• Korean Journal of Microbiology
• /
• v.39 no.4
• /
• pp.283-287
• /
• 2003

This study was performed to identify the microorganisms from air conditioners and to investigate hygiene management on air conditioners. Eight species of bacteria were isolated and identified from twenty samples of coolers in air conditioners; Pantoea sp., Bacillus circulans, Bacillus pumilus, Corynebacterium, Flavimonas oryzihabitans, Ochrobacterum anthropi, Micrococcus sp., and non fermented bacilli (NFB). One thousand and three hundreds twenty-two persons who used air conditioners in their houses were investigated about the state of hygiene management in their air conditioners. One thousand and one hundred thirty eight persons (86%) of the total investigated persons ventilated their air conditioners and 1,128 persons (85%) of them cleaned their air conditioners. However, 864 persons (66%) of them did not clean filters and 1,089 persons (82%) did not clean the heat exchangers, both of which air conditioners could be easily contaminated by microorganisms. From these results, we could conclude that the contaminants, bacteria as mentioned the above, in air conditioners could cause human disease such as respiratory infections if the number of bacteria increase in air conditioners. Thus, the removal of contaminants and the improved hygiene of the air conditioners can prevent human diseases caused by the released bacteria during the use of air conditioners.

• Proceedings of the KIEE Conference
• /
• 2001.07d
• /
• pp.2455-2457
• /
• 2001

The Remote controlled air conditioner is to effectively suppress the peak load generated from air conditioners in summer. It is important that remote controlled air conditioners are operated well in the real field. Almost 3,200 remote controlled air conditioners has been distributed as of the end of June, 2001. This paper describes a development of the certification system for the air conditioners.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.18 no.4
• /
• pp.63-71
• /
• 2015

Recently the roof gardening has become very popular and even on the apartment-veranda and on the roofs in high buildings many kinds of vegetables and berries are cultivated. And the demand of the nutritional supplement for the effective plant growth is also increasing. The general urban conditions are to be adapted for plant growth. A different hygroscopic and temperature-conditions after regions, sunshine and wind have strong influences on the plant growth and usually it is not optimal enough. It is because why a nutritional condition in soil for plant growth so important and essential. The usual compound-soil or -fertilizer cannot offer enough quantities of nutrients for plant growth and additional soil conditioner becomes more necessary. There are many kinds of soil conditioners like hydrogel in the market and we studied on Geohumus, Montigel and Geko, which are widely used in Europe and other countries. Water absorption and microbial immobilization with effective microorganisms were tested and compared. The EM solution was identified as bacteria, fungi and azotobacter etc. and they were immobilized at the soil conditioners at first. And the cultivated and immobilized at the soil conditioners EM-solution was added to the plant soil. 1 g of the soil conditioners absorbed ca. 20 g of water. The plant grew 10 cm more, got 3 times more branches and 2 times more fruits in the soil with soil conditioners immobilized with microorganisms. With water addition the plant with both conditions in the soil could stay fresh in comparison to without soil conditioners.

• The Journal of Korean Academy of Prosthodontics
• /
• v.41 no.1
• /
• pp.35-47
• /
• 2003

The dimensional stability of tissue conditioners characterizes the ability of the materials to yield accurate functional impressions of oral mucosa. This study evaluated the viscoelastic property and the linear dimensional changes with the factor of time and thickness of tissue conditioners ($COE-COMFORT^{TM}$, Visco-gel. $COE-SOFT^{TM}$, Soft-Liner). The thickness of these materials were changed (1.5mm, 3.0mm) and the percentage changes in dimension were measured at 1h, 12h, 24h, 36h, 3day, 7day after specimen preparation. From the results large differences appear between the various tissue conditioners. The results suggest that the period recommended for forming functional impression would be 2-3days after insertion in the mouth. in addition. it is important to select tissue conditioners suitable for functional impression because of the wide range of dimensional stability among the materials.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.15 no.6
• /
• pp.447-453
• /
• 2003

The air-side particulate fouling in the heat exchangers of HVAC applications degrades the performance of cooling capacity, pressure drop across a heat exchanger, and indoor air quality. Indoor and outdoor air contaminants foul heat exchangers. The purpose of this study is to investigate the cooling performance and pressure drop on the air-side particulate fouling of heat exchangers for air conditioners. Air conditioners being used in the field such as inn, restaurant, and office are collected in chronological used order. Test results show 15% decrease of the cooling capacity and 44% increase of the pressure drop for the 7 years air conditioners used in the seaside inn.

• The Journal of Korean Academy of Prosthodontics
• /
• v.33 no.3
• /
• pp.453-466
• /
• 1995

The use of tissue conditioners has come into favor for preprosthetic treatment and the treatment of Denture stomatitis, but the major problem in the use of the tissue conditioner is the growth of C.albicans. To compare the growth of C.albicans according to the type and the wearing period of the tissue conditioner, three commercial tissue conditioners were relined to intraoral plates which were delivered to 14 smoking, 12 nonsmoking healthy men. Cultures were made from the conditioner surface at 2, 7, 14, 21 days after after intraoral placement. The frequency of positive culture and colony counts of C.albicans were measured by imprint culture technique. The following results were achieved : 1. The frequency of positive cluture had increased significantly for all materials used. 2. The frequency of positive culture had incresed significantly around 2,14 days for day for COE-Comfort, SR-Ivoseal. 3. There were no significant difference in the colony counts of C.albicans among the mate rials used. 4. There were an over-all increase with the wearing period of tissue conditioners and significant increase around 2, 7, 14 days for COE-Comfort, and 2, 14 days for SR-Ivoseal, viscogel in colony counts. 5. Smoking had no effect on the growth of C.albicans. That is, there were no difference among the materials used in the growth of C.albicans. In the clinical application of tissue conditioners, we should avoid a long term use of it, but in inevitable cases, special disinfection procedures should be considered.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2008.05a
• /
• pp.426-430
• /
• 2008

Though the air-conditioners in each train model have almost identical function, there is incompatibility between them because of their different electric capacity and parts, even spares manufactures are different in the manufactured year. It cause over cost in the maintenance and repair of the each air-conditioner. In this paper, all the air-conditioners in each train model have been classified by their capacity and features so that grasp the operation status and the repair process of the air-conditioners, and draft systematically cost-effective solutions. By finding a way to deal with the emergency repair and extending the air-conditioner life though improvement of checking up progress, increase of passenger revenue can be reached considerably.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.15 no.12
• /
• pp.1035-1042
• /
• 2003

As the desire for a better condition in classroom increases, the distribution rate of warming and cooling conditioners increases. But it is known that according to the way by which the equipments put and are operated the comfortableness felt by persons who are in classroom can make a difference. Therefore, proper equipments in accordance with the size of classroom should be considered as well as operational methods when ceiling warming and cooling conditioners put. This study makes conclusions as follows through a simulation to get improvements in accordance with the size of classroom and to improve the heating performance of ceiling warming and cooling conditioners in classroom.

• Proceedings of the KIEE Conference
• /
• 2006.11a
• /
• pp.216-218
• /
• 2006

Economy of world has grown rapidly. This growth has increased the ownership of household electrical appliances including room air conditioners. The number of users of air conditioners is predicted to grow dramatically in the future. This paper discusses the present status of residential appliance energy efficiency standards around the world. The study found that the energy efficiency standards for room all conditioners would mitigate a significant amount of emissions in Korea.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.15 no.7
• /
• pp.611-617
• /
• 2003

The air-side particulate fouling in the heat exchangers of HVAC applications degrades the performance of cooling capacity, pressure drop across a heat exchanger, and indoor air quality. Indoor and outdoor air contaminants foul heat exchangers. The purpose of this study is to investigate the characteristics of the air-side particulate fouling materials in finned-tube heat exchangers of air conditioners. Air conditioners being used in the field such as inns, restaurants, and offices are collected in chronological order in use. Typical fouling materials on the heat exchangers include fibers and dusts ranged from 6.6 to 20.9 ${\mu}{\textrm}{m}$ in mass median diameter.