• Title/Summary/Keyword: Ventilation capacity

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A numerical study on effects of drag coefficient of vehicle on jet fans in case of fire in road tunnels (도로터널 화재시 차량의 항력계수가 제연용 제연팬에 미치는 영향에 대한 해석적 연구)

  • Yoo, Yong-Ho;Yoo, Ji-Oh;Kim, Hyo Gyu
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.16 no.6
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    • pp.553-560
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    • 2014
  • The road tunnel install a vent for the purpose of ventilation and smoke control. Ventilation equipment capacity(number of jet fans) depends on from the condition that of the pressure and ventilation resistance. Pressure and the resistance under operating vehicle have affected on the drag coefficient. The drag coefficient of the tunnel have affected by the blockage effect and slipstream effects. However, when calculating the ventilation fan, are not properly consider taking into account such effects. Therefore, ventilation force may have been slightly overestimated. This paper describes the drag coefficient through a numerical analysis to calculate the equivalent resistance area that reflects the vehicle distance, and examined the equivalent resistance area. The ventilation coefficient corresponding to the result heavy vehicle mixing ratio of the present study was not clear. Equivalent resistance area had reduced by about 86% compared to the road design handbook current standards. Also it had analyzed and reduced to 62.2% compared to Korea Highway Corporation ventilation design criteria ratio, which is the old standard.

Survey on the Automation of Laying Hen Houses and Farmers' Awareness of its Significance (산란계농가의 자동화계사 시설실태 및 의식조사 연구)

  • Choe, Hui-Cheol;Seo, Ok-Seok;Lee, Deok-Su;Han, Jeong-Dae
    • Journal of Animal Environmental Science
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    • v.2 no.2
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    • pp.103-110
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    • 1996
  • This survey was conducted to investigate the situation of three types of laying hen houses and farmers' awareness of farm automation. Six windowless, three high-rising windowless and four open-sided laying hen houses were surveyed to compare their characteristics, and sixty farmers answered questionnaires. 1. Population density of laying hen was 13.9 birds/m^2$ in open-sided, 28.9 birds/m^2$ in high-rising windowless, and 44.9 birds/m^2$ in windowless laying hen houses. 2. Feeder space was $12{\sim}13.5cm$ in open-sided laying hen houses, but feeder space of windowless and high-rising hen houses was narrower than that of open-sided laying hen houses. 3. Thermal resistance values were $14.6{\sim}18.7\;m^2\;{\circ}C/W$ in wall, #22.0{\sim}23.7\;m^2\;{\circ}C/W$ in roof of windowless and high-rising windowless laying hen houses but the wall of open-sided laying hen houses was only $1.9\;m^2\;{\circ}C/W$. 4. Maximum ventilation capacity was 0.161{\sim}0.326$ cmm/bird in summer. Minimum rate of tunnel Ventilation laying hen houses in winter was $0.013{\sim}0.040$ cmm/bird, but minimum rate of crossflow and high-rising windowless laying hen houses was larger than that of tunnel ventilation houses. 5. One person managed about 8,100 birds in open-sided, and about 23,500 birds in windowless and high-rising windowless laying hen houses. 7. 90.7% of farmers responsed that they want to construct automatized laying hen houses in the future.

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Influence of Smokers's Jogging Exercises on Cardiopulmonary Function of Normal Adults in Their Twenties (20대 성인 흡연자의 조깅운동이 심장호흡기능에 미치는 영향)

  • Lee, Sam-Cheol
    • Journal of Korean Physical Therapy Science
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    • v.23 no.1
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    • pp.9-17
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    • 2016
  • Background and Purpose : Effects of smokers's jogging exercises on oxygen uptake, ventilation, heart rate, and vital-capacity of normal adults have not been studied in details on. In this study, people that had completed the established jogging exercises was selected for the study. We could examine the effects of imposed jogging in smokers who might be considered by an experienced physical therapist to be well practiced and proficient in this exercises. Subjects and Methods : A total number of 24 young healthy subjects participated in a randomized crossover controlled study and completed the study. The subjects of this study were divided into jogging and controlled groups which were composed 14 people respectively. The members of exercise group had jogging exercises 50 minutes a day, five times a week, for 5 weeks in same conditions, otherwise controlled group did not. Results : The results of this study were as follows. The jogging group demonstrated significant increases in cardiopulmonary function, vital-capacity and exercise capacity, compared with control group, which demonstrated no change in baseline measurements of 5 weeks. Conclusion : Jogging exercises can increase cardiopulmonary function in people after they have undergone successful PA. These results suggested that it was improved on cardiopulmonary function and lung capacity, since jogging exercise had. The results of this study could be applied for valuable criterion cardiopulmonary function. It is necessary to selects in various groups of the purpose of enhancing confidence in of this research.

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A study on the calculation method for the number of vehicles in queue to determine the fire ventilation capacity in road tunnels - forced on the effect of queue length (도로터널의 제연용량 산정을 위한 정체차량대수 산정기법에 관한 연구 - 정체길이를 중심으로)

  • Yoo, Yong-Ho;Kim, Hyo-Gyu;Ryu, Ji-Oh
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.18 no.1
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    • pp.41-52
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    • 2016
  • When the queue length of congestion vehicles in tunnel fire is extended beyond tunnel length, the capacity of smoke control system needs to be increased in line with ventilation resistance. However, the vehicle queue length is not defined, so a rational equation is necessary in current fire prevention guideline. This study is intended to propose an equation to calculate the queue length considering the number of vehicles in queue in tunnel fire and evaluate the applicability by tunnel length as well. When it comes to normal tunnel, it is necessary to compare the vehicle queue length with tunnel length up to the length of 1,200 m in a bid to avoid applying the vehicle queue length excessively in case of fire. As a result of evaluation of applicability to model a tunnel, saving the number of jet fan for smoke control appeared to be effective. Besides, quantitative approach to explain the vehicle queue length through the relationship between the percentage of large vehicles and tunnel length was presented. Consequently, when the queue length of the congestion vehicles exceeds the tunnel length in determining the capacity of smoke control system in case of fire, the number of vehicles beyond the tunnel length needs to be excluded from estimating the ventilation resistance by vehicles.

Application of Heat Balance Model Design of Ventilating and Cooling Greenhouse (온실의 환기 및 냉방 설계를 위한 열평형 모델의 작용)

  • 남상운
    • Journal of Bio-Environment Control
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    • v.9 no.4
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    • pp.201-206
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    • 2000
  • A certain system to overcome high temperature should be introduced for the stable year-round cultivation in greenhouses. There are efficient methods to overcome high temperature such as ventilation system with shading screen, fan and pad system with screen, and fog system with screen. This study was carried out to find a means to determine the capacity of such system. Heat balance equations for each system were established and verified by experimental results. The calculated ventilation rates from heat balance equations showed a good agreement with the measured ones. The evapotranspiration coefficient was the most important parameter affecting the ventilation requirement among input parameter affecting the ventilation requirement among input parameters except weather data. When the evaportanspiration coefficient increased 1%, the ventilation requirement decreased 1.3%. Therefore the data of evapotranspiration coefficient should be accumulated by various experiments, and then design standards and selection guidelines should be provided. The simulation results for same design conditions shown that air exchanges requirement and evaporating water of fan and pad system were 5.1∼7.7% and 6.8∼9.3% larger than those of fog system, respectively.

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Maximal Oxygen Uptake in the Secondary School Girls (여자 중 . 고등 학생의 최대 산소 섭취량)

  • Chung, Il-Dong;Nam, Kee-Yong
    • The Korean Journal of Physiology
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    • v.2 no.2
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    • pp.11-20
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    • 1968
  • Maximal oxygen uptake was measured in thirty-three secondary school girls by means of the treadmill test. Eighteen middle school girls aged 14.0 (range: $13.0{\sim}15.9$) years and fifteen high school girls aged 16.9 (range: $16.0{\sim}18.0$) years served as subjects. Maximal treadmill run lasted for 2 minutes and 20 seconds and the expired air was collected in a Douglas bag through a J-valve during the last one minute period. In general, absolute values of various measurements in the high school girls were greater than those of the middle school girls. When values were expressed on the body weight or lean body weight basis, however, work capacity of middle school girls was superior to that of the high school girls. The detailed results are as follows: 1. In middle school girls maximal oxygen uptake was 1.78 l/min., 47.4 ml/kg body weight, 12.3 ml/cm body height, and 61.7ml/kg lean body mass. In high school girls maximal oxygen uptake was 1.93 l/min., 39.7ml/kg body weight, 12.3 ml/cm body height, and 51.2 ml/kg LBM. Although the absolute value of maximal oxygen uptake was greater in high school girls than in middle school girls, values expressed on the body weight basis showed the reverse trend, namely, values of the middle school girls was greater than those of the high school girls. 2. The ratio of maximal to resting oxygen uptake was 8.8 in the middle school girls and was 10.2 in the high school girls. 3. Maximal pulmonary ventilation in the middle school girls was 55.3 l/min. and 66.1 l/min. in the high school girls. The ratio of maximal to resting pulmonary ventilation was 10.2 in the middle school girls and 10.1 in the high school girls. 4. The correlation between body weight and maximal oxygen uptake was relatively high, namely, r=0.79 both in middle and high school girls. The correlation coefficient between body weight and maximal pulmonary ventilation was a little less that of between maximal oxygen uptake and showed a value of r=0.60 both in middle and high school girls. The lean body mass was a poor reference of maximal oxygen uptake or maximal pulmonary ventilation as compared to body weight. The correlation between maximal oxygen uptake and maximal pulmonary ventilation was high and the coefficient of correlation in middle school girls was 0.927 and in high school girls it was 0.856. 5. Maximal ventilation equivalent was 30.9 liters in middle school girls and 33.9 liters in high school girls. This indicated that no hyperventilation was induced during the maximal of oxygen uptake exercise period as related to the maximal oxygen uptake. 6. Heart rate reached to the peak value within 1.5 minutes after beginning of maximal oxygen uptake run and remained at the same peak plateau level throughout the entire running period. Heart rate decreased steeply on cessation of running and subsided slowly thereafter. The maximal heart rate was 184 beat/min. in middle school girls and 189 beat/min. in high school girls. 7. Maximal oxygen pulse was 9.4 in middle school girls and 9.9 ml/beat in high school girls.

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Performance of Hygiene Management according to Capacity and Food Cost of Foodservice in Kindergartens (시설 규모 및 급식비에 따른 유치원 급식소 위생 관리 수행도)

  • Kim, Ok-Sun
    • Journal of the East Asian Society of Dietary Life
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    • v.24 no.5
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    • pp.680-690
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    • 2014
  • This study investigated the performance of hygiene management according to the capacity and food cost of foodservice in kindergartens as a measure of kindergartens foodservice hygiene management. Dietitians from the education office visited 50 kindergartens under the control of Dongbu District Office of Education during January, 2011. Kindergartens were 11 public and 39 private institutions. Over half of kindergartens (n=27) provided foodservice to 50~99 children. About 21 kindergartens had a foodservice cost per student per day of 2,000 won. Regarding personal hygiene, 'whether to wear an accessory or have a manicure' showed the best performance. 'Whether to have their health examined once every 6 months or keep their health records in 2 years' was rarely performed. For food materials, 'whether to buy food appropriate for the quality control standard of food materials' showed the highest performance. The highest performances for storage management of food materials and handling of food was 'whether to store goods within butlery at intervals more than 30 cm from the ground' and 'whether to heat and cook food more than $74^{\circ}C$', respectively. The highest performance for distribution of food and management of facilities was 'the hygienic management of cooking tools and facilities' and 'the proper installation of air-conditioning, heating and ventilation facilities', respectively. The results of this study show that capacity and food cost had the strongest effects on performance of personal hygiene. Especially, smaller facility size could increase performance of foodservice management.

Study on the Controlling Mechaniques of the Environmental Factors in the Mushroom Growing House in Chonnam Province (전남 지방에 있어서의 양송이 재배에 최적한 환경조건 조절법 분석에 관한 연구)

  • Chung, Byung-Jae;Lee, Eun-Chol
    • Journal of the Korean Wood Science and Technology
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    • v.2 no.2
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    • pp.32-34
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    • 1974
  • The important results which have been obtained in the investigation can be recapitulated as follows. 1. As demonstrated by the experimental results and analyses concerning their effects in the on-ground type mushroom house, the constructions in relation to the side wall and ceiling of the experimental house showed a sufficient heat insulation on effect to protect insides of the house from outside climatic conditions. 2. As the effect on the solar type experimental mushroom house which was constructed in a half basement has been shown by the experimental results and analyses, it has been proved to be effective for making use of solar heat. However there were found two problems to be improved for putting solar house to practical use in the farm mushroom growing: (1) the construction of the roof and ceiling should be the same as for the on ground type house, and (2) the solar heat generating system should be reconstructed properly. 3. Among several ventilation systems which have been studied in the experiments, the underground earthen pipe and ceiling ventilation, and vertical side wall and ceiling ventilation systems have been proved to be most effective for natural ventilation. 4. The experimental results have shown that ventilation systems such as the vertical side wall and underground ventilation systems are suitable to put to practical use as natural ventilation systems for farm mushroom house. These ventilation systems can remarkably improve the temperature of fresh air which is introduced into the house by heat transfers within the ventilation passages, so as to approach to the desired temperature of the house without any cooling or heating operation. For example, if it is assuming that X is the outside temperature and Y is the amount of temperature adjustment made by the influence of the ventilation system, the relationships that exist between X and Y can be expressed by the following regression lines. Underground iron pipe ventilation system. Y=0.9X-12.8 Underground earthen pipe ventilation system. Y=0.96X-15.11 Vertical side wall ventilation system. Y=0.94X-17.57 5. The experimental results have 8hown that the relationships existing between the admitted and expelled air and the $CO_2$ concentration can be described with experimental regression lines or an exponent equation as follows: 5.1 If it is assumed that X is an air speed cm/sec. and Y is an expelled air speed in cm/sec. in a natural ventilation system, since the Y is a function of the X, the relationships that exist between X and Y can be expressed by the regression lines shown below: 5.2 If it IS assumed that X is an admitted volume of air in $m^3$/hr. and Y is an expelled volume of air in $m^3$/hr. in a natural ventilation system, since the Y is a function of the X, the relationships that exist between X and Y can be expressed by the regression lines shown below. 5.3 If it is assumed that expelled air speed in emisec. and replacement air speed in cm/sec. at the bed surface in a natural ventilation system are shown as X and Y. respectively, since the Y is a function of the X. the relationships that exist between X and Y can be expressed by the following regression line: GE(100%)-CV (50%) ventilation system. Y=-0.54X+0.84 5.4 If it is assumed that the replacement air speed in cm/sec. at the bed surface is shown as X, and $CO_2$ concentration which is expressed by multiplying 1000 times the actual value of $CO_2$ % is shown as Y, in a natural ventilation system, since the Y is a function of the X, the relationships that exist between X and Y can be expressed by the following regression line: GE(100%)-CV(50%) ventilation system. Y=114.53-6.42X 5.5 If it is assumed that the expelled volume of air is shown as X and the $CO_2$ concencration which is expressed by multiplying 1000 times the actual of $CO_2$% is shown as Y in a natural ventilation system, since the Y is a function of the X, the relationships that exist between X and Y can be expressed by the following exponent equation: GE(100%)-CV(50%) ventilation system. Y=$127.18{\times}1.0093^{-x}$ 5.6 The experimental results have shown that the ratios of the cross sectional area of the GE and CV vent to the total cubic capacity of the house, required for providing an adequate amount of air in a natural ventilation system, can be estimated as follows: GE(admitting vent of the underground ventilation) 0.3-0.5% (controllable) CV(expelling vent of the ceiling ventilation) 0.8-1.0% (controllable) 6. Among several heating devices which were studied in the experiments, the hot-water boilor which wasmodified to be fitted both as hot-water boiler and as a pressureless steam-water was found most suitable for farm mushroom growing.

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Effect of the Balance Exercise on the Unstable Surfaces for the Vital Capacity in Healthy Adults: A Preliminary Study (불안정한 지지면에서의 균형운동이 건강한 성인의 폐활량에 미치는 효과: 사전 연구)

  • Kim, Taeho;Park, Hankyu
    • Journal of The Korean Society of Integrative Medicine
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    • v.4 no.3
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    • pp.17-25
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    • 2016
  • Purpose : This study attempts to examine the effect of the balance exercise on the unstable surfaces for the vital capacity in healthy adults. Methods : A total of 13 subjects was randomly divided into a breathing exercise training group (n=7) and a breathing and balance exercise training group (n=6). Changes in vital capacity and respiratory muscle activity were measured before and after the intervention. The intervention was performed three times a week for four weeks. Forced vital capacity (FVC), forced expiratory volume at one second (FEV1) and maximal voluntary ventilation (MVV) were used as measurement tools for the vital capacity test. Electromyography (EMG) was also used to examine respiratory muscle activity. Result : The breathing exercise training group showed significant improvement in terms of FVC, FEV1 and external oblique (EO), and transverse abdominis/internal oblique (TrA/IO) of MVV. The breathing and balance exercise training group showed significant improvement in terms of FVC, MVV and EO, TrA/IO of FVC and rectus abdominis (RA), EO, and TrA/IO of MVV. However, in comparing changes in vital capacity and respiratory muscle activity before and after the training, the breathing exercise training group and the breathing and balance exercise training group showed a significant difference in terms of MVV. Conclusion : This study is as a preliminary study to find out the relation between a balance exercise and a vital capacity, it is considered to require a further study with several revisions of subjects, duration and time for an intervention.

Significance Evaluation of Lung Volume and Pulmonary Dysfunction (폐용적과 폐기능 환기장애에 대한 유의성 평가)

  • Ji-Yul Kim;Soo-Young Ye
    • Journal of the Korean Society of Radiology
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    • v.17 no.5
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    • pp.767-773
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    • 2023
  • To In this study, we sought to evaluate related factors affecting lung volume and their significance in pulmonary function and ventilation disorders. As experimental subjects, 206 normal adult men and women who underwent a low-dose chest CT scan and a spirometry test were selected at the same time. The experimental method was to measure lung volume using lung CT images obtained through a low-dose chest CT scan using deep learning-based AVIEW. Measurements were made using the LCS automatic diagnosis program. In addition, the results of measuring lung function were obtained using a spirometer, and gender and BMI were selected as related factors that affect lung volume, and significance was evaluated through an independent sample T-test with lung volume. As a result of the experiment, it was confirmed that in evaluating lung volume according to gender, all lung volumes of men were larger than all lung volumes of women. he result of an independent samples T-test using the respective average values for gender and lung volume showed that all lung volumes were larger in men than in women, which was significant (p<0.001). And in the evaluation of lung volume according to BMI index, it was confirmed that all lung volumes of adults with a BMI index of 24 or higher were larger than all lung volumes of adults with a BMI index of less than 24. However, the independent samples T-test using the respective average values for BMI index and lung volume did not show a significant result that all lung volumes were larger in BMI index 24 or higher than in BMI index less than 24 (p<0.055). In the evaluation of lung volume according to the presence or absence of pulmonary ventilation impairment, it was confirmed that all lung volumes of adults with normal pulmonary function ventilation were larger than all lung volumes of adults with pulmonary ventilation impairment. And as a result of the independent sample T-test using the respective average values for the presence or absence of pulmonary ventilation disorder and lung volume, the result was significant that all lung volumes were larger in adults with normal pulmonary function ventilation than in adults with pulmonary function ventilation disorder (p <0.001). Lung volume and spirometry test results are the most important indicators in evaluating lung health, and using these two indicators together to evaluate lung function is the most accurate evaluation method. Therefore, it is expected that this study will be used as basic data by presenting the average lung volume for adults with normal ventilation and adults with impaired lung function and ventilation in similar future studies on lung volume and vital capacity testing.