• The Korean Journal of Physiology
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• 제2권2호
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• pp.1-10
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• 1968

Maximal oxygen consumption measurements were performed on 15 middle school boys (age: mean 14.0, range: $13{\sim}16$ years) and 14 high school boys (age: mean 17.4, range: $16{\sim}19$ years). General body build was greater in the high school boys and absolute values of body height, body weight, skinfold thicknesses, maximal oxygen uptake, and maximal pulmonary ventilation followed the same trend. Considered on the basis of body build, however, the values of high school boys were not always greater than those of middle school boys. The following results were obtained. 1. Maximal oxygen consumption in middle school boys was 2.11 l/min., 53.7ml/kg b. weight, 13.9 ml/cm body height, and 63.7 ml/kg LBM. In high school boys the values were: 2.86 l/min., 52.7 ml/kg b.wt., 17.5 ml/cm b. height, and 57.9 ml/kg LBM. Thus, middle school boys were superior to high school boys on body weight and lean body mass basis. They were also superior to the European boys of the same age. 2. The ratio of maximal oxygen uptake to resting value was 9.7 in middle school boys, and 10.8 in high school boys. 3. Maximal pulmonary ventilation in middle school boys was 58.0 l/min., and 84.0 l/min. in high school boys. The ratio of maximal ventilation to resting value was the same as oxygen uptake, namely, 9.7 in middle school boys and 10.7 in high school boys. 4. Ventilation equivalent in middle school boys was 27.5 and 29.3 in high school boys. These values represent values of untrained male subjects. 5. Maximal heart rate in high school boys reached to 193 beat/min. and is 2.9 times that of resting heart rate. 6. Maximal oxygen pulse in high school boys was 16.6 ml/beat and was same as that of untrained subject. 7. Correlation between body weight and maximal oxygen consumption in middle school boys was r=0.570, and r=0.162 in high school boys. Correlation between lean body mass in middle school boys was r=0.499, and r=0.158 in high school boys. Interrelation between body weight and maximal pulmonary ventilation was poor. 8. The differences between trained and untrained subjects were discussed.

• 한국산업보건학회지
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• 제31권1호
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• pp.60-72
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• 2021

Objectives: This study was performed to investigate the level of participation in and satisfaction with training courses at job training institutions and to improve participation and satisfaction through changes in the training method for industrial ventilation subjects. Methods: The results were analyzed for the mean and standard deviation by t-test and ANOVA, (p=0.05). Participation rates were examined for three courses: specialization, job training, and supervisory. The participation inthe education was 428 people, and the result of satisfaction with the change of education method was 878 people. Satisfaction was investigated for the specialized curriculum and job training curriculum,but not the supervisor curriculum. The satisfaction results for six items(contents, quality, skill, level, degree of understanding, degree of practical) were analyzed according to the change in the training medium and the method among people in one occupational ventilation subject. Results: The participation rate was similar in the job training and specialized training courses, but the lowest rate was in supervisory courses(p=0.05). In general, there was the lowest participation on the first day of education, and the participation rate improved after the second day. Satisfaction with the course was high for the specialized education course with a number of practical education assignments(p=0.278). The satisfaction level for the teaching method in the industrial ventilation subjects was high in a mixed group which combined lecture and practice. The industrial ventilation course in the basic job training course showed a difference between lecture and mixed education(p=0.111), but there was no significant difference. However, the industrial ventilation course in the advance job training course showed a clear difference between lecture and the mixed education(p=0.036). Conclusions: Therefore, the first day of training should start in the afternoon so that more trainees can participate, and it is recommended to assign important subjects after two days. In addition, it is suggested that job competency-enhancing education utilize various educational methods and media.

• 복식문화연구
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• 제29권6호
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• pp.747-762
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• 2021

The purpose of this study was to examine the current satisfaction levels with nurse uniforms at Taizhou General Hospital in China and to find areas for improvement in order to develop nurse uniforms with improved comfort, fit and convenience. To investigate satisfaction with nurse uniforms, a survey was conducted of 150 nurses. The general characteristics of the nurses, uniform conditions, feelings of satisfaction, fit, preferred designs, inconvenient aspects of the uniforms, and areas for improvement were analyzed. Eight materials of cotton/polyester blended fabrics were selected according to Chinese nurse uniform regulations, and the physical properties of the materials were tested along with the materials used in current nurse uniforms. Four new nurse uniforms with increased aesthetics, functionality, and comfort were developed based on the survey results. Materials with excellent absorption, moisture permeability, and ventilation were used as main fabrics. According to the preferred designs of nurses at Taizhou City General Hospital, China, 4 types of nurse uniforms designed, consisting of design 1 (shirt and pants), design 2 (shirt and pants), design 3 (dress), and design 4 (shirt and skirt). The new nurse uniforms offered better functionality with an improved fit at the armpits, waist, hips, and knees based on product measurements.

• 한국환경보건학회지
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• 제35권5호
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• pp.355-361
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• 2009

This study evaluated the bacterial concentrations and affecting factors at the laboratories of a university in Seoul, Korea. Thirty-three samples of total airborne bacteria (TAB) and eighteen samples of gram negative bacteria (GNB) were collected from both microbiology laboratories (7) and chemistry laboratories (6). GM (GSD) of TAB and GNB concentrations were 194 (2.52) $cfu/m^3$, 24 (4.1) $cfu/m^3$, respectively. TAB concentrations in the chemical laboratories (GM (GSD): 193 (2.0) $cfu/m^3$) were not significantly different from those in microbial laboratories (GM (GSD): 202 (2.7) $cfu/m^3$, (p>0.05)). GM (GSD) of TAB concentrationsat the top of sink, the center of laboratory, and the front of ventilation ventilation device within laboratories, 182 (3.2) $cfu/m^3$, 217 (2.2) $cfu/m^3$, 176 (2.4) $cfu/m^3$, respectively, were not significantly different (p=0.48). Related factors were measured such as temperature, relative humidity, floor of laboratory, number of persons and laboratory area. TAB concentrations were significantly related to temperature (r=0.36, p<0.05), and the floor of laboratory and temperature were also significantly related (r=0.49, p<0.001). However, other factors such as relative humidity, number of persons and laboratory area did not show any significant relationship with TAB concentrations (p>0.05). TAB concentrations were affected significantly by cleaning frequency (p<0.001) and floor of laboratory (p<0.05). There was also a significant difference (p<0.01) between TAB indoor concentrations and TAB outdoor concentrations. However, other factors such as general ventilation did not affect TAB concentrations (p>0.05) in this study.

• 한국축산시설환경학회지
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• 제6권1호
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• pp.1-14
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• 2000

The structural and environmental characteristics of typical pig houses in different growth phases were surveyed and analyzed. Based on the data for thirty nine selected farms in four provinces, Jeonbuk-do, Jeonnam-do, Gyeongbuk-do, and Gyeongnam-do, in the southern provinces, Korea, the goal is to eventually establish standard pig houses of sow and litter, nursery pigs, and growing-finishing pigs. The survey included farm scale, production specialization, structural dimensions of the houses and their ventilation systems, cooling and heating systems, and floor and pit systems related to manure collection. The survey showed 90∼98% of growing-finishing pig houses adopted the sidewall curtain systems. The sidewall curtain systems, although popular, is not well insulated which leads to excessive heating costs in winter. Regarding flooring and manure collection system of the house, 23∼35% of growing-finishing houses installed scraper systems with concrete-slat floors in Gyeongsang provinces while 52∼78% did in Jeolla provinces. The cause of a large variance in flooring between tow regions could not be academically pinpointed, rather it could be attributed to the advice of neighbors who leads local pig production circle. A general trend toward enlargement and enclosure of pig houses for all growth phases was gaining popularity in most regions in recent years. A steady shift to multisite operation from continuous operation was also observed to prevent a disease transfer. The structural design of a standard pig house with its environmental control systems including ventilation and heating/cooling system was suggested for further validation study. In-depth analysis of the survey data is presented in the Results and Discussion section.

• 한국축산시설환경학회지
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• 제5권1호
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• pp.1-15
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• 1999

The structural and environmental characteristics of typical pig houses in different growth phases were surveyed and analyzed. Based on the data for thirty six selected farms in four provinces, Gyonggi-do, Gangwon-do, Choongnam, and Chonbook, in Central Korea, the goal is to eventually establish standard pig houses of sow and litter, nursery pigs, and growing-finishing pigs. The survey included farm scale, production specialization, structural dimensions of the houses and their ventilation systems, cooling and heating systems, and floor and pit systems related to manure collection. The survey showed 90∼99% of growing-finishing curtain installation rate was lower by 10∼20%. The sidewall curtain system, although popular, is not well insulated which leads to excessive heating costs in winter. Regarding flooring and manure collection system of the house, there was quite a lot variability among provinces, with 30∼80% of the houses installing scraper systems with concrete-slat floors in comparison with 30∼60% using a slurry system. Gangwon-do and Choongbook Chungwoo-goon are the predominant regions that installed a scraper system. A general trend toward enlargement and enclosure of pig houses for all growth phases was gaining popularity in most regions in recent years. A steady shift to three site production from a lumped system was also observed to prevent a disease transfer. The structural design of a standard pig house with its environmental control systems including ventilation and heating/cooling system was suggested for further validation study. In-depth analysis of the survey data is presented in the Results and Discussing section.

• Clinical and Experimental Emergency Medicine
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• 제3권3호
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• pp.148-157
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• 2016

Objective Our aim was to compare the compression quality, exercise intensity, and energy expenditure in 5-minute single-rescuer cardiopulmonary resuscitation (CPR) using 15:1 or 30:2 compression-to-ventilation (C:V) ratios or chest compression only (CCO). Methods This was a randomized, crossover manikin study. Medical students were randomized to perform either type of CPR and do the others with intervals of at least 1 day. We measured compression quality, ratings of perceived exertion (RPE) score, heart rate, maximal oxygen uptake, and energy expenditure during CPR. Results Forty-seven students were recruited. Mean compression rates did not differ between the 3 groups. However, the mean percentage of adequate compressions in the CCO group was significantly lower than that of the 15:1 or 30:2 group ($31.2{\pm}30.3%$ vs. $55.1{\pm}37.5%$ vs. $54.0{\pm}36.9%$, respectively; P<0.001) and the difference occurred within the first minute. The RPE score in each minute and heart rate change in the CCO group was significantly higher than those of the C:V ratio groups. There was no significant difference in maximal oxygen uptake between the 3 groups. Energy expenditure in the CCO group was relatively lower than that of the 2 C:V ratio groups. Conclusion CPR using a 15:1 C:V ratio may provide a compression quality and exercise intensity comparable to those obtained using a 30:2 C:V ratio. An earlier decrease in compression quality and increase in RPE and heart rate could be produced by CCO CPR compared with 15:1 or 30:2 C:V ratios with relatively lower oxygen uptake and energy expenditure.

• Structural Engineering and Mechanics
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• 제70권4호
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• pp.479-497
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• 2019

In the current code design, the use of a uniform internal pressure coefficient of cooling towers as internal suction cannot reflect the 3D characteristics of flow field inside the tower body with different ventilation rate of shutters. Moreover, extreme weather such as heavy rain also has a direct impact on aerodynamic force on the internal surface and changes the turbulence effect of pulsating wind. In this study, the world's tallest cooling tower under construction, which stands 210m, is taken as the research object. The algorithm for two-way coupling between wind and rain is adopted. Simulation of wind field and raindrops is performed iteratively using continuous phase and discrete phase models, respectively, under the general principles of computational fluid dynamics (CFD). Firstly, the rule of influence of 9 combinations of wind speed and rainfall intensity on the volume of wind-driven rain, additional action force of raindrops and equivalent internal pressure coefficient of the tower body is analyzed. The combination of wind velocity and rainfall intensity that is most unfavorable to the cooling tower in terms of distribution of internal pressure coefficient is identified. On this basis, the wind/rain loads, distribution of aerodynamic force and working mechanism of internal pressures of the cooling tower under the most unfavorable working condition are compared between the four ventilation rates of shutters (0%, 15%, 30% and 100%). The results show that the amount of raindrops captured by the internal surface of the tower decreases as the wind velocity increases, and increases along with the rainfall intensity and ventilation rate of the shutters. The maximum value of rain-induced pressure coefficient is 0.013. The research findings lay the basis for determining the precise values of internal surface loads of cooling tower under extreme weather conditions.

• 한국가스학회지
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• 제26권6호
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• pp.65-75
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• 2022

최근 수전해설비의 운전압력이 증가함에 따라 수소 누출로 인한 화재 및 폭발 가능성 및 위험성 또한 증가하고 있다. 따라서 관계법령 및 기술기준에 따라 수전해 시스템에 설치되는 모든 전기기에 전기방폭 형식인증 제품을 사용하거나 적절한 방법에 따른 비폭발위험장소화 절차를 적용해야 한다. 본 연구에서는 수전해설비의 일반적인 운전조건을 고려하여 KS C IEC 60079-10-1 및 KGS GC101에 따른 폭발위험장소 구분 및 범위 산정을 수행하였다. 또한, 비폭발위험장소화를 달성하기 위해 임계농도인 폭발하한 25 % 미만의 농도를 유지하기 위한 적정 환기량을 검토하였다. 그 결과 자연환기만 적용할 경우에는 수전해설비가 폭발위험장소로 구분되고, 이를 강제환기를 통해 비폭발위험장소로 구분하기 위해서는 막대한 환기량이 필요함을 확인할 수 있었다.

• Journal of Veterinary Science
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• 제21권2호
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• pp.27.1-27.10
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• 2020

The efficacies of a supraglottic airway device (SGAD) and an endotracheal tube (ETT) in cats under general anesthesia with volume-controlled ventilation (VCV) were compared. Thirty healthy cats were randomly allocated for airway control using either an SGAD or an ETT. Five tidal volumes (6, 8, 10, 12, and 14 mL/kg) were randomly tested, and respiratory rates were adjusted to achieve a minute ventilation of 100 mL/kg/min. The dose of propofol necessary to insert the SGAD or ETT, the static respiratory pressure, leakage during VCV, and end tidal CO₂ (ETCO₂) were recorded. Dosages of propofol and static respiratory measurements for the SGAD and ETT groups were compared using a t-test. The distribution of leakages and hypercapnia (ETCO₂ > 45 mmHg) were compared using Fisher's exact test. A significance level of p < 0.05 was established. No significant difference in dose of propofol was observed between the SGAD and ETT groups (7.1 ± 1.0, 7.3 ± 1.7 mg/kg; p = 0.55). Static resistance pressure of the SGAD (22.0 ± 8.1 cmH₂O/L/sec) was significantly lower than that of the ETT (36.6 ± 12.9 cmH₂O/L/sec; p < 0.01). Of the 75 trials, leakage was more frequent when using an SGAD (8 events) than when using an ETT (1 event; p = 0.03). Hypercapnia occurred more frequently with SGAD (18 events) than with ETT (3 events; p < 0.01). Although intubation with an ETT is the gold standard in small animal anesthesia, the use of an SGAD can reduce airway resistance and the work of breathing. Nonetheless, SGAD had more dead space and the tidal volume for VCV needs adjustment.