• Food Science and Preservation
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• v.8 no.4
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• pp.356-361
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• 2001

This study was conducted to improve the storability of onion bulbs by assembly simple house storage and the reduce the rotteness caused by field open storage. Allium cepa cv. Changnyungdeago, late strain was used for the test at the storage condition of natural ventilation of levels 2, forced ventilation of levels 2, field open storage and 75mm, 100mm, and 125mm ventilating holes. Mean tamperature and relative humidity were not significantly different by ventilation conditions. Mean temperature was lower in forced ventilation than that of in natural ventilation and non-ventilation, and relative humidity was a little higher in ventilation treatment than those of the others. Weight loss of onion bulbs were 2.5%, 2.9%, 3%, 4.3% in field open storage, non ventilation, natural ventilation of levels 2 and forced ventilation of levels 2 respectively. Rotting rate in natural ventilation of levels 2 and farced ventilation of levels 2 were 27.7% and 25.4% respectively but 34.6% and 37.8% in non ventilation and field open storage. Therefore, the treatment of ventilation reduced the rotteness of storage onion bulbs. The smaller the size of a ventilating hole, the lower mean temperature was maintained. The relative humidity was some high in July, but didn’t showed significantly difference in August and September. With small size of a ventilating hole, the strong wind velocity was obtained, and wind velocity by position was weaker in the middle part than both ends. Rutting rates in 75㎜, 100㎜, and 125㎜ ventilating holes were 17.9%, 15.3% and 14.1% respectively.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.38 no.9
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• pp.4-9
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• 2009

초고층 공동주택에 설치되는 주방 및 욕실의 배기를 외부로 배출하는 방법은 공용유도관로인 수직덕트를 설치하고 그 상부말단에 하이브리드 루프팬의(hybrid roof fan)이 설치하는 것이다. 하이브리드 루프팬의 기능은 자연통풍력이 약한 하절기는 강제적으로 루프팬에 의해 구동하고 자연배기를 수행할 수 있을 정도로 자연통풍력이 큰 동절기는 루프팬을 운전하지 않는 기능을 보유하도록 유도하는 것이다. 본 고는 이러한 하이브리드 루프팬의 운전조건을 53층 높이의 임의 공동주택에 대해, 수직덕트의 선정한 후, 제시하고자 한다.

• Korean Journal of Food Science and Technology
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• v.14 no.3
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• pp.271-275
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• 1982

Low-temperature in-bin drying with high-moisture paddy were demonstrated and studied under local autumn weather condition. Paddy with the initial moisture content of about 24.5 percent in the steel storage bin(diameter: 3 m, height: 3.17 m) was uniformly dried to about 15 percent by continuous blowing of ambient air (average temperature: $10.5^{\circ}C$, RH: 58 percent) in the middle part of October. The amount of grain and grain height were 4.19 M/T and 90 cm, respectively. Total fan operation time was 288 hours and airflow rate was $4.81\;m^3/min/m^3$ of paddy. Mean drying rate was 0.03 percent per hour and enery requirement for fan operation was 0.38 KWh per kg water removed.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2001.05a
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• pp.117-120
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• 2001

This study is a preliminary research to develop design principles for environmentally friendly housing. The purposes of study are to investigate the literatures related passive design for summer and theory of ventilation, to analyze the indoor airflow patterns in traditional Korean house during summer, and to propose the design factors for effective passive cooling system. The analysis for airflow patterns was focused on the ‘An bang’and the ‘Dae Chung’in the ‘An Chae’of a traditional house located in Seoul. Field measurements of air temperature and air velocity were carried out at 30 different measuring points with 8 different window-opening conditions. The measurements were taken on the hottest summer days in August 2000. It is concluded that from an environmentally friendly standpoint design factors to control indoor thermal environment by a passive cooling system during the summer are as follows; ceiling structure has thermal performance like a time-lag effect, optimum height and length of eaves which can prevent sunlight and divert airflow toward the sitting level, building arrangement acceptable the prevailing wind, strategic window arrangement which makes cross ventilation possible (especially north-south) at the sitting level, window opening condition which is possible to intersect two cross-ventilation stream at the main living areas, northward windows remaining in shade to create the air pressure difference, and planning building shape like a bracket that has optimum width and depth.

• Korean Journal of Environmental Agriculture
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• v.28 no.3
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• pp.258-265
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• 2009

To develop environmentally friendly constructed wetlands(CWs) for treating domestic sewage which was produced in farming and fishing village, the efficiency of water treatment at different ventilation systems in the vertical bed, depths of horizontal bed, and sewage loads was investigated. In the vertical bed, BOD and COD by duplex ventilation system were lower than those by single ventilation system. But T-N and T-P concentrations by both ventilation systems in the vertical bed were little different. In the horizontal bed, BOD, COD, T-N and T-P in 1.0 m and 1.3 m depths were little different. To reduce the CWs' area and to improve the pollutant removal efficiencies, the optimum depth of horizontal bed was 1.3 m. In single and duplex ventilation CWs, the removal rate of BOD, COD, SS, T-N and T-P decreased slightly with the sewage load increases. In same sewage load conditions, the removal rates of BOD, COD, SS, T-N and T-P by duplex ventilation CWs were higher than those by single ventilation CWs. In summary, to effectively treat domestic sewage from farming and fishing village, the optimum constructed wetlands would be the duplex ventilation CWs.

• Journal of the Korea Organic Resources Recycling Association
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• v.22 no.3
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• pp.60-67
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• 2014

Exhaust system used in toilet and cooking place of high riser public house is roof fan of two basic types : natural roof ventilator and natural/forced roof ventilator. Natural/forced roof ventilator has a motor in the rotary shaft. There are many high riser public house in Korea. These buildings were not viewed as being major contributors to exhaust pollutants producted in indoor. It was because many engineers thought that exhaust in high riser building depend on stack effect. This study investigates on stack pressure determined by exterior pressure and the difference pressure control in exhaust stack used in high riser public house. This paper focuses mainly on the effect of the time interval for power supply of motor installed in roof fan with function of natural wind velocity and of exhaust air volume of toilet. It is observed there are higher exhaust efficiency than the existing natural roof ventilator.

• The Bimonthly Magazine for Agrochemicals and Plant Protection
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• v.5 no.10
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• pp.88-95
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• 1984

과수를 심고 자연상태로 두면 햇빛의 투여량과 통풍이 불량해진다. 이렇게되면 수관 외부에만 과실이 달리게 되고, 가지의 생육도 약하게 되어 병충해의 발생이 많게 된다. 정지전경을 하는 가장 큰 이유는 과수의 생리상태를 조절하므로서 나무의 골격을 형성하고 나무의 생장과 결실의 균형을 유지시키므로서 수세의 안정을 얻고, 결실을 조정하며 과실의 질을 향상시키고 병해충의 발생억제와 여러가지의 작업능룰을 좋게하는데 있는 것이다.

• The Science & Technology
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• v.32 no.9 s.364
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• pp.15-15
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• 1999

열사의 사막이 깔린 열대지방에서 중동인들은 어떻게 여름을 지내는가. 그들은 옷으로 온몸을 덮고 또 입까지 막고 다니는데 이것은 태양으로부터 피부가 타는 것을 막기 위해서이다. 또 중동인들이 가운처럼 생긴 검은색 로브를 헐렁하게 입고 다니는 것은 옷과 피부사이에 생기는 높은 온도의 공기를 아래쪽의 찬바람이 위로 밀어내 옷안에서의 자연스러운 통풍으로 더위를 이겨낸다는 것이다.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.10 no.5
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• pp.535-549
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• 1998

A numerical study for performance analysis of a counterflow type forced draft tower and natural draft cooling tower has been performed based on the method using the finite volume method with non-orthogonal body fitted and non-staggered grid system. For solving the coupling problem between water and air, air enthalpy balance, moisture fraction balance, water enthalpy balance, and water mass balance equations are solved with Navier-Stoke’s equations simultaneously. For the effect of turbulence, the standard k-$\varepsilon$ turbulent model is implied in this analysis. The predicted result of the present analysis is compared with the experimental data and the commercial software result to validate the present study, The predicted results show good agreement with the experimental data and the commercial software result. To investigate the influence of the cooling tower design parameters such as approach, range and wet bulb temperature, parametric studies are also peformed.

• Journal of the Korea Institute of Building Construction
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• v.4 no.2
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• pp.105-112
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• 2004

The objective of this study is to observe today's situation and direction in relation with the natural air-conditioning and heating system to expand the architectural utilization of natural management for human comfort and energy conservation in architectural design. Also this study to provide the fundamental knowledge and. design-techniques on environment-friendly architecture in connection with 'natural idea in architecture'. In accordance with this intention, this thesis is composed of the following contents : 1) to understand the fundermental concepts about natural air-conditioning and heating system, 2) to review the traditional characteristics in Korean and Southeast Asian architecture related to natural air-conditioning and heating system, 3) to examine modern design-techniques in relation with natural air-conditioning and heating system in the selected area, 4) to attempt to synthesize the whole situation. Environment-friendly architecture using natural ideas and design-techniques in architecture is very important architectural aspect in a current architecture, also for the future. In spite of general considerations, it is expected that this study is use to understand the principle and practical application of natural air-conditioning and heating system in architectural design.