• 생물환경조절학회지
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• 제18권3호
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• pp.200-207
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• 2009

This study was conducted to analyze the variations of air temperature, relative humidity and pressure in a low pressure chamber for plant growth. The low pressure chamber was composed of an acrylic cylinder, a stainless plate, a mass flow controller, an elastomer pressure controller, a read-out-box, a vacuum pump, and sensors of air temperature, relative humidity, and pressure. The pressure leakage in the low pressure chamber was greatly affected by the material and connection method of tubes. The leakage rate in the low pressure chamber with the welding of the stainless tubes and a plate decreased by $0.21kPa{\cdot}h^{-1}$, whereas the leakage in the low pressure chamber with teflon tube and rubber O-ring was given by $1.03kPa{\cdot}h^{-1}$. Pressure in the low pressure chamber was sensitively fluctuated by the air temperature inside the chamber. An elastomer pressure controller was installed to keep the pressure in the low pressure chamber at a setting value. However, inside relative humidity at dark period increased to saturation level.. Two levels (25 and 50kPa) of pressure and two levels (500 and 1,000sccm) of mass flow rate were provided to investigate the effect of low pressure and mass flow rate on relative humidity inside the chamber. It was concluded that low setting value of pressure and high mass flow rate of mixed gas were the effective methods to control the pressure and to suppress the excessive rise of relative humidity inside the chamber.

• The Korean Journal of Ecology
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• 제23권4호
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• pp.293-298
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• 2000

To study the effect of global warming on the growth of plants and plant populations throughout their life cycle under a field-like condition, we constructed a Temperature Gradient Chamber (TGC) in Tsukuba, Japan. The chamber had slender shape : 30 m long. 3 m wide, and 2.5 m high. That satisfactory performance was confirmed by a test throughout all seasons in 1998: the projected global warming condition in the near future was simulated. That is, independent of a great daily or seasonal change in ambient meteorological conditions, air temperatures at the air outlet were warmed 5$^{\circ}C$ higher than those at the ambient (the annual mean was 14.3$^{\circ}C$) with precision of ${\pm}$0.2$^{\circ}C$ (the annual means were 19.2$^{\circ}C$) with a rising rate of approximately 1$^{\circ}C$ every 5 m. This chamber will enable us to study the effects of global warming on growth of plants and plant populations because their abilities to control air temperature are excellent. TGC is expected that it would be utilized for studying the effect of global warming on plant growth under natural weather conditions.

• 화훼연구
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• 제17권4호
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• pp.266-270
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• 2009

깽깽이풀의 임의 개회조절을 목적으로 입실시기, 저온처리 등이 맹아, 생장 및 개화 등에 미치는 영향을 살펴보았다. 입실시기에 따라서는 8월 20일부터 12월 20일까지 입실한 묘는 모두 맹아가 되지 않았다. 그러나 1월 20일과 2월 20일에 입실한 묘는 모두 맹아되어 개화되었다. 저온처리 개시시기와 처리기간이 깽깽이풀의 생장과 개화에 미치는 영향을 살펴본 결과는 8월 고온기에는 60일간의 저온을 받게 되면 맹아하여 개화하였다. 그러나 9월 20일 이후에는 30일간의 저온처리만으로도 거의 전개체가 맹아하여 개화하였다. 이미 저온처리를 한번 받아 휴면이 타파된 주를 재차 저온처리를 하여 2차 개화를 유도한 결과, 실험에 사용된 전 개체 모두 재맹아하였고 이중 70%인 7개체가 개화가 되었다.

• Journal of Forest and Environmental Science
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• 제28권1호
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• pp.12-18
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• 2012

Like any other natural resources, forest flora may experience the extreme threat of elevated temperature and saline water submergence at different stages of their lives i.e. from germination to maturity due to climate change effects. The overall aim of the study was to measure the effect of higher temperatures along with saline water irrigation on survival and initial growth during seedling stage of Artocarpus chapalasha. The experiment was conducted in temperature- humidity-photoperiod regulated plant growth chamber during stipulated period to measure the growth performance of randomly selected seedlings. Within three different elevated temperatures viz. $30^{\circ}C$, $32^{\circ}C$ and $34^{\circ}C$, the seedlings were given three different saline conditions such as 0.5 g/L, 1.5 g/L and 2.5 g/L NaCl concentrations. Results found from the experiment was that, seedlings of Artocarpus chaplasha reared at different temperatures and saline water treatments showed stunted growth than reared at existing outdoor temperature ($26.31^{\circ}C$) irrigated with regular fresh water. Seedling growth at three different parameters such as height, collar diameter and number of leaves showed that with increasing temperature individuals respond negatively to increasing saline condition. The seedling's growth occurred at every day in height, collar diameter and leaf. However, growth rate reduced later during the observation. The combined effect of high salinity and higher elevated temperature results in seedling mortality. Therefore, Artocarpus chaplasha may not thrive at higher temperature and salinity intrusion at its early growing period in plantation and natural forest areas.

• 한국작물학회지
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• 제65권4호
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• pp.339-345
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• 2020

Recently, abnormal weather conditions, such as extreme high temperatures and droughts, have increased in frequency due to climate change, there has accordingly been growing concern regarding the detrimental effects on field crop, including soybean. Therefore, this study was conducted to examine the effects of increased temperatures on soybean growth and yield using a temperature gradient chamber (TGC). Two major types of soybean cultivar, a medium- seed cultivar such as Daepung-2 and a large-seed cultivar such as Daechan, were used and four temperature treatments, aT+1℃ (ambient temperature+1℃), aT+2℃ (ambient temperature+2℃), aT+3℃ (ambient temperature+3℃) and aT+4℃ (ambient temperature+4℃) were established to examine the growth response and seed yield of each cultivar. Seed yield showed a higher correlation with seed weight (r=0.713***) and an increase in temperature affected seed yield by reducing the single seed weight. In particular, the seed growth rate of the large-seed cultivar (Daechan) increased at high temperature, resulting in a reduction in the number of days for full maturity. Our results accordingly indicate that large-seed cultivar, such as Daechan, is potentially vulnerable to high temperature stress. The results of this study can be used as basic data in the development of cultivation technology to reduce the damage caused by elevated temperatures. Also, further research is required to evaluate the response of each process contributing to seed yield production under high temperatures.

• 인간식물환경학회지
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• 제22권6호
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• pp.575-582
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• 2019

Moss is used as an important material in indoor landscaping as well as outdoor landscaping. Moss is vivid green during growth and excellent in ornamental value. But when temperature drops, moss stops growth, turns brown or loses its ornamental value. In the present experiment, for the purpose of classifying native mosses according to the growth response to low temperature, the temperature of the plant growth chamber was set to 15℃/5℃ (16h/8h, day/night) and 5℃ (24h) for 8 weeks using nine native moss species. Thereafter, the temperature of the plant growth chamber was set to 20℃, and then the changes of moss block area and moss color were measured. The changes of moss block area and moss color were measured using a Photoshop program, after each moss block was photographed. As a result, Atrichum undulatum (Hedw.). Beauv., Etodon luridus (Griff.) A. Jaeger, Bachythecium plumosum (Hedw.) Schimp, Plagiomnium cuspidatum (Hedw.) T.J. Kop, and Hypnum plumaeforme Wilson showed a small decrease in moss block area at low temperature, and their recovery were the fastest at 20℃. These three species had higher green values at low temperature compared to other species, and the greenness increased rapidly at 20℃. On the other hand, Atrichum undulatum (Hedw.). Beauv., Marchantia polymorpha L., and Thuidium cymbifolium (Mitt.) A. Jaeger showed the smallest block area at low temperature and the lowest recovery even at 20℃. Their green values also decreased significantly at low temperature, and maintained low green value even at 20℃. These results showed that these three moss species are sensitive to low temperature. The remaining Myuroclada maximowiczii, Plagiomnium cuspidatum, and H. erectiusculum showed moderate responses to low temperature compared to other six species of mosses.

• 생물환경조절학회지
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• 제4권2호
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• pp.125-130
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• 1995

동계 시설내 온도 및 광도가 고추의 생장에 미치는 영향을 알기 위하여 생장상내에서 인공적으로 온도 3수준(10, 20 및 3$0^{\circ}C$)과 광도 3수준(5, 15 및 25klux)을 7주간 조합 처리한 결과 나타난 생장반응은 다음과 같다. 1. 생장상내에서 고추 시묘의 초장, 엽면적 및 건물중의 생장은 3$0^{\circ}C$$\times$25klux 처리구에서 가장 양호했고, 각 온도에서도 광도의 증가에 따른 생장의 증가반응이 뚜렷하였다. 2. 처리후 7주째의 생장량을 multiple regression polynomial로 수식화한 결과 초장, 엽수, 엽면적, 경건물 및 지하부 건물중은 수식고정이 적합하였다. 3. 지상부 건물중에 대한 다중 회귀식을 광도와 온도로 편미분한 이론치를 이용하여 단위온도 증가에 대한 단위광도의 향상도와 단위광도 증가에 대한 단위온도 증가의 반응표면을 도식화한 결과 저온화에서의 광도증가는 지상부 건물중 증가반응의 향상도를 크게 높였으나, 광도 10k1ux이하나 온도가 2$0^{\circ}C$이상에서는 온도의 역할이 더 크게 나타났다. 단위광도 증가에 대한 온도반응의 증가에서도 동일한 경향으로 나타나 온도와 광도의 강한 상보성을 나타내었다.

• 한국진공학회지
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• 제2권4호
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• pp.410-415
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• 1993

The direct growth OMVPE system, designed specificallyfor direct growth of Hg1-xCdxTe using annular rectant inlet inverted verticla (ARIIV) reactor, was constructed. This paper presents the detailed technical approach on a newly designed ARIIV reactor that increases Hg incorporation, imposes uniformity, and avoids the needs for temperature processing to create alloys by inter diffusion approach.

• 한국자원식물학회지
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• 제28권2호
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• pp.243-252
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• 2015

본 연구는 제주특산식물인 좀향유의 현지 내･외 보존을 위한 기초 연구로서 증식체계를 마련하고 전처리제 처리에 따른 발근 특성과 시비에 따른 유묘의 생장 효과를 등을 알아보았다. 온실과 밀폐상의 온습도 조사결과 평균 온도는 비슷하였으나 공중 습도는 온실보다 밀폐상이 높은 습도를 유지하였으며, 좀향유 삽목 후 온실은 10일, 밀폐상은 7일만에 최초 발근을 확인하여 밀폐상의 빠른 발근율을 보였으며 온실과 밀폐상에서의 생존율, 발근율, 뿌리수 등은 근소하게 밀폐상이 높게 조사되어 온실보다 밀폐상이 효과적이었다. 발근억제물질 제거를 위한 전처리제 처리는 AgNO₃ 77.5%를 제외한 다른 처리구에서 95% 이상의 높은 발근율로 조사되어 좀향유의 경우 발근억제 물질은 적은 것으로 판단된다. 유묘의 용기별 질소 시비량 및 Osmocote 시비시험 결과 시비량과 용기의 조건에 따라 생존율과 생장 등에 차이를 보였다. 배양판에서 완효성 비료인 Osmocote를 시비한 결과 생존율, 지상부, 지하부 생장 등이 가장 양호하여 좀향유의 유묘 증식을 위해서는 Osmocote 시비가 바람직 할 것으로 판단된다.

• 한국연소학회지
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• 제11권2호
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• pp.28-36
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• 2006

A constant volume combustion chamber was used to investigate the combustion characteristics. of homogeneous charge of methane-air mixture under various initial pressure, equivalence ratio and ignition times. The constant volume combustion chamber(CVCC) mostly has been studied by the experiments of visualization until now. So it is needed the numerical analysis of fluid and combustion characteristics in chamber by the more detail simulation. In this paper, the numerical analysis is tried to approach basically the homogeneous charge combustion phenomena under the various conditions, and the combustion phenomena in chamber is numerically analyzed by the commercial FIRE code. As a results, the combustion phenomena which were mean temperature, OH radical and reaction rate in chamber were investigated and it showed that the smallest flame growth occurs for the lean state and the increase of initial charged pressure condition due to the reduced OH radical.