• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.5
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• pp.2086-2091
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• 2013

One of the most important objects for the industrial ventilation is to protect worker's health from the harmful substances. Mainly in industrial ventilation, the harmful substances broken out through manufacturing process are to be quickly emitted outside. Recently the importance of the industrial ventilation increases with the recognition change of industrial ventilation from manufacturing focusing to human focusing. In this paper, the air flow simulation inside the coating room is performed. All the coating room and the ventilation system are modeled by SolidWorks program and air flow distribution and ventilation performance are analyzed by Flow simulation program. And the air flow directions and the air flow velocities inside the coating room are enhanced with the use of local ventilation.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.29 no.2
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• pp.63-67
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• 2017

The purpose of this study is to analyze the Age of Air and the Local Air-change Effectiveness of by field measurement. The indexes of Age of Air and Local Air-change Effectiveness are used to analyze the local ventilation effectiveness of multiple locations and are mainly evaluated using the computational fluid dynamics (CFD) method. In this study, measurement of the Local Air-change Effectiveness was based on ASHRAE 129. The performance of Local Air-change Effectiveness and the dependence of the outlet location on Local Air-change Effectiveness were analyzed. The results showed that a greater air-change rate (ACH) may not guarantee better local ventilation effectiveness.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.8 no.2
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• pp.178-185
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• 1998

In order to evaluate and improve the performance of local exhaust ventilation systems for two TCE degreasing (A, B) and two electroplating (C, E) and one acid dipping & plating (D) operations located in Kimhae, the performance test was conducted with trace gases and a thermal anemometer (Kanomax 24-6111, Japan). For the inadequately designed systems, the improvement and redesigns in compliance with recommendation by ACGIH was suggested. The results of performance test for each system are as follows; 1. System of Workplace A was generally well-designed. Actual exhaust air flow rate was in excess of 68% above the recommended standard exhaust air flow rate. 2. System of Workplace B was very well-designed and completely enclosed. 3. All systems of Workplace C including hoods were poorly-designed and actual exhaust air flow rates were insufficient for open tanks. All systems should be upgraded according to ACGIH recommendations. 4. Supply and exhaust air flow rate of push-pull exhaust systems in Workplace D should be greatly increased. The width of flange of dipping tank hood should be increased with the value suggested. 5. System of Workplace E was well-designed. Actual exhaust air flow rate was in excess of 54% above the required.

• Journal of Environmental Science International
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• v.13 no.4
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• pp.367-376
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• 2004

In urban area, thermal pollution associated with heat island phenomena is generally regarded to make urban life uncomfortable. To overcome this urban thermal pollution problem, urban planning with consideration of urban climate, represented by the concept of urban ventilation lane, is widely practiced in many countries. In this study, the prevailing wind ventilation lane of a local winds in Daegu during the warm climate season was investigated by using surface wind data and RAMS(Reasonal Atmospheric Model System) simulation. The domain of interest is the vicinity of Daegu metropolitan city(about 900 $km^{2})$ and its horizontal scale is about 30km. The simulations were conducted under the synoptic condition of late spring with the weak gradient wind and mostly clear sky. From the numerical simulations, the following two major conclusions were obtained: (1)The major wind passages of the local circulation wind generated by radiative cooling over the mountains(Mt. Palgong and Mt. Ap) are found. The winds blow down along the valley axis over the eastern part of the Daegu area as a gravity flow during nighttime. (2)After that time, the winds blow toward the western part of Daegu through the city center. As the result, the higher temperature region appears over the western part of Daegu metropolitan area.

• Journal of the Korean Institute of Gas
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• v.22 no.3
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• pp.74-83
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• 2018

Anyone who wants to install local ventilation system must obtain a permission from the Ministry of Employment and Labor even if he has permission from the Ministry of Environment. This is because not only the Atmospheric Environmental Protection Act, but also the manufacturing industry's hazardous risk prevention plan under Article 48 Clause 2 of the Industrial Safety and Health Act is to be submitted by 15 days before the construction. Under the current Environmental Protection Act, the Ministry of Environment regulates only the emission of pollutants from local exhaust ventilation systems into the atmosphere and the contents of workers' safety and health within industrial sites are managed by the Ministry of Employment and Labor. Even with the approval of the Ministry of Environment, the number of unsuccessful cases by the Ministry of Employment and Labor has increased, causing a growing discontent among the sites due to production delays and additional costs of improvement. In addition, local exhaust systems that are at greater risk of fire explosion have increased the risk of severe industrial accidents due to fire explosion. This is due to insufficient design of air volume, control speed, return speed, duct size, and risk of fire explosion. This is because the criteria and procedures for approval of local exhaust ventilation systems are similar, but the Industrial Safety and Health Act adds additional screening items for safety and safety of workers and fire and explosion. In this study, the Environment Ministry and the Employment and Labor Ministry seek to find a reasonable way to operate the system by comparing local exhaust ventilation system installation approval standards.

• Journal of the Korean Society of Safety
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• v.7 no.3
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• pp.30-34
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• 1992

This study is conducted to evaluate the airborne concentration of mercury, as well as installation and efficiency of local exhaust ventilation system for 57 factories manufactured fluorescence lamps, mercury lamps and thermometers for July and August 1990. Results and conclusion are as fellows : 1) Mercury treatment factories are 32 among 57 ones, which are 18 fluorescence lamp manufacturing ones and 6 mercury lamp ones and 3 thermometer ones and 5 other ones. 2) Mean airborne concentrations of mercury for factories manufactured mercury lamps are 0.01 mg/ ㎥ in injection process and 0.0155mg/㎥ in exhaust process, and mean airborne concentration of mercury for factories manufactured thermometer are 0.023mg/㎥ in injection process and 0.012mg/㎥ in selection process. All of these airborne concentrations of mercury are lower than PEL(Permissible Exposure Limit ), 0.05mg/㎥. 3) Mean airborne concentrations of mercury for factories manufactured fluorescence lamps are 0.094mg/㎥ in injection process and 0.087mg/㎥ in exhaust process, and 0.052mg/㎥ in sealing process and 0.085mg/㎥ in other process, respectively. All of these air borne concentrations of mercury are exceeded to PEL. More than 60% among 32 factories manufactured mercury are exceeded to PEL. 4) Nine factories among 18 factories manufactured fluorestence lamps are equipped with local exhaust ventilation system, and 7 factories among 9 factories are required for the improvement of suction capacity and structure. Five factories among 14 factories manufactured mercury lamps and the other ones are equipped with local exhaust ventilation system, and 2 factories are required for the improvement of suction capacity and structure.

• International Journal of Air-Conditioning and Refrigeration
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• v.7
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• pp.91-100
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• 1999

This paper investigates ventilation characteristics of an environmental chamber simulating an under-floor air conditioning system for isothermal and cooling supply air conditions. The tracer gas sulfur-hexafluoride (SF$F_6$) was injected into a supply duct using step-up and step-down methods. Local mean and room mean ages were calculated from the concentrations measured at internal points and at the exhaust duct. The air change efficiency of the chamber has been found to be greater in cooling conditions than in isothermal conditions. Also the room air change efficiency is not significantly affected but slightly improved by the presence of a supply diffuser.

• Proceedings of the SAREK Conference
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• 2007.11a
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• pp.76-81
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• 2007

The shopping center in underground passage increased for efficient space utilization in urban area. This study describes operation characteristics of all air type and hybrid type with local ventilation and fan coil unit fixed to ceiling. In order to compare energy saving, thermal environment and installation space, etc., integrated simulator with heat production and indoor distribution system is designed and constructed. Energy saving of the hybrid system is calculated as over 30% compared to conventional all air type. And also the results showed that humidity decreased about 6%, also indoor thermal distribution is improved as temperature variation of around $1^{\circ}C$.

• Tunnel and Underground Space
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• v.27 no.1
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• pp.1-11
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• 2017

Most of the local limestone mines are developed as large-opening underground mines, while mine ventilation is heavily dependent on the natural ventilation and auxiliary systems, rather than the mechanical ventilation system using main fans. The current auxiliary ventilation system with fan and ducting requires optimization since enhanced deployment of diesel equipment demands higher airflow rate and the associated cost is expected to be too excessive for the local mine operators. This paper aims at optimizing the fan capacity for the working site ventilation through comparing the fan pressure in the mine airway and the ventilation efficiency of an axial-flow fan and a propeller fan developed in this study.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.10
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• pp.982-992
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• 2001

In this paper, the performance of ventilation equipments in enclosed parking garages were investigated for several air distribution systems by numerical method. Air change effectiveness of the non-mixing system was 0.42. It meant that more supply air as much as the design supply air was needed to maintain good indoor air quality. In the high speed nozzle ventilating system which is most expensive one, air change effectiveness was 0.54. Therefore this system satisfied to ventilation design. In the jet fan ventilating systems, air change effectiveness for jet fan ventilating system-A with 18 jet fans and jet fan ventilating system-B with 6 jet fans in circulation mixing arrangement were 0.565 and 0.42 respectively. Jet fan ventilating system-C with 6 jet fans in transport mixing arrangement was 0.535. Jet fan ventilating system-A and jet fan ventilating system-C met the ventilation design. But velocity in jet fan ventilating system-A was over 2.0m/s which is inappropriate in human comfort. Therefore this system is not proper to ventilation. Jet fan ventilating system-C was the optimum one for enclosed parking garages among 5 systems examined in this paper.