• Journal of Korean Society of Forest Science
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• v.101 no.2
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• pp.175-184
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• 2012

This study was conducted to develop new mattress systems with vegetation base materials for protecting stream bank and rapid rehabilitation. Vegetation base materials are primarily compounded with fine soil, organic composts and peat moss as plant fibers, a water retainer and a soil improver. Peat moss can usually provide necessary natural fibers and organic materials in soil. Especially, peat moss can absorb up to 25 times its own weight in water and is therefore valued as a water retainer to prevent drying effect of vegetation base materials which can harm the growth of vegetation in mattresses. Normally mattress systems resist the lateral earth pressures or stream power by their own weight. Therefore, filled materials must have suitable weight, compressive strength and durability to resist the loading, as well as the effects of water and weathering. In this project, 100 to 200-mm clean, hard stones were basically specified, and about 50-mm rubbles were also used. Test application of new mattress system carried out in the stream bank of a small stream in the Gwangreung experimental forest, belonging to Korea Forest Research Institute (KFRI) in December 16th, 2006. As a result of the monitoring of vegetation coverage of test application plots (each plot size is 4 by 2 m), the coverage of all plots reached 100% in the end of May, 2007 (approximately 50 days passed after the first gemination of vegetation). The coverage of the plots using big hard stones and organic composts and the plots containing peat moss increased more rapidly. The results show that peat moss is effective to retain soil moisture and establish more sound environment for vegetation gemination.

• Journal of Chest Surgery
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• v.29 no.5
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• pp.504-509
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• 1996

When a valve prosthesis is to be implanted in the aortic position, simple interrupted suture, figure-of- eight suture, or horizontal mattress suture technique is used as a suture method. However, the suture techniques may be unacceptable for aortic valve replacement in patients with friable annulus caused by some lesions, such as endocarditis and degenerative change. We used an alternative technique for the aortic vlave replacement in 4 patients with valve endocarditis, ) patients with degenerative valvular lesion, and 1 with rheumatic valvular disease. Mattress sutures through the annulus were placed with pledgets on the ventricular side of the annulus, whi h resulted in implantation of the prosthesis at a supra-annular level. Mechanical valves of 21 mm or larger were implanted in the supra-annular position in all patients and there was no impeded motion of leaflets during the follow-up period of mean 13.3 mouths. The transvalvular pressure gradient was less than 6 mm Hg in 3 patients and 20 to 40 mm Hg in 5 patients. The supra-annular implantation of mechanical aortic valve using a vertical mattress suture technique may be a useful alternative method of aortic valve replacement for the selected patients with friable or destroyed aortic annulus.

• Water for future
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• v.36 no.1
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• pp.129-133
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• 2003

• Fire Protection Technology
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• s.56
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• pp.20-29
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• 2014

• Fire Protection Technology
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• s.55
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• pp.26-33
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• 2013

• Proceedings of the Korea Water Resources Association Conference
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• 2003.05b
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• pp.927-930
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• 2003

• Proceedings of the Korean Fiber Society Conference
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• 2003.10a
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• pp.79-80
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• 2003

In order to develop an indoor assistive mobility equipment, we paid attention to the mechanism of locomotion in a snail, or a terrestrial gastropod molluscs. It is known that the snail moves by propagation of a pedal wave generating on a pedal surface of the snail and a pedal locomotion has flexibility far ground condition. An air mattress with a function of a pedal-like locomotion mechanism was developed and the performance of the pedal locomotory air mattress as mobility equipment was discussed.

• Journal of the Korean Society of Safety
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• v.12 no.1
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• pp.94-100
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• 1997

The objective of this research is to study the formations of smoke layer in case of several furniture fires such as trashcan, carpet, mattress and wardrobe as a fire starter in a residential room by performing the experimental studies. The uniformly distributed fire in case of carpet showed that the ignition and the initial growth period were relatively short while the fully developed period was considerably long. The concentrated fires such as the trashcan, mattress and wardrobe showed that the ignitions and the initial growth periods were relatively long. The descending speed of the interface height was proportioned to the inflammability of the furniture and the spread of the fire. The time required to come down around 1m was within 1-3 minutes. The Interface heights for the furniture fires were around 1m as the steady state. However, at the time of the maximum temperature, the interface height was lowered to 0.25m-0.75m from the floor. The carbon dioxide concentration reached the highest while the oxygen concentration was minimum.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.05a
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• pp.103-104
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• 2013

As a result of experimenting 6 loading combustibles in domestic residential facilities by using Furniture Calorimeter, values of 2,391.26kW were appeared from sofas, 1,891.80kW from drawers, 1,778.95kW from mattress, 1,104kW from chairs, 291kW from tables, and 135.09kW from TV. Also, if applying α value of fire growing rate by classifying fire- growing speeds at NFPA 72 (National Fire Alarm Code 2007, Annex B), mattress can be defined as Ultra-Fast, sofa and drawers Fast, TV Slow, tables Slow, and chairs Medium.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 1997.11a
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• pp.477-483
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• 1997

Experiments have been performed to investigate the formation of smoke layer in case of several furniture fires such as trashcan, chair, carpet, sofa, mattress, and wardrobe in a residential room. As a result of the present investigation, the uniformly distributed fire of carpet showed that the ignition and the initial growth period were relatively short while the fully developed period was considerably long. The concentrated fires such as mattress and wardrobe showed that the ignition and the initial growth period were relatively long. The descending time of the interface heights was within 1-3 minutes to reach around 1m. However, the interface height was lowered to 0.25-0.75m above the floor at the time of the maximum temperature.