• Korean Journal of Breeding Science
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• v.49 no.3
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• pp.250-255
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• 2017

'Hwaweon 7' was developed from a cross between the African upland cultivar, 'Moroberekan' and 'Ilpumbyeo' based on marker-aided backcross selection. The recurrent parent, Ilpumbyeo is a high grain quality cultivar with medium to late maturity. Hwaweon 7 is nearly isogenic to Ilpumbyeo except a small Moroberekan introgressed segment on chromosome 6 harboring genes related with spikelets per panicle and internode diameter. The preliminary and replicated yield trial was conducted at Chungnam National University and Chungcheongnamdo Agricultural Research & Extension (CARES), Yesan in 2010 and 2011. The local adaptability test was carried out by the National Seed Management Office (NSMO) in 2012 and 2013. This cultivar was registered to NSMO with a cultivar designated as "Hwaweon7". This cultivar averaged 80cm in culm length and has a medium growth duration. Milled rice of "Hwaweon7" is translucent and the grain quality traits are comparable to those of the recurrent parent. The average yield potential of Hwaweon 7 in grain was about 6.48 MT/ha at the ordinary fertilizer level for two years about 5.1% higher than that of Ilpumbyeo due to increase in spikelets per panicle. This variety is tolerant to lodging and the tolerance is due to the APO1 gene controlling the base internode diameter on chromosome 6 introgressed from the donor parent, Moroberekan. The Apo1 gene would be useful in enhancing resistance to lodging in rice breeding program.

• Genes and Genomics
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• v.40 no.12
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• pp.1351-1361
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• 2018

A new cold tolerant germplasm resource named glutinous rice 89-1 (Gr89-1, Oryza sativa L.) can overwinter using axillary buds, with these buds being ratooned the following year. The overwintering seedling rate (OSR) is an important factor for evaluating cold tolerance. Many quantitative trait loci (QTLs) controlling cold tolerance at different growth stages in rice have been identified, with some of these QTLs being successfully cloned. However, no QTLs conferring to the OSR trait have been located in the perennial O. sativa L. To identify QTLs associated with OSR and to evaluate cold tolerance. 286 $F_{12}$ recombinant inbred lines (RILs) derived from a cross between the cold tolerant variety Gr89-1 and cold sensitive variety Shuhui527 (SH527) were used. A total of 198 polymorphic simple sequence repeat (SSR) markers that were distributed uniformly on 12 chromosomes were used to construct the linkage map. The gene ontology (GO) annotation of the major QTL was performed through the rice genome annotation project system. Three main-effect QTLs (qOSR2, qOSR3, and qOSR8) were detected and mapped on chromosomes 2, 3, and 8, respectively. These QTLs were located in the interval of RM14208 (35,160,202 base pairs (bp))-RM208 (35,520,147 bp), RM218 (8,375,236 bp)-RM232 (9,755,778 bp), and RM5891 (24,626,930 bp)-RM23608 (25,355,519 bp), and explained 19.6%, 9.3%, and 11.8% of the phenotypic variations, respectively. The qOSR2 QTL displayed the largest effect, with a logarithm of odds score (LOD) of 5.5. A total of 47 candidate genes on the qOSR2 locus were associated with 219 GO terms. Among these candidate genes, 11 were related to cell membrane, 7 were associated with cold stress, and 3 were involved in response to stress and biotic stimulus. OsPIP1;3 was the only one candidate gene related to stress, biotic stimulus, cold stress, and encoding a cell membrane protein. After QTL mapping, a total of three main-effect QTLs-qOSR2, qOSR3, and qOSR8-were detected on chromosomes 2, 3, and 8, respectively. Among these, qOSR2 explained the highest phenotypic variance. All the QTLs elite traits come from the cold resistance parent Gr89-1. OsPIP1;3 might be a candidate gene of qOSR2.

• Korean Journal of Breeding Science
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• v.40 no.2
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• pp.173-177
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• 2008

A new peanut variety "Pungsan" (Arachis hypogaea ssp. hypogaea L.) was developed at the Yeongnam Agricultural Research Institute, NICS, in Milyang in 2007. It was derived from a cross between a short stem cultivar "Satonoka" and a high-yielding local cultivar "Yecheon". "Pungsan" is the Virginia plant type. It has 18 branches per plant and 40 cm of main stem height. Each pod with long-ellipse shaped large kernel has two grains with light-brown testa and 100 seed weight was 95g in the regional yield trials (RYT). "Pungsan" showed more resistant to web blotch compared with check variety. In the regional yield trials "Pungsan" was outyielded in grain yield to the check variety by 16% with 4.45 MT/ha for grain.

• Korean Journal of Breeding Science
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• v.43 no.3
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• pp.214-217
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• 2011

A light pink double freesia (Freesia hybrida Hort.) 'Pink Ribbon' was developed from a cross of breeding a line, 'Pink Jewel' derived 'Michelle' and 'Rossini' and 'Purple Rain' followed by seedling and line selections at the National Institute of Horticultural and Herbal Science (NIHHS), Rural Development Administration (RDA) in 2008. Growth and flowering characteristic tests were conducted from 2004 to 2007. 'Pink Ribbon' has double type flower with light pink color (RHS, RP66C). It has simultaneous flowering of many florets, good flower shape, upright leaves and stalks. The average cut flower yield of 'Purple Rain' observed in the greenhouse from 2005 to 2007 was 7.7 cuttings per plant. It has good production of cormlets, vigorous growth, too. 'Purple Rain' could be cultured under greenhouse conditions in Korea.

• Korean Journal of Breeding Science
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• v.40 no.2
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• pp.196-200
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• 2008

A new spary chrysanthemum (Dendranthema grandiflorum) cultivar 'Pinky' was bred from a cross between 'Rima' and 'Yen'. Progenies were investigated from 2004 to 2006 under shading culture in spring and retarding culture in autumn and the promising line was selected based on the performance of year-round production, white rust resistance and vase life. Pinky flowered around 20 October, and year-round production was possible by shading and lighting. Its flower was 3.1 cm in diameter, and had 38.4 petals and 26.8 flowers per stem in autumn. Its petal was narrow (0.4 cm) and pink with green in color at the flower center. Days to flower from short-day start for 'Pinky' was about 47 in spring. 'Pinky' showed a vase life of 20.9 days in autumn. This cultivar was commercially registered in 2007. 'Pinky' would be suitable for culture under the greenhouse and rain shelter condition in Korea.

• Korean Journal of Breeding Science
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• v.42 no.3
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• pp.248-251
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• 2010

A lemon double freesia (Freesia hybrida Hort.), 'Shiny Lemon' was developed from a cross between the domestic breeding lines ('Golden Crown' and 'White Wings') and 'Yvonne' followed by seedling and line selections at the National Institute of Horticultural and Herbal Science, Rural Development Administration (RDA) in 2007. Growth and flowering characteristic tests were conducted from 2003 to 2006. 'Shiny Lemon' has large double type flower with lemon color (RHS Y13D). It has multiple florets, good flower shape, and upright leaves and stalks. The average cut flower yield of 'Shiny Lemon' was 7.1 cuttings per plant in the greenhouse from 2005 to 2007. Additionally, it has good production of cormlets and vigorous growth. 'Shiny Lemon' could be cultured under greenhouse conditions in Korea.

• Korean Journal of Breeding Science
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• v.43 no.3
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• pp.210-213
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• 2011

A dark pink semi-double freesia (Freesia hybrida Hort.) 'Happy Birthday' was bred from a cross between 'Pink Jewel', F1 progeny of 'Michelle' and 'Rossini' as a female and 'White Lace' as a male parent. Test for the growth vigor and flowering characteristic were conducted from 2002 to 2007. A new variety 'Happy Birthday' has semi-double flower type with dark pink color (RHS color chart #RP66C). It has multiple flowers, distinctive flower shape, upright leaves and also stalks. The average yield of this variety 'Happy Birthday' counted over 6.7 stems per plant per season in the standard greenhouse cultivation method. It has also good production of cormlets, vigorous growth. A new variety 'Happy Birthday' is suitable for the greenhouse conditions during winter season in Korea.

• Korean Journal of Breeding Science
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• v.42 no.6
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• pp.699-702
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• 2010

Anthracnose is a major limiting factor of the watermelon production in Korea. A mid-late maturing watermelon line, 'Hanbit' with resistance to anthracnose (Colletotrichum orbiculare) race 1 and 3, was developed by the cross between anthracnose resistant cultivar 'AU-Producer' and high quality inbred line '920533' at the National Institute of Horticultural and Herbal Science, Rural Development Administration (RDA). 'Hanbit' produces 5.4 to 9.5 kg of red flesh fruits with clear stripes on skin. Average soluble solid contents are ranged from 10.4 to 11.2$^{\circ}$Bx. The yield and quality of 'Hanbit' was comparable to or better than those harvested from the popular commercial cultivars. 'Hanbit' can be cultivated in open fields and under the protected green house condition. In addition to the commercial production, it can be used as a resistant material in $F_1$ hybrid breeding program.

• Korean Journal of Breeding Science
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• v.50 no.4
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• pp.510-515
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• 2018

Hwangmichal, a yellow waxy corn hybrid, is a single cross hybrid developed in 2014. This hybrid was created by crossing the seed parent KY30 and pollen parent KY9. Hwangmichal has yellow kernels with a conico-cylindrical ear shape. The days to silking of Hwangmichal were similar to that of Ilmichal, a check hybrid. The ear height ratio of Hwangmichal was 50%, which was lower than that of Ilmichal, and its number of tillers was less than that of Ilmichal. The ear size of Hwangmichal was smaller than that of Ilmichal and the kernel set ratio was 89%. Its sensory evaluation was better than that of Ilmichal. The carotenoid content of Hwangmichal was $32.2{\mu}g/g$, which was much higher than that of Ilmichal. Lodging resistance of Hwangmichal was better than that of Ilmichal. Although the number of fresh ears of Hwangmichal was more than that of Ilmichal, the weight of fresh ears was lower than that of Ilmichal. The flowering period of its parent lines was well matched and seed production was 3:1 at a planting density of parent lines of more than 2:1. It is adaptable to the whole country except for Jeju-do. The plant variety protection right of Hwangmichal was registered in June 2017, and its grant number is 6728.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.5
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• pp.60-67
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• 2019

In general, a reinforced concrete slabs are known to have a high fire resistance performance due to thermal properties of concrete materials. However, according to previous research, the thermal behavior of voided slabs is reported to be different from that of conventional RC solid slabs, and the differences seem to be caused by the air layer formed inside the voided slab. Therefore, it is difficult to estimate the temperature distribution of the voided slab under fire by using the existing methods that do not take into account the air layer inside the voided slab. In this study, a numerical analysis model was proposed to estimate the temperature distribution of voided slabs under fire, and evaluated. Heat transfer of slabs under fire is generally caused by conduction, convection and radiation, and time-dependent temperature changes of slab can be determined considering these phenomena. This study proposed a numerical method to estimate the temperature distribution of voided slabs under fire based on a finite difference method in which a cross-section of the slab is divided into a number of layers. This method is also developed to allow consideration of heat transfer through convection and radiation in air layer inside of slabs. In addition, the proposed model was also validated by comparison with the experimental results, and the results showed that the proposed model appropriately predicts the temperature distribution of voided slabs under fire.