane bioreactor(MBR) for perchlorate removal was evaluated. The maximum growth rate of strain JB101 on perchlorate and nitrate are 0.27 and 0.58 $hr^{-1}$, and maximum substrate utilization rates were 35.1 mg $ClO_4^-/g$ protein-day and 45.6 mg $NO_3^-/g$ protein-day, respectively. Nitrate was a competitive inhibitor for perchlorate, and strain JB101 prefer nitrate to perchlorate as electron acceptor. Complete removal of perchlorate could be achieved up to the surface leading rate of 4.6 g $ClO_4^-/m^2-day$ with the MBR fed with 20 mg $ClO_4^-/L$(HCMBR). When 5 mg/L of nitrate was added to the same influent, perchlorate removal efficiency decreased to 96.5%, while nitrate was completely removed. For the MBR fed with 0.7 mg/L of perchlorate (LCMBR), the maximum perchlorate removal efficiency was 100% up to the loading rate of 0.23 g $ClO_4^-/m^2-day$. Membrane fouling was found to be a problem at high leading rate for both MBRs. The acetate consumption ratio per perchlorate was $13.7{\sim}51.7\;e^-eq./e^-eq.$ in LCMBR, while the value was $2.5{\sim}3.6\;e^-eq./e^-eq.$ in HCMBR. This difference could be related to the acetate consumption with oxygen as electron acceptor. Therefore, the amount of acetate addition must be determined considering the concentrations of other electron acceptors in the influent.

• Journal of Nutrition and Health
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• v.35 no.2
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• pp.223-228
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• 2002

The purpose of this study was to investigate the relationship between iron deficiency without anemia and physical performance in healthy women aged 20-21 yrs. Ten subjects with normal iron stores (serum ferritin $\geq$ 12$\mu\textrm{g}$/L: iron-sufficient group) and 11 subjects with iron depletion without anemia (serum ferritin < 12 $\mu\textrm{g}$/L and serum hemoglobin > 120 g/L: iron-depleted group) were chosen from a group of 50 women and were given physical-performance tests, including determinations of maximum oxygen consumption (VO$_2$ max) and ventilatory threshold. Iron status assessment included determination of hemoglobin, hematocrit, seam ferritin, total iron-binding rapacity, serum iron and transferrin saturation values. Dietary iron intake was assessed based on seven-day food intake records written by the subjects. Physical activity level was estimated by frequency questionnaires and two-week physical activity records were compiled daily by the subjects. Blood ferritin concentration was significantly lower in the iron-depleted group than in the iron-sufficient group (p < 0.05). However, other variables showing iron status was not different between the groups. There were no significant differences in body size, body composition and physical activity levels between the groups. Daily dietary iron, total protein and animal protein intakes of the iron-sufficient group were significantly higher than those of the iron depleted group. However, no differences were found in the amount of dietary vitamin C and fiber between the groups. The values for VO$_2$max and VO$_2$max corrected with weight or fat-free mass were not different between the groups. However, the ventilatory threshold was significantly higher in the iron sufficient group than in the iron-depleted group. The lower ventilatory threshold in the iron-depleted group suggests that iron depletion without anemia could diminish aerobic physical performance in young women. In addition, a significant correlation of physical performance to serum fferritin level was shown only in the iron depleted group.