• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 G
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• pp.2284-2289
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• 1998

The Rotor Stress Indicator is an integrated system of hardware and program components which has been designed to read an assortment of turbine temperature and speed input devices, perform an analysis of the temperature induced stresses and output pertinent temperature and stress information to guide the turbine operator during turbine prewarming, start-ups, load changes, and shut-downs. The purpose of the RSI is to provide guidance to the plant operator during startup, shutdown, loading, and unloading of the turbine. Since the stresses are a function of the temperature changes to which the turbine is exposed, the RSI also provides guidance for operation of the boiler main steam and reheat steam temperatures as they affect the rotor stresses. This may permit more efficient overall boiler turbine start-ups. In this paper, new rotor stress analysis algorithm for RSI is introduced and compared with present system which has been used in thermal power plant.

• Journal of Ginseng Research
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• 제4권1호
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• pp.104-120
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• 1980

The effects of temperature on transpiration, chlorophyll content, frequency and aperture of stomata, and leaf temperature of Panax ginseng were reviewed. Temperature changes of soil and air under spade roof were also reviewed. Growth responses of responses of ginseng plant at various temperature were assessed in relation to suseptibillity of ginseng plants. Reasonable management of ginseng fields was suggested based on the response of ginseng to various temperatures. Stomata frequency may be increased under high temperature during leaf$.$growing stage. Stomata aperture increased by high temperature but the increase of both frequency and aperture appears not enough for transpiration to overcome high temperature encountered during summer in most fields. Serial high temperature disorder, i.e high leaf temperature, chlorophyll loss, inhibition of photosynthesis, increased respiration and wilting might be alleviated by high humidity and abundant water supply to leaf. High air temperature which limits light transmission rate inside the shade roof, induces high soil temperature(optimum soil temperature 16∼18$^{\circ}C$) and both(especially the latter) are the principal factors to increase alternaria blight, anthracnose, early leaf fall, root rot and high missing rate of plant resulting in poor yield. High temperature disorder was lessen by abundant soil water(optimum 17∼21%) and could be decreased by lowering the content of availability of phosphorus and nitrogen in soil consequently resulting in less activity of microorganisms. Repeated plowing of fields during preparation seems to be effective for sterilization of pathogenic microoganisms by high soil temperature only on surface of soils. Low temperature damage appeared at thowing of soils and emergence stage of ginseng but reports were limited. Most limiting factor of yield appeared as physiological disorder and high pathogen activity due to high temperature during summer(about three months).

• 한국작물학회지
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• 제37권3호
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• pp.288-298
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• 1992

Since the major important factors limiting plant growth and crop productivity are environmental stresses, of which low temperature is the most serious. It has been well known that many physiological processes are alterant in response to the environmental stress. With regard to the relationship between plant hormones and the regulation of chilling tolerance in rice seedlings, the major physiological roles of plant hormones: abscisic acid, ethylene and polyamines are evaluated and discussed in this paper. Rice seedlings were grown in culture solution to examine the effect of such plant hormones on physiological characters related to chilling tolerance and also to compare the different responses among tested cultivars. Intact seedlings about 14 day-old were chilled at conditions of 5$^{\circ}C$ and 80% relative humidity for various period. Cis-(＋)-ABA content was measured by the indirect ELISA technique. Polyamine content and ethylene production in leaves were determined by means of HPLC and GC respectively. Chilling damage of seedlings was evaluated by electrolyte leakage, TTC viability assay or servival test. Our experiment results described here demonstrated the physiological functions of ABA, ethylene, and polyamines related to the regulation of chilling tolerance in rice seedlings. Levels of cis-(＋)-ABA in leaves or xylem sap of rice seedlings increased rapidly in response to 5$^{\circ}C$ treatment. The tolerant cultivars had significant higher level of endogenous ABA than the sensitive ones. The ($\pm$)-ABA pretreatment for 48 h increased the chilling tolerance of the sensitive indica cultivar. One possible function of abscisic acid is the adjustment of plants to avoid chilling-induced water stress. Accumulation of proline and other compatible solutes is assumed to be another factor in the prevention of chilling injuies by abscisic acid. In addition, the expression of ABA-responsive gene is reported in some plants and may be involving in the acclimation to low temperature. Ethylene and its immediate precusor, 1-amincyclopropane-1-carboxylic acid(ACC) increased significantly after 5$^{\circ}C$ treatment. The activity of ACC synthase which converts S-adenosylmethionine (SAM) to ACC enhanced earlier than the increase of ethylene and ACC. Low temperature increased ACC synthase activity, whereas prolonged chilling treatment damaged the conversion of ACC to ethylene. It was shown that application of Ethphon was beneficial to recovering from chilling injury in rice seedlings. However, the physiological functions of chilling-induced ethylene are still unclear. Polyamines are thought to be a potential plant hormone and may be involving in the regulation of chilling response. Results indicated that chilling treatment induced a remarkable increase of polyamines, especially putrescine content in rice seedlings. The relative higher putrescine content was found in chilling-tolerant cultivar and the maximal level of enhanced putrescine in shoot of chilling cultivar(TNG. 67) was about 8 folds of controls at two days after chilling. The accumulation of polyamines may protect membrane structure or buffer ionic imbalance from chilling damage. Stress physiology is a rapidly expanding field. Plant growth regulators that improve tolerance to low temperature may affect stress protein production. The molecular or gene approaches will help us to elucidate the functions of plant hormones related to the regulation of chilling tolerance in plants in the near future.

• 한국자원식물학회지
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• 제32권5호
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• pp.457-462
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• 2019

본 연구는 각시괴불나무 종자의 휴면유형과 발아특성을 구명하기 위하여 수행되었다. 수분흡수 실험결과, 각시괴불나무 종자는 수분흡수가 원활히 이루어졌다. 따라서, 물리적 휴면은 가지지 않는 것으로 판단된다. 각시괴불나무 종자는 탈리 시점에 미숙배를 가지고 있으며, 발아직전까지 배/종자 비율이 약 46% 증가하였다. 온도실험결과, $5^{\circ}C$에서는 발아가 전혀 이루어지지 않았다. $20^{\circ}C$에서는 파종 후 1주부터 발아가 시작되었으며 최종 발아율은 2주차에 86.7%였다. $15^{\circ}C$에서는 파종 후 2주부터 발아를 시작하였으며, 최종 발아율은 4주차에 75.0%였다. $25^{\circ}C$에서 파종 후 1주부터 발아가 시작되었으며 최종 발아율은 19주차에 48.3%였다. 결론적으로, 각시괴불나무 종자의 발아를 위한 최적온도는 가장 높은 최종 발아율과 가장 짧은 평균 발아 일수를 나타낸 $20^{\circ}C$이다. 각시괴불나무 종자는 $5^{\circ}C$를 제외한 모든 온도에서 4주 이내에 발아하였기 때문에 생리적 휴면은 관찰되지 않았다. 따라서, 각시괴불나무 종자는 오직 형태적 휴면만을 가지는 것으로 판단되었다.

• 한국작물학회지
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• 제39권6호
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• pp.571-576
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• 1994

본실험은 대맥의 미숙배 배양을 통한 육종기간을 단축하기 위하여 미숙배 배양시 식물체 유도, 생육 및 출수에 영향을 미치는 생장조절물질, 배의 성숙정도 및 저온처리효과를 구명하고자 실시하였으며 그 결과는 다음과 같다. 1. 미숙배 배양으로부터 줄기의 유도에는 생장조절물질이 첨가된 기본배지도 효과적이었으며, Kinetin 0.5mg/1와 $GA_3$ 5mg/l를 처리한 것 이 좋았으나 Kinetin농도가 높을 때에는 shoot 유도가 감소되었다. 2. 지베렐린을 1mg/l와 5mg/l 처리한 배지에서 초장, root길이, root수 등이 좋았으나 Kinetin이 처리된배지에서는 생육이 억제되었으며, 특히 뿌리의 생육을 억제하였다. 3. 유도된 식물체의 토양생존율은 Kinetin 5mg/l 처리시에 생존율이 가장 낮았고 무처리에서 가장 높았다. 4. 파성정도가 IV인 올보리의 20일배를 4주저온처리 하였을 때에 출수율이 높았고 출수하는데 소요되는 기간도 짧았다. 5. 저온처리후 Kinetin 5mg/l 처리한 것은 초장, root수, shoot수가 적은 반면 $GA_3$ 5mg/l 처리한 것은 생육이 좋았다. 6. 올보리는 생장조절물질과 저온처리에 따라 출수율에 차이를 보였으며 $GA_3$를 1mg/l처리하고 28일 저온처리하였을때 출수율이 좋았으며, 출수에 소요되는 기간이 짧았다.

• 한국토양비료학회지
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• 제47권6호
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• pp.571-578
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• 2014

The garlic cultivation area is moved by change of grown environment due to global warming. It is important to predict changes in cultivation area, quantity and quality of each crop. This study was carried out to estimate the yield and response of garlic growth by the rapid temperature changes in the greenhouse with thermostat control system. Seedlings of Namdo garlic were planted on September 27, 2012 and harvested on May 30, 2013. The used treatments for a rapid temperature change in March-April-May were T0 (control): $6.0-10.4-17.2^{\circ}C$, T1: $6.0-5.4(-5)-17.2^{\circ}C$, T2: $6.0-10.4-22.2(+5)^{\circ}C$ and T3: $6.0-5.4(-5)-22.2(+5)^{\circ}C$. Total dried weight per plant of garlic significantly increased by 5.0% for T2, but T1 and T3 decreased by 12.5 and 4.6%, respectively, compared to T0. Total yields of bulb within the temperature change as T2 and T0 increased significantly (p<0.05), as compared to T1. Decreasing temperature significantly (p<0.05) reduced plant height, SPAD reading, crude protein and fiber contents etc., as compared to T0 and T2. ABA contents gradually increased with time but IAA content rapidly decreased. Conclusively, growth and yield of garlic were more affected by decreased temperature than increased temperature at bulb development stage.

• The Korean Journal of Physiology and Pharmacology
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• 제24권4호
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• pp.349-362
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• 2020

Temperature affects the firing pattern and electrical activity of neurons in animals, eliciting diverse responses depending on neuronal cell type. However, the mechanisms underlying such diverse responses are not well understood. In the present study, we performed in vitro recording of abdominal ganglia cells of Aplysia juliana, and analyzed their burst firing patterns. We identified atypical bursting patterns dependent on temperature that were totally different from classical bursting patterns observed in R15 neurons of A. juliana. We classified these abnormal bursting patterns into type 1 and type 2; type 1 abnormal single bursts are composed of two kinds of spikes with a long interspike interval (ISI) followed by short ISI regular firing, while type 2 abnormal single bursts are composed of complex multiplets. To investigate the mechanism underlying the temperature dependence of abnormal bursting, we employed simulations using a modified Plant model and determined that the temperature dependence of type 2 abnormal bursting is related to temperature-dependent scaling factors and activation or inactivation of potassium or sodium channels.

• Mycobiology
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• 제46권3호
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• pp.287-295
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• 2018

In this study, we evaluated the effect of different temperatures (10, 20, 30, and $40^{\circ}C$) and relative humidities (RHs; 12, 44, 76, and 98%) on populations of predominant grain fungi (Aspergillus candidus, Aspergillus flavus, Aspergillus fumigatus, Penicillium fellutanum, and Penicillium islandicum) and the biocontrol activity of Pseudomonas protegens AS15 against aflatoxigenic A. flavus KCCM 60330 in stored rice. Populations of all the tested fungi in inoculated rice grains were significantly enhanced by both increased temperature and RH. Multiple linear regression analysis revealed that one unit increase of temperature resulted in greater effects than that of RH on fungal populations. When rice grains were treated with P. protegens AS15 prior to inoculation with A. flavus KCCM 60330, fungal populations and aflatoxin production in the inoculated grains were significantly reduced compared with the grains untreated with strain AS15 regardless of temperature and RH (except 12% RH for fungal population). In addition, bacterial populations in grains were significantly enhanced with increasing temperature and RH, regardless of bacterial treatment. Higher bacterial populations were detected in biocontrol strain-treated grains than in untreated control grains. To our knowledge, this is the first report showing consistent biocontrol activity of P. protegens against A. flavus population and aflatoxin production in stored rice grains under various environmental conditions of temperature and RH.

• Plant Resources
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• 제8권3호
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• pp.217-224
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• 2005

We tested the hypothesis that alpine plants have special physiological and biochemical mechanisms in addition to their structural adaptation in order to survive under extreme conditions. The photosynthetic organs of Pinus pumila were used to examine the seasonal changes in sugar concentration, antioxidative enzyme, and lipid peroxidation. The concentrations of sucrose, glucose, fructose and reducing sugar were the highest in the leaves in April. But sugar contents in buds and inner barks did not respond sensitively on temperature change. Meanwhile superoxide dismutase (SOD) activity responded sensitively on the change of temperature and SOD in all tissues maintained high activity in April. Meanwhile anthocyanin content increased rapidly in June but the increase of anthocyanin content was not enough to prevent their tissues from the damage by the exposure of high temperature or other stress. In conclusion, under low temperature condition, P. pumila increased the concentration of soluble sugars and SOD activity in their tissues in order to overcome extreme environmental condition. But in summer, these stress defense system against high temperature might be disturbed slightly. This results in the increase of malondialdehyde (MDA) contents in three tissues by lipid peroxidation.

• 한국자원식물학회지
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• 제33권2호
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• pp.106-115
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• 2020

본 연구는 봄 식물계절지수와 기온지표와의 관계를 알아보기 위해 지난 9년간(2010년-2018년) 대구수목원, 팔공산, 주왕산, 가야산에 공통적으로 생육하는 소나무, 일본잎갈나무, 신갈나무, 진달래, 생강나무, 당단풍나무 6종을 대상으로 발아, 개화, 개엽의 봄 식물계절 시기의 변화 경향과 기온간의 관계를 파악하였다. 기온의 변화는 9년동안2월 보다 3~4월의 월평균 기온이 증가하였으며, 지역별로 수목원과 팔공산의 평균기온이 높았다. 발아, 개화, 개엽은 수종별로 생강나무가 가장 빠르며 소나무가 가장 느렸고, 지역별로 수목원에서 가장 빨리 식물계절시기가 도래하였다. 봄 식물계절시기는 -1.267~-6.151일/9년 정도 앞당겨지고 있는 경향을 보이는데 소나무(-6.151일/9년)가 가장 크며, 진달래(-1.267일/9년)의 변화율이 가장 낮았다. 발아, 개화, 개엽에서 모두 유의한 값을 보이는 수종은 진달래와 소나무로서 이들은 1월~3월 평균기온과 상관관계를 보였다. 봄 식물계절지수(SPI)의 시계열 변화를 확인한 결과 4개 지역의 변화율이 모두 음의 값으로 식물계절 시기가 모두 빨라지고 있었다. 그 중 수목원, 팔공산 및 가야산과 같은 내륙지역일수록 변화율이 컸으며, 다소 거리가 떨어진 주왕산의 경우 변화율이 조금 낮게 나타났다.