• KOREAN JOURNAL OF CROP SCIENCE
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• v.61 no.3
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• pp.163-170
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• 2016

Heading time is important element for yield and quality in crops. Among day length and temperature which influence on heading, temperature effect has not been investigated well. To investigate temperature effect on heading, heading date and plant growth characters were checked under the low and high temperature conditions in short day length. Analyzing heading date of six Korean varieties under the high and low temperature condition, heading date of varieties were delayed under low temperature. In the low temperature condition, dry weight and area of leaf were reduced. Varieties showing more delay of heading under low temperature also showed more reduction in leaf area. After selecting three varieties showing significant difference in leaf growth and heading date under different temperature conditions, nutrient contents of plant were analyzed. Nitrogen content was reduced in leaf and shoot under the low temperature condition. OsNRT2.3, nitrate transporter, was significantly down regulated in varieties showing more heading delay. Available phosphate content was decreased in leaf, but increased in shoot due to reduction of phosphate mobility. OsPT1, phosphate transporter regulating phosphate uptake, was more down regulated in varieties showing more heading delay. OsPT6, phosphate transporter regulating phosphate transport in plant, was also significantly down regulated in those varieties. With these data, we expected that active nitrogen and available phosphate uptake and transport in plant would increase leaf growth then might reduce heading delay under the low temperature condition.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.153-153
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• 2017

Potato (Solanum tubersosum L.) is susceptible to various environmental stresses such as frost, high temperature, and drought. Enhancement of potato drought tolerance can reduce yield loss under drought that has negative effect on potato tuber growth. Genetic engineering can be utilized to achieve this goal, but such approaches using endogenous potato genes have rarely been applied. Since unpredictable global weather changes cause more severe and frequent water limiting conditions, improvement of potato drought tolerance can minimize such adverse effects under drought and can impact on sustainable potato production. Genetic engineering can be utilized to improve potato drought tolerance, but such approaches using endogenous potato genes have rarely been applied. We were obtained AtbZIP28 gene transgenic potato plants. It is identified transcript levels at various stress conditions, polyethylene glycol (PEG), NaCl, abscisic ${\underline{acid}}$ (ABA). Also, For identification to regulate ER stress response genes in AtbZIP28 gene transgenic potato plant, we screened seven potato genes from RNA-seq analysis under TM treatment. Five and two genes were up- and down-regulated by TM, respectively. Their expression patterns were re-examined at stress agents known to elicit TM, DTT, DMSO and salt stress.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.334-334
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• 2017

Unstable soil moisture conditions often negatively affect the emergence, seedling establishment, and growth uniformity at the initial stage, and then reduce the grain yield and biomass in direct seeding cultivation for rice in rainfed fields. Therefore it is important to develop a technique to increase the rapid and stabilized seedling establishment and improve the uniformity of initial growth after sowing. This study aims to confirm results on seed priming effect of indoor using petri dish experiments can be reproduced in the field using container at Ghana. Twenty-seven rice varieties including of Oryza sativa L. and O. glaberrima Steud. were used in this study. The experiments using petri dish and container with different soil moisture conditions (5%, 10%, 15%, 20%) were compared. As a result, a significant positive correlation was found between the germination time uniformity in the primed seed of petri dish and emergence time uniformity in the primed seed of container in 10% and 15% soil moisture condition. A significant positive correlation was found between the germination time uniformity in the primed seed of petri dish and plant height in the primed seed of container in 10% soil moisture condition in O. glaberrima. This study concluded that the priming effect in petri dish demonstrate those in container in the field condition of Ghana in 10% and 15% soil moisture condition during seedling stage.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.53-53
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• 2017

Unstable soil moisture conditions often negatively affect the emergence, seedling establishment, and growth uniformity at the initial stage, and then reduce the grain yield and biomass in direct seeding cultivation for rice in rainfed fields. Therefore it is important to develop a technique to increase the rapid and stabilized seedling establishment and improve the uniformity of initial growth after sowing. This study aims to confirm results on seed priming effect of indoor using petri dish experiments can be reproduced in the field using container at Ghana. Twenty-seven rice varieties including of Oryza sativa L. and O. glaberrima Steud. were used in this study. The experiments using petri dish and container with different soil moisture conditions (5%, 10%, 15%, 20%) were compared. As a result, a significant positive correlation was found between the germination time uniformity in the primed seed of petri dish and emergence time uniformity in the primed seed of container in 10% and 15% soil moisture condition. A significant positive correlation was found between the germination time uniformity in the primed seed of petri dish and plant height in the primed seed of container in 10% soil moisture condition in O. glaberrima. This study concluded that the priming effect in petri dish demonstrate those in container in the field condition of Ghana in 10% and 15% soil moisture condition during seedling stage.

• Tunnel and Underground Space
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• v.21 no.3
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• pp.192-204
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• 2011

In this study, 3-D analyses were conducted while taking every construction stage into account. Then 2-D analyses were conducted which yield the same results with the 3-D results. The crown settlement normalized by the ultimate value was compared during the process to overcome the discrepancy caused by different dimensions. When a bench or a core is left uncut to give extra support to the face and eventually the whole excavation boundary, this extra supporting effect also has to be included in the analysis. In this study, this effect is also implemented in terms of the load distribution factor. When the length of the bench is very short compared to the diameter of the tunnel in such cases as in short bench cut or in mini-bench cut, the supporting effect of the face does not disappear even after the bench is completely excavated and supported since the face is still too close to the point of interest. The 4th load distribution factor was defined to stand for the advance of the face after the completion of the excavation cycle. The 4th load distribution factor turned out to be very useful in determining the load distribution factors when a tunnel is excavated by bench cut with various bench lengths under different initial conditions.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2002.04b
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• pp.41-47
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• 2002

Adverse environmental conditions such as drought, high salt and cold/freezing are major factors that reduces crop productivity worldwide. According to a survey, 50-80% of the maximum potential yield is lost by these 'environmental or abiotic stresses', which is approximately ten times higher than the loss by biotic stresses. Thus, improving stress-tolerance of crop plants is an important way to improve agricultural productivity. In order to develop such stress-tolerant crop plants, we set out to identify key stress signaling components that can be used to develop commercially viable crop varieties with enhanced stress tolerance. Our primary focus so far has been on the identification of transcription factors that regulate stress responsive gene expression, especially those involved in ABA-mediated stress response. Be sessile, plants have the unique capability to adapt themselves to the abiotic stresses. This adaptive capability is largely dependent on the plant hormone abscisic acid (ABA), whose level increases under various stress conditions, triggering adaptive response. Central to the response is ABA-regulated gene expression, which ultimately leads to physiological changes at the whole plant level. Thus, once identified, it would be possible to enhance stress tolerance of crop plants by manipulating the expression of the factors that mediate ABA-dependent stress response. Here, we present our work on the isolation and functional characterization of the transcription factors.

• Journal of Ocean Engineering and Technology
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• v.23 no.1
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• pp.89-95
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• 2009

The purpose of the present study was to evaluate the safety under extreme environmental conditions and the dynamic safety under service environment conditions, of oceanographic buoy mooring systems consisting of a variety of materials, including chain, wire rope, nylon rope, and polypropylene rope. For the static safety assessment of a mooring system, after the calculation of external forces and the division of a mooring system into finite elements, the numerical integral was conducted to yield the elemental static tension until satisfying the geometrical convergence condition. To evaluate the dynamic safety, various processes were considered, including data collection about the anticipated areas for mooring, a determination of the parameters for the interpretation, the interpretation of the dynamic characteristics based on an analytic equation that takes into account the heave motion effect of a buoy hull and a mooring system, and a fatigue analysis of the linear cumulative damage. Based on the analysis results, a supplementary proposal for a wire rope that has a fracture in an actual mooring area was established.

• Earthquakes and Structures
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• v.19 no.5
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• pp.395-409
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• 2020

With verifications through many relevant researches in the past few decades, adopting the equivalent lateral force procedure for designing seismically isolated structures as a preliminary or even final design approach has become considerably mature and publicly acceptable, especially for seismic isolation systems that mechanically exhibit bilinear hysteretic behavior. During the design procedure, in addition to a given seismic demand, structural designers still need to previously determine three parameters, such as mechanical properties of seismic isolation systems or design parameters and performance indices of seismically isolated structures. However, an arbitrary or improper selection of given parameters might cause diverse or even unacceptable design results, thus troubling structural designers very much. In this study, first, based on the criterion that at least either two design parameters or two performance indices of seismically isolated structures are decided previously, the rationality and applicability of design results obtained from different conditions are examined. Moreover, to consider variations of design parameters of seismically isolated structures attributed to uncertainties of mechanical properties of seismic isolation systems, one of the conditions is adopted to perform bounding analysis for seismic isolation design. The analysis results indicate that with a reasonable equivalent damping ratio designed, considering a specific variation for two design parameters (the effective stiffness and equivalent damping ratio) could present more conservative bounding design results (in terms of isolation displacement and acceleration transmissibility) than considering the same variation but for two mechanical properties (the characteristic strength and post-yield stiffness).

• Journal of the Korean Society of Food Science and Nutrition
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• v.14 no.4
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• pp.387-390
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• 1985

The effect of extracting conditions on the content of inorganic compounds of red ginseng extract was studied with respect to the change in ethanolic concentration ranges of $0{\sim}90%$ and temperature of $70{\sim}100^{\circ}C$ during $1{\sim}5$ times of extraction. Each extraction time was taken 8 hours at given temperature. Little effect of temperature on inorganic compounds was observed, while higher ethanol concentrations, particularly higher than 70%, were resulted a significant decreased in their contents. The yield of inorganic compounds in water was shown 80% over after 3rd extraction, while content of crude ash was observed similar tendency and their contents were significant increased in water than in 70% ethanolic concentration. In the process of extraction with water, 1.55% of the potassium content was the highest value, and the smallest was 11ppm of the copper. But in the extraction ratio to raw mateirls, the highest ratio was 91.4% of the calcium, and smallest was 30.4.% of the magnesium.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.381-384
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• 2002

Response surface methodology (RSM) was successfully applied to optimize for the production of Ganoderma lucidum in batch fermentations using the whey (40,000 mg latose/L) as substrate. This study was performed according to the central composite design (CCD) with respect to pH and temperature, where the designed intervals were 3.3$22.9^{\circ}C$$37.1^{\circ}C$, respectively. A second-order factorial design of the experiments was used to build empirical models providing a quantitative interpretation of the relationships between the two variables. The optimum conditions to maximize the production of G. lucidum were pH 4.2 and $28.3^{\circ}C$. At optimum conditions, the mycelial dry weight (MDW) and residual soluble COD (SCOD) were simultaneously used to evaluate the biokinetic coefficients assocoated with substrate inhibition model by nonlinear least squares method with 95% confidence interval. The. maximum microbial growth rates (${\mu}m$), half saturation coefficient ($K_s$), and the inhibition substrate concentration ($K_{is}$) were determined to be 0.095 l/hr, 128,000 mg SCOD/L and 49,000 mg SCOD/L, respectively. And the microbial yield coefficient (Y), biomass decay rate coefficient ($K_d$), and the maintenance energy coefficient ($m_s$) were determined to be 0.37 mg MDW/mg SCOD, 0.001 1/hr, and 0.0015 1/hr, respectively.