• Korean Journal of Soil Science and Fertilizer
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• v.24 no.3
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• pp.200-205
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• 1991

To evaluate cold tolerance of rice cultivars on the basis of a relationship between cold tolerance in the field test and a biochemical character, transition-temperature of respiratory activity of mitochondria(TRM) which were isolated from different parts and at different growth stages and from etiolated rice seedling was investigated, and its relationship with degree of cold tolerance(DCT) in the field experiment was studied. The results obtained were summarized as follows. 1. The transition-temperature of respiratory activity of mitochodria (TRM) isolated from etiolated seedling ($25^{\circ}C$, two week-grown in the dark) of cold tolerant cultivars tended to be low, while that of cold susceptible cultivars to be high. 2. The correlation between TRM of etiolated seedling and the degree of cold tolerance(DCT) was $r=0.8935^{**}$ in 1988 and $r=0.8236^{**}$ in 1989. The correlation coefficient between TRM of 4-leaf seedling and DCT was $0.6239^{**}$ 3. TRM of young panicle was correlated with DCT except a few varieties. 4. TRM of seedling increased with growth as $12.5^{\circ}C$, $14.5^{\circ}C$, $15.5^{\circ}C$ and $16.5^{\circ}C$ at 1, 2, 3~4 and 5weeks respectively. 5. The transition temperature of mitochondrial respiratory activity was not significantly influenced by growth stages as $15.0{\sim}16.0^{\circ}C$ in Pungsanbyeo and $17.0{\sim}18.0^{\circ}C$ in Satbyelbyeo, while it was significantly different depending upon the degree of cold tolerance(tolerant, medium, susceptible).

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.91-91
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• 2017

Drought is the most serious abiotic stress limiting rice production. However, little progress has been made in the genetic analysis of drought tolerance, because it is a complex trait controlled by a number of genes and affected by various environmental factors. In here, we screened 218 rice genetic resources for drought tolerance at vegetative stage and selected 32 highly drought tolerant varieties in greenhouse. Under rain-fed conditions, Grain yield of Nagdong was decreased by 53.3% from 517 kg/10a to 241 kg/10a when compare to irrigation condition. By comparison, grain yield of Samgang was decreased by 23.6% from 550 kg/10a to 420 kg/10a. The variety Samgang exhibited strong drought tolerance and stable yield in rain-fed conditions and was selected for further study. To identify QTLs for drought tolerance, we examined visual drought tolerance (VDT) and relative water content (RWC) using a doubled haploid (DH) population consisted of 101 lines derived from a cross between Samgang (a drought tolerance variety) and Nagdong (a drought sensitive variety). Three QTLs for VDT were located on chromosomes 2, 6, and 11, respectively, and explained 41.8% of the total phenotypic variance. qVDT2, flanked by markers RM324 and S2016, explained 8.8% of the phenotypic variance with LOD score of 3.3 and an additive effect of -0.6. qVDT6 was flanked by S6022 and S6023 and explained 12.7% of the phenotypic variance with LOD score of 5.0 and an additive effect of -0.7. qVDT11, flanked by markers RM26765 and RM287, explained 19.9% of the phenotypic variance with LOD score of 7.1 and an additive effect of -1.0. qRWC11 was the only QTL for RWC to be identified; it was in the same locus as qVDT11. qRWC11 explained 19.6% of the phenotypic variance, with a LOD score of 4.0 and an additive effect of 9.7. To determine QTL effects on drought tolerance in rain-fed paddy conditions, seven DH lines were selected according to the number of QTLs they contained. Of the drought tolerance associated QTLs, qVDT2 and qVDT6 did not affect tiller formation, but qVDT11increased tiller number. Tiller formation was most stable when qVDT2 and qVDT11 were combined. DH lines with both of these drought tolerance associated QTLs exhibited the most stable tiller formation. These results suggest that qVDT11 is important for drought tolerance and stable tiller formation under drought stress condition in field.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.12 no.2
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• pp.227-233
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• 2001

Electromagnetic field characteristics of Reverberation chamber, which could be applicable for an alternative test facility of electromagnetic interference and radiated electromagnetic susceptibility have been investigated. To obtain the required field uniformity of reverberation chamber, Schroeder method Quadratic Residue Diffuser was designed to be applied to chamber. In this paper, 3 different types of diffusers depending on diffuser's periodic direction have been used to investigate field characteristics of each type by using FDTD numerical method. The results show all 3 types of reverberation chambers have below $\pm$3 dB tolerance of field uniformity characteristics, and the symmetrical, type 3, structure show better results among them.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.18 no.6 s.121
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• pp.577-583
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• 2007

The field uniformity inside the reverberation chamber has been improved using sets of quadratic residue diffuser (QRD). The electromagnetic field inside the reverberation chamber with the dimension of $100{\times}80{\times}80cm$ has been analyzed by the finite-difference time-domain(FDTD) method. The calculated fields in a $40{\times}30{\times}30cm$ test volume have been sampled to obtain a standard deviation and field uniformity. Results show that the standard deviation of the calculated field and uniformity have been improved by varying angles and orientation of the inclined surfaces of the QRDs installed inside the reverberation chamber.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.64 no.2
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• pp.109-126
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• 2019

Genetic resources of 84 species of Setaria italica BEAUVOIS, Sorghum bicolor, and Panicum miliaceum were collected to select the adaptable miscellaneous cereals in Saemangeum reclaimed land. The adaptability of Sorghum bicolor in reclaimed land was the highest among the three cereals cultivated on reclaimed land. The ratio of the average height of Sorghum bicolor plants cultivated in reclaimed land/normal field was 0.82, that of Panicum miliaceum was 0.61, and that of Setaria italica BEAUVOIS was 0.51. Three species of Sorghum bicolor, Satangdajuk, Kkamansusu, and Nampungcharl, were selected as potential genetic resources as they had excellent adaptability to reclaimed land. The yield of Satandaejuk on reclaimed land was 229.4 kg/10a, and the yield ratio of reclaimed land/normal field was 89.3%. The yield of Kkamansusu was 227.4 kg/10a, with reclaimed land/normal field ratio of 87.8%, and yield of Nampungcharl was 239.6 kg/10a, and reclaimed land/normal field ratio of 86%. In order to study the salt tolerance of selected genetic resources, we conducted salinity test. Salinity tolerance of Sorghum bicolor species-Satangdajuk, Kkamansusu, Nampungcharl was excellent compared to that of the other cereals. Among these, Satandaejuk had to highest salt tolerance level. Polyphenols, flavonoids, and detoxification of free radical were also studied. The anti-diabetic property of the cereals was also analyzed by ${\alpha}$-glucosidase inhibitory activity. We confirmed that the functionality of 3 lines in reclaimed land had improved in all the functional analysis categories when compared to that with yield in the normal field. Polyphenol, an antioxidant, increased in the range of 2~26% when cultivated in reclaimed land and the flavonoid content also increased from 8.5 to 55.6%. DPPH elimination capability, the ability to scavenge harmful reactive oxygen, also increased from 16.7 to 47% when cultivated in reclaimed land. The anti-diabetic activity and ${\alpha}$-glucosidase inhibition activity of selected Sorghum bicolor species-Satangdajuk, Kkamansusu, Nampungcharl also increased from 18.4 to 19.9% when cultivated on reclaimed land.

• Journal of Ginseng Research
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• v.23 no.2 s.54
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• pp.61-66
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• 1999

Experiments were carried out to examine the rusty tolerance in 61 inbred lines of ginseng cultivated in field, and chemical components were analyzed to clarify the difference between healthy and rusty ginseng roots. Among them, 10 lines showed rusty tolerance (RT) while 10 lines showed rusty sensitivity (RS). The content of phenolic compound in RT was lower than that in RS in cortex, epidermis and branch & fine roots, but it was not difference between RT and RS in stele. The contents of K, Ca, Na in RT were lower than RS in cortex, and the content of Mg, Fe, Na, Mn, AI, Si in RT were lower than RS in epidermis, and the content of Fe in RT were lower than RS in branch & fine roots, but mineral contents were not difference between RT and RS in stele. The content of phenolic compound in healthy cortex was lower than that in rusty cortex in same 6-year roots, but the mineral contents were not difference between healthy and rusty cortex in same 6-year roots. In root of seedlings, the contents of phenolic compound, K and Na in RT were lower than RS. It was suggested that the contents of phenolic compound, K and Na might be marker to select rusty tolerance ginseng lines.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.2
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• pp.100.2-100.2
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• 2014

The DOTIFS is a new multi-object Integral Field Spectrograph (IFS) planned to be designed and built by the Inter-University Center for Astronomy and Astrophysics, Pune, India, (IUCAA) for cassegrain side port of the 3.6m Devasthal Optical Telescope (DOT) being constructed by the Aryabhatta Research Institute of Observational Sciences, Nainital. (ARIES) It is a multi-integral field unit (IFU) spectrograph which has 370-740nm wavelength coverage with spectral resolution R~1200-2400. Sixteen IFUs with microlens arrays and fibers can be deployed on 8 arcmin field. Each IFU has $8.7^{{\prime}{\prime}}{\times}7.4^{{\prime}{\prime}}$ field of view with 144 spaxel elements. 2304 fibers coming from IFUs are dispersed by eight identical spectrographs with all refractive and all spherical optics. In this work, we show optical design of the DOTIFS spectrograph. Expected performance and result of tolerance and thermal analysis are also shown. The optics is comprised of f=520mm collimator, broadband filter, dispersion element and f=195mm camera. Pupil size is determined as 130mm from spectral resolution and budget requirements. To maintain good transmission down to 370nm, calcium fluoride elements and high transmission optical glasses have been used. Volume Phase Holographic grating is selected as a dispersion element to maximize the grating efficiency and to minimize the size of the optics. Detailed optics design report had been documented. The design was finalized through optical design review and now ready for order optics.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.5
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• pp.839-848
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• 2000

This paper presents the results of an electromagnetic field analysis for a reverberation chamber that is an alternative method of a shielded anechoic chamber, which is widely used for the analysis and measurement of electromagnetic interference and immunity test. Inside the defined test volume of the rectangular and triangular type, the Schroeder Quadratic Residue Diffuser was employed. FDTD(Finite-Difference Time-Domain) simulation method was applied to produce the field characteristics inside those reverberation chambers. According to the results, field uniformities on the aforementioned two types of reverberation chambers were correlated within $\pm$3dB, and $\pm$4.4dB tolerances, and rectangular type reverberation chamber shows an independent polarization result.

• Journal of the Korean Society for Nondestructive Testing
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• v.32 no.1
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• pp.56-63
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• 2012

In this study, a field applicability of reboiler tube was evaluated by comparing ECT signal with IRIS signal about wall loss rate and remaining wall thickness using worked austenite STS 316L ASME standard calibration tube. In the case of wall-loss rate, as a result, tolerance about $20%{\times}4$ flat bottom hole and 10% O D groove(ECT), 80% defect and 10% O D groove(IRIS) occurred up to ${\pm}15%$. In the case of remaining wall thickness, ECT was satisfied with the both tolerance, but tolerance about 80% defect occurred up to ${\pm}15%$ in IRIS. Therefore, if the IRIS is performed for interpretation of non-relevant indication and measurement of wall-loss rate after ECT, reliability is supposed to be improved.

• Horticultural Science & Technology
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• v.35 no.2
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• pp.220-231
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• 2017

Grafting using a pumpkin (Cucurbita sp.) rootstock is an effective way to improve cucumber (Cucumis sativus) resistance to a combination of chilling and salinity stresses. We evaluated the tolerance of 15 pumpkin cultivars to chilling, salinity, and combined stresses at the germination and seedling stages. Selected plant characteristics, including germination rate, germination potential, germination index, plant height, stem thickness, fresh weight, and dry weight, were analyzed. We used the unweighted pair group method with arithmetic mean for cluster analyses to determine the stress tolerance levels of the pumpkin cultivars. The 15 cultivars were divided into three clusters: tolerant, moderately tolerant, and susceptible to stress treatments. The stress tolerances of all cultivars were variable in the germination and seedling stages, and most cultivars were not tolerant to individual treatments of chilling or salinity stresses at both stages. These results suggest that identifying suitable cultivars for use as rootstock during cucumber grafting should involve the evaluation of stress tolerance during different growth stages. Additionally, cultivars tolerant to chilling stress may not be tolerant to salinity stress; therefore, the choice of pumpkin rootstock should depend on where the grafted plant will be grown. Cultivars tolerant to a combination of chilling and salinity stresses may be useful as rootstock for cucumber grafting. Our findings may serve as reference material for choosing appropriate pumpkin rootstocks for cucumber grafting.