• Air Cleaning Technology
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• v.5 no.2 s.17
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• pp.16-25
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• 1992

• Air Cleaning Technology
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• v.2 no.1 s.5
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• pp.3-15
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• 1989

• Air Cleaning Technology
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• v.2 no.2 s.6
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• pp.60-68
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• 1989

• 전기산업
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• v.2 no.3
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• pp.29-37
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• 1991

• The Monthly Technology and Standards
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• s.74
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• pp.61-62
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• 2008

• Product Safety
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• no.3 s.172
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• pp.60-61
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• 2008

• Tunnel and Underground Space
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• v.24 no.6
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• pp.464-472
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• 2014

In large-opening room-and-pillar mining sites, particularly without the devices for the ventilation control, the airflow pattern created by the local fan operation is too complicated to quantify and also shows low ventilation efficiency. This study aims at performing a series of CFD analysis for the so-called venturi effects of the local fans; the effects of increasing airflow rate along the axis downstream of fan resulting from increased kinetic energy and subsequently decreased static pressure in the downstream. Effects of the fan type and installation height are compared. 1 vane-axial fan and 2 propeller fans are analyzed for their venturi effects, while the vane-axial fan was installed at the height of 1.0, 1.5 and 2.0m for comparison. The results can be applied to improve the economy and efficiency of local fans for securing better air quality and work environment management.

• Journal of the Korean Geographical Society
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• v.42 no.3 s.120
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• pp.332-343
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• 2007

This study aims to examine the distribution of heat waves and to understand its cause for 33 years$(1973\sim2005)$ from 60 weather stations in Korea. Heat wave is defined as a period of 3 or more days with a daily maximum temperature exceeds the 95th percentile. In the inland of Chungcheong region, the Chungcheong western costal region, the inland of Jeolla region, the inland of Gyeongsang region and the southern region of Jeju island, heat wave days appeared more than 160 days. In the middle region of eastern costal and the northern region of Jeju island, heat wave days were less than 110 days. In regions that were heavily influenced by southwesterly winds during the occurrence of heat waves, such as the inland of Chungcheong region, the Chungcheong western costal region, the inland of Jeolla region and the inland of Gyeongsang region, heat waves continued for the longer term.

• Tuberculosis and Respiratory Diseases
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• v.45 no.2
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• pp.416-420
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• 1998

Flow-volume loop is known to be useful in the diagnosis of upper airway obstruction. In cases of tracheal obstruction, characteristic features such as fixed or variable upper airway obstruction patterns give clue to the diagnosis. But the flow-volume loop of unilateral mainstem bronchial stenosis is not known well. There is controversy in patterns of flow-volume loop in unilateral mainstem bronchial stenosis (restrictive pattern or biphasic pattern). We report a case of biphasic flow-volume loop in left mainstem bronchial stenosis(4-5 mm in diameter) as a sequela of endobronchial tuberculosis, which recovered normal flow-volume loop after metallic stent insertion and 2 months later showed reappearance of biphasic pattern because of restenosis of left mainstem bronchus due to growth of granulation tissue at the stent site.

• Journal of Korean Tunnelling and Underground Space Association
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• v.11 no.4
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• pp.411-417
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• 2009

The thermo-flow field in road tunnel is influenced by some facts such as piston effect of vehicle's move, operation of ventilation facilities, natural wind and buoyancy effect of fire plume. Among those, piston effect is one of primary causes for formation of air flow in road tunnel and has an effect on initial direction of smoke flow in tunnel fire. In this study to analyze the unsteady flow in the tunnel caused by the run of vehicle, the experimental study of vehicle-induced unsteady flow on a reduced-scale model tunnel is presented. While the three types of vehicle shape such as basic type of rectangular shape, diamond-head type and stair-tail type are changed, the pressure and air velocity variations with time are measured. The rising ratio of pressure and velocity are in order of "basic type of rectangular shape > stair-tail type > diamond-head type". The experimental results would be good data for development of a numerical method on the vehicle-induced unsteady tunnel flow.