• International Journal of Industrial Entomology and Biomaterials
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• v.23 no.2
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• pp.207-213
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• 2011

The diapause of $Telegryllus$ $emma$, the Emma field cricket, was investigated to study the ecological characteristics of the species. Changes in the volume, oxygen consumption, and water content of T. emma eggs were followed from oviposition. An increase in volume, oxygen consumption and water uptake occurred from 7 to 8 days following oviposition. The oxygen consumption of the eggs increased slowly for 7 days following oviposition, but then decreased until 15 days following oviposition. These results showed that a physiological change at diapause initiation affected the volume, water content, and oxygen consumption of the $T.$ $emma$ eggs. An experimental investigation of egg hatching showed that the eggs could be stocked at $10^{\circ}C$ for 40 days with a 14 day pre-period after laying and yield, 62.1% hatchability under these conditions. Maintaining the temperature at approximately $10^{\circ}C$ was favorable for hatching. Another experiment on egg hatching showed that the storage of eggs at $10^{\circ}C$ from 40 to 180 days would ensure satisfactory, hatching capacity.

• The Korean Journal of Physiology
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• v.1 no.1
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• pp.83-90
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• 1967

In order to evaluate the accuracy of the measurement of maximal oxygen intake (MOI), the MOI in seven subjects was determined 3 to 4 times in each individual. Following a 10 minute warm-up on treadmill (4.3 km/hr with 9 degree grade), the subject was asked to run at a speed of 8.73 km/hr on treadmill for a period of 3 minutes at a given grade which was elevated in a step-wise manner from zero to the level of exhaustion. Following a 3 minute run, the subject was allowed to rest for a period of 3 to 5 minutes. During each period of running, several cardio-pulmonary functions were determined and the range of variability for each measurement was computed. The oxygen consumption during the maximal work load was taken as the MOI. The results may be summarized as follows: (1) The minute volume, the oxygen consumption and the heart rate increased linearly until the grade was elevated to 9 degree above which these values were leveled off. (2) The minute volume and the heart rate during maximal exorcise were $87.4{\pm}8.10\;1/min\;and\;187{\pm}3.7$ per minute, respectively. (3) The maximal oxygen intake which corresponds to the oxygen consumption during maximal exercise was averaged to 3.04 1/min. (4) The coefficient of variance for the maximal oxygen intake was 6.32% while the corresponding values for the minute volume and the heart rate during maximal exercise were 5.22 and 2. 14%, respectively.

• Proceedings of the Korean Society of Life Science Conference
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• 2008.10a
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• pp.28.2-28.2
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• 2008

• The Korean Journal of Physiology
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• v.24 no.2
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• pp.249-260
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• 1990

Maximal cardiac output and oxygen uptake $(VO_{2max})$ were measured during treadmill exercise for seven top-class marathoners and nine non-athletes using impedance cardiograph developed by one of the authors (DW Kim). Results of this study are summarized as belows. 1) New shoes with sponge and silicon rubber attached to the soles were developed to reduce motion artifact during treadmill exercise. Ensemble everaging techneque with the developed shoes was also used to improve the measurement of stroke volume using impedance cardiography. 2) Maximal cardiac output of the athletes, 14.98 L/min, was significantly higher than that of the non-athletes, 13.46 L/min. As maximal heart rate of the marathoners is lower than that of non-athletes, stroke volume of the former is significantly larger than that of the latter. 3) $VO_{2max}$ of the marathoners, 59.38 ml/kg/min, was higher than that of the non-athletes, 40.22 ml/kg/min. At the anaerobic threshold. $VO_{2max}$ of the former was 62.3% of $VO_{2max}$ and this was significantly higher than that of the non-athletes, 57.2%, This results indicates that the marathoners have higher aerobic capacity than the non-athletes. 4) The marathoners showed larger $VO_2$ than the non-athletes at the same cardiac output, indicating that a-v $O_2$ of the former is higher than that of the latter. 5) Maximal systolic pressure of the marathoners was higher than that of the non-athletes, and so was maximal rate-pressure products. These results indicate that heart oxygen consumption rate $(hVO_2)$ of the marathoner is higher than that of the non-athletes is mainly due to higher stroke volume. And higher oxygen consumption of the marathoners is due to higher stroke volume. And higher oxygen consumption of the marathoners is due to their larger a-v $O_2$. The marathoners show both higher threshold and $VO_{2max}$. Especially, measurement of cardiac output during treadmill exercise by improved impedance cardiography is expected to contribute in study of cardiac function of athletes.

• Journal of the Korean Society of Safety
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• v.31 no.4
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• pp.55-63
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• 2016

A dust explosion is a phenomenon of strong blast wave propagation involving destruction which results from dust pyrolysis and rapid oxidation in a confined space. There has been some research done to find individual explosion characteristics and common physical laws for various dust types. However, there has been insufficient number of studies related to the heat of combustion of materials and the oxygen consumption energy about materials in respect of dust explosion characteristics. The present study focuses on the relationship between dust explosion characteristics of wood dust samples and oxygen consumption energy. Since it is difficult to estimate the weight of suspended dust participating in explosions in dust explosion and mixtures are in fuel-rich conditions concentrations with equivalent ratios exceeding 1, methods for estimating explosion overpressure by applying oxygen consumption energy based on unit volume air at standard atmospheric pressure and temperature are proposed. In this study an oxygen consumption energy model for dust explosion is developed, and by applying this model to TNT equivalent model, initial explosion efficiency was calculated by comparing the results of standardized dust explosion experiments.

• The Korean Journal of Food & Health Convergence
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• v.7 no.6
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• pp.17-24
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• 2021

This study investigates the exercise-physiological changes in stages through the movement of the automatic stepper and to analyze the usefulness of the automatic stepper. For 18 male university students, out of 10 levels, 5 level and 10 level of automatic stepper exercise were performed. At each 10, 20, 30 minutes during exercise, 5 and 10 minutes after exercise stop the subjects were examined to analyze the changes in energy consumption after minutes, respiratory exchange rate, heart rate, oxygen consumption per body weight, METs, cumulative energy consumption, and lactic acid to verify the usefulness of the automatic stepper. The mean and standard deviation were calculated using the SPSS, and one-way ANOVA with repeated measure was performed to verify the difference in the mean between time periods. The LSD method was used for the post-hoc test, and the significance level was set to α = .05. There were no significant changes in both 5 and 10 level, but the cumulative energy consumption over time increased significantly. In addition, as a low-intensity exercise intensity is shown, a low increase in lactic acid indicated a safe exercise level. In future studies, in-depth studies of various variables through regular exercise programs are needed for those who need safe exercise.

• Journal of Preventive Medicine and Public Health
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• v.17 no.1
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• pp.289-294
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• 1984

The energy expended while playing tennis was determined from the players heart rate and from the amount of oxygen they consumed. This study was made using eight healthy but unathletic male college students. Expired air was collected for 2 minute periods during each game by the Douglas bag method. Samples were collected when serving and receiving. The air collected was measured using a wet test gas meter. The amount of air collected was expressed in STPD. Oxygen consumption was determined by measuring the oxygen content of the expired air with a Orzat gas analyzer. The energy expended during the tennis games was calculated indirectly. The caloric coefficient of oxygen was multiplied by the volume of oxygen consumed. The caloric coefficient of oxygen varied from 4.6 to 5.1 kcal/liter of oxygen. In this study the value of 5 kcal/liter of oxygen was used in the calculations. The accuracy of the measurements of energy expended was tested using regression analysis of the measured volume of oxygen. The mean values of heart rate, oxygen consumed and energy expended did not vary when the activity of serving and receiving was compared. The mean value of oxygen consumed during play was $1.4329{\pm}282ml/min$ or $21.6{\pm}4.0ml/kg/min$. The energy expended was $7.15{\pm}1.46kcal/min$ or $6.45{\pm}1.23kcal/kg/min$. The values were equivalent to 5.5 mets. When the levels of oxygen consumed were estimated using the formulas, they were found to be higher than the measured levels. The estimated amounts, however, were within 25% of the measured amounts.

• The Korean Journal of Physiology
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• v.21 no.2
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• pp.305-311
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• 1987

To evaluate training effect, the step exercise was loaded to three mem for nine weeks. Step score, cardiopulmonary functions and blood constituents were measured before, during and after the test exercise (50 cm-step exercise and treadmill running), and were compared with the pre-tranining values. The results were as follows: 1) By the training, Harvard step score increased remarkably, expecially in the early stage of training. 2) The post-training values of maximal oxygen uptake increased very significantly and it seemed to be due to increases of stroke volume and tissue oxygen extraction. 3) After the training, the degree of increase in expired volume was small during the treadmill exercise. 4) By the training, increasing rate of respiratory quotient lessened during the exercise and it was considered to be caused by the decreases of carbohydrate consumption and anaerobic metabolism. 5) The blood cholesterol concentrations were harldy changed with this degree of training. 6) The blood lactate level decreased during the recovery periods and the values of the recovery 0 and 5 minutes decreased remarkably, in comparison with the pre-trained values. The above results suggest that the 9 week-training of the step exercise brings about the enhancement of circulatory functions and tissue oxygen utilization, and changes of food-stuffs used during the exercise.

• Korean Journal of Veterinary Research
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• v.11 no.2
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• pp.105-116
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• 1971

The effects of aconite root in rats and rabbits were studied following oral administration of the powder which was prepared by lyophilization of the decoction of the salted aconite roots. The $LD_{50}$ of the powder, the blood picture, total blood volume, uptake rate of ${42}^K$ and ${24}^Na$ in various organs, oxygen consumption, thyroid activity, and histopathological changes in various organs, were observed. The results obtained were as follows: 1. The $LD_{50}$ of the powder of decoction of the aconite root was 4.07g/kg of body weight in mice which is equivalent to approximately 40g/kg of the salted aconite roots. 2. The number of erythrocytes and leukocytes, hematocrit value, and the amount of hemoglobin in blood were increased in the rats administered daily dosages of 0.1, 0.5, and 1.0g/kg respectively. No significant differences were observed in the differential count of leukocytes. A slight tendency of hemoconcentration was recognized. 3. No changes in the erythrocyte volume, plasma volume and total blood volume were observed in the rats after administration of the powder for one, three, and six days. However, those were decreased in rats treated for ten days. 4. Generally, in various organs of rats the uptake rate of ${24}^Na$ showed a tendency of increasing but that of ${42}^K$ slowed a decreasing tendency. 5. The oxygen consumption was markedly decreased in rats administered the powder. 6. Iodine-131 uptake of thyroid gland was markedly decreased in the rabbits following administration of the powder. 7. In rabbits administered 0.5g/kg for 20 days, fatty changes of hepatic cells, cloudy swelling of the epithelial cells of proximal convoluted tubules of the kidney and the dilation of splenic sinuses were observed, however, milder changes were found in rabbits treated with 0.1g/kg for the same period.

• Journal of Biomedical Engineering Research
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• v.17 no.1
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• pp.43-48
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• 1996

We investigated the energistics of the physiological heart model by comparing predictive indexes of the myocardial oxygen consumption (MOC), such as tension-time index (R), tension-time or force-time inteual (FTI), rate-pressure product (RPP), pressure-work index, and systolic pressure-volume area (PVA) when using the electro-hydraulic left ventricular device (LVAD). We developed the model of LVAD incorporated the closed-loop cardiovascular system with a baroreceptor which can control heart rate and time-varying elastance of left and right ventricles. On considering the benefit of the LVAD, the effects of various operation modes, especially timing of assistance, were evaluated using this coupled computer model. Overall results of the computer simulation shows that our LVAD can unload the ischemic (less contractile) heart by decreasing the MU and increasing coronary flow. Because the pump ejection at the end diastolic phase of the natural heart may increase the afterload of the left ventricle, the control scheme of our LVAD must prohibit ejecting at this time. Since the increment of coronary flow is proportional to the peak aortic pressure after ventricle contraction, the LVAD must eject immediately following the closure of the aortic valve to increase oxygen availability.