• Journal of the Korean Society of Safety
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• v.27 no.3
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• pp.89-95
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• 2012

The concentrations of Volatile Organic Compounds(VOCs) and Formaldehyde(HCHO) for interior materials of new vehicles are estimated and recognized by using the simulation program known as IAQx. The concentrations of contaminants are estimated and evaluated by the ventilation rates of new domestic vehicles and the required ventilation rates for new vehicles are estimated through the given contaminant data. This study is conducted to compare the ventilation rates for the contaminants between the discontinuously ventilated new vehicles and the continuously ventilated new vehicles using the simulation program. The equation of ventilation rate of new vehicles is acquired to be able to lower initial concentrations below the standard level under different conditions for both business and personal commuting.

• Advances in Energy Research
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• v.5 no.4
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• pp.277-287
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• 2017

This study examines the risk of overheating of a school building, under extreme hot weather conditions, in 14 locations in the United Kingdom using the overheating criteria defined in Building Bulletin 101 (BB101). The building was modelled as naturally ventilated, mechanically ventilated and in mixed mode and was simulated both for the current and the projected weather conditions of the 2050s. Under the current weather conditions, results of the simulations show that when naturally ventilated, the school building fulfils the BB101 criteria only in the areas of Edinburgh and Glasgow. In the simulations of the building as mechanically ventilated and in mixed mode, mechanical cooling was provided in order for the building to comply with the overheating criteria. A comparison of the required cooling loads between the two scenarios shows that application of mixed mode ventilation results in less cooling loads.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.22 no.2
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• pp.133-136
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• 2011

Background and Objectives : Previous jet ventilation is not becoming more common because of high price, making loud noise, and causing a movement of the vocal cords due to the jet stream. So we designed a new type of manually controlled jet ventilation using previous laryngoscope and introduced it's clinical application. Materials and Method : A prospective study involved 20 patients all having undergone surgical intervention under new type of manually controlled jet ventilation from June 2009 to January 2011. The prospective study was to assess the vital sign and operative and postoperative complications. Results : The Manually Controlled Jet Ventilation were performed in 20 patients. 50% of the patients have Post-located laryngeal lesion, 20% with tracheal stenosis, 20% with glottic cancer biopsy and laser cordectomy, 10% with postglottic stenosis. Conclusion : Manually Controlled Jet Ventilation (Manujet) can be used for airway surgery.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.28 no.2
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• pp.222-229
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• 2018

Objectives: The aim of this study was to evaluate gas concentrations such as oxygen in ginger storage tunnels, which are the causes of asphyxiation in confined spaces and suggest directions for safety and health management at ginger farms. Methods: Five farms in the Seosan and Taean areas which use underground ginger storage tunnels were chosen and examined with a walk-through survey and direct reading device for oxygen, hydrogen sulfide, ammonia, and carbon monoxide. Results: The oxygen concentration in the storage tunnels with no ventilation was found to be under 18% in summer, which may cause health effects. The concentration in those with ventilation was about 19%. The difference in temperature by measurement day had little effect on the concentration of oxygen. Conclusions: Even though some of farms had used compulsory ventilation systems, none of the farms visited possessed any direct reading device for oxygen. Warning systems using a direct reading device can be more effective, helpful, and required compared to ventilation, considering the difficulty and expense of periodical maintenance of ventilation systems and the fact that a farmer can be placed in danger when unaware of the malfunction of the ventilation system. In addition, a warning system may make farmers more cognitive of agricultural safety and health actions while a ventilation system can cause them to become passive and ignorant of workplace hazards.

• Environmental Engineering Research
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• v.22 no.2
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• pp.216-223
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• 2017

For the prediction of the ventilation rate for removing the non-isothermal concentrated fume from the semi-enclosed space, the computational fluid dynamics (CFD) analysis was done. Securing the proper ventilation conditions in emergency state such as in fire is crucial factor for the protection of the resident in the space. In the analysis for the determining the proper ventilation rate, the experimental study had the limitation for simulating the versatile conditions of fume development. The theoretical and computational method had been chosen as the alternate tool for the experimental analysis. In this study, the CFD analysis was done on the defined model which already had been done the experimental analysis by the previous workers. By comparing the prediction on the plume heights and the ventilation rates by the CFD analysis at, and in the parametric model of $1m^3$ with those of the previous experimental works, the feasibility of the computational analysis was evaluated. For the required ventilation rate analyzed by the CFD analysis was over predicted in 7.1% difference with that of the experimental results depending on the different plume height. With the comparison with the analytical Zukoski model at, the CFD analysis on the ventilation was under predicted in 8.3%. By the verification of the feasibility of the CFD analysis, the extended analysis was done for getting the extra information such as the water vapor distribution and $CO^2$ distribution in the semi-enclosed spaces.

• Journal of the Korean housing association
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• v.15 no.3
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• pp.101-108
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• 2004

To find more efficient exhaust effect, air curtain of upward or downward trend in gas table and left or right side of range hood were made. As result that film vapor from range hood lower part by digital camera, the air current change by moving existence and nonexistence of exhaust fan and direction of air curtain were known. Under all experiment condition, upward air curtain superior exhaust performance.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.12
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• pp.1767-1773
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• 2015

Effects of water-misting sprays with forced ventilation after transport during summer on meat quality, stress parameters, glycolytic potential and microstructures of muscle in broilers were investigated. A total of 105 mixed-sex Arbor Acres broilers were divided into three treatment groups: i) 45-min transport without rest (T group), ii) 45-min transport with 1-h rest (TR group), iii) 45-min transport with 15-min water-misting sprays with forced ventilation and 45-min rest (TWFR group). The results showed the TWFR group significantly increased (p<0.05) initial muscle pH ($pH_i$) and ultimate pH ($pH_u$) and significantly reduced $L^*$ (p<0.05), drip loss, cook loss, creatine kinase, lactate dehydrogenase activity, plasma glucose content, lactate and glycolytic potential when compared with other groups. Microstructure of the muscle from TWFR group broilers under light microscopy showed smaller intercellular spaces among muscle fibers and bundles compared with T group. In conclusion this study indicated water-misting sprays with forced ventilation after transport could relieve the stress caused by transport under high temperature, which was favorable for the broilers' welfare. Furthermore, water-misting sprays with forced ventilation after transport slowed down the postmortem glycolysis rate and inhibited the occurrence of PSE-like meat in broilers. Although rest after transport could also improve the meat quality, the effect was not as significant as water-misting sprays with forced ventilation after transport.

• Structural Engineering and Mechanics
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• v.70 no.4
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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.

• Journal of the Korean Solar Energy Society
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• v.27 no.3
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• pp.71-77
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• 2007

In past, parking lot was placed on the ground and for the reason air quality was not in problem. But recently parking lot has been placed under the ground and the air quality becomes problem. So in this study, the ventilation performance on the underground parking lot was estimated by using CFD software and alternative system was suggested. Three case studies are handled in this study. 1st case is just an underground parking lot. 2nd case is about an underground parking lot where has 4 fan rooms on each floor and 3rd case is about an underground parking lot where has 4 fan rooms and 30 guidance fans on each floor.

• Journal of Advanced Marine Engineering and Technology
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• v.24 no.1
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• pp.134-141
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• 2000

In this study, a scaled model chamber was built to investigate ventilation characteristics of the Under floor Air-conditioning System. Experimental study was performed in model for cargo-oil pump room with inlet and outlet by visualization equipment with laser apparatus. Instant simultaneous velocity vectors at whole field were measured by 2-D PIV system(CACTUS'2000) which adopted two-frame grey-level cross correlation algorithm. The flow pattern reveals the large scale counterclockwise forced-vortex rotation from upside louver to lower scupper toward diagonal corner and also found small eddies at bottom layer