• Journal of Animal Science and Technology
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• v.46 no.5
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• pp.735-742
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• 2004

This study was conducted for the identification of pure Landrace, Large White and Duroc breeds which are mainly maintained in Korea using DNA markers. We used known KIT and MC1R mutations, which were related coat color in pigs, and pig mitochondrial DNA variations. The KIT mutation was used to distinguish white and colored animals. Duroc breed could be discriminated from other colored breeds using the MC1R mutation N121D. Discriminating Landrace and Large White was possible using the l l-bp duplication of D-Ioop region and alternative initiation codon of ND2. In conclusion, identification of Landrace, Large White and Duroc breeds was might be possible using the procedure designed in this study.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.10a
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• pp.7-8
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• 2006

• FLOWER RESEARCH JOURNAL
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• v.16 no.4
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• pp.295-298
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• 2008

A new Cymbidium cultivar 'White Princess' was released by the National Horticultural Research Institute (NHRI) in 2005. A cross was made in 1995 between 'Cymbidium 2113', light purple colored petal and medium plant sized variety, and 'Lucky Rainbow Randevous', a dark purple petal with red lip and large type variety. The ninety progenies were obtained after planting and acclimatization in green house. In 2000, a line (9526747) was selected and multipliticed after test of its flower color, leaf shape, flower stalk, and vigorous growing habit. After evaluation trial for two growing seasons, the selected line was named as 'White Princess'. The 'White Princess' has white petals (WN 155A) with red lip (RP59D) color and large sized leaves, and flowers (leaf length is about 88 cm and flower diameter is about 8 cm) with semi-erect flower stalks. Blooming started from December to January in optimal culture conditions. High temperature (more than $30^{\circ}C$) and low light intensity(less than 10,000Lux) should be avoided for the appropriate growth.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.5
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• pp.480-488
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• 1994

Low seedling growth rates of white clover (Trifolium repens L.) have been limited its good establishment to pastures. The experiment was done to determine the effect of removal of cotyledon and unifoliolate on the growth and morphological characters of contrasting white clover cultivars for 8 weeks after the treatment. Individual plants of cv. Regal (large leaf), Louisiana S-l (medium-large leaf), Grasslands Huia (medium-small leaf) and Aberystwyth S184 (small leaf) were grown in 10cm plastic pot containing a 2:1:1 soil:sand:peat moss mixture until the cotyledon or unifoliolate stage and then removed one (C1) or two cotyledons (C2) at cotyledon stage, and unifoliolate only (U), unifoliolate and one cotyledon (DC1) or unifoliolate and two cotyledons (DC2) at the unifoliolate stage. To measure the removal effect on biomass and morphological characters (leaf area, petiole and stolon lengths, growing tips and leaves), plants were sampled 4, 6 and 8 weeks after the treatment. Intact plants had greater biomass and morphological characters than removal-treated ones, Removal treatments at cotyledon stage, C1 and C2, were decreased more biomass and morphological characters than removal ones at unifoliolate stage while the severer cotyledon removal, the more reduction. Stolon length per plant and petiole length markedly inclined 6 weeks after the treatments although biomass and the other characters continuously did. Relatively large-leaved cultivar had more biomass, leaf area per plant and longer petiole than the other(s) but the reverse results were true in stolon length, growing tips and no. of leaves per plant. Biomass was linearly increased with increased leaf area but the earlier and severer removal, the less slope. The severer damage of cotyledon and unifoliolate had detrimental effects on the growth and aftermath establishment of white clover

• Journal of Environmental Impact Assessment
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• v.18 no.5
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• pp.293-299
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• 2009

Wintering migratory species of white-fronted geese (Anser albifrons) are common visitor in South Korea, and this study examined the survivorship of white-fronted geese in the Junam Reservoir with the application of Population Viability Analysis (PVA) technique. In Junam PVA analysis was done for the next 50 years using factors of breeding population, sex ratios, survivorship in the VORTEX program. As a result white-fronted geese will reach to carrying capacity within 40 years, and population will reach to carrying capacity later when it becomes smaller. Also with a large initial population white-fronted geese will reach to carrying capacity earlier. In conclusion, for the next 50 years the white-fronted geese are expected to a long-term survival with stable condition with survivorship (0.03) and extinction rate (0.0).

• Journal of Life Science
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• v.11 no.1
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• pp.54-61
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• 2001

The comparative morphology of epididymal spermatozoa in the lesser white-toothed shrew, Crocidura suaveolens, the Japanese white-toothed shrew, C. dsinezumi and the big white-toothed shrew, C. lasiura, belonging to the subfamily Crocidurinae was studied with the light and electron microscopes. The spermatozoa of C. lasiura and C. dsinezumi were characterized by the large acrosome, serrated inner acrosomal membrane, common apical body and fistulous proximal centriole with slightly dense electron granular materials, which are the charateristics of the Crocidurinae. The C. suaveolens, however, is distinguished from the two species mentioned above in the sperm morphology. That is, the spermatozoa possess not only the charateristic of the Crocidurinae such aw the large acrosome, but also those of the Soricinae, i.e. the smooth inner acrosomal membrane, wavy, finger-like and electron-dense apical body, and the solid proximal centriole filled with electron-dense materials. The results suggest that C. suaveolens has conserved characteristics of the Soricinae.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.5 s.170
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• pp.21-27
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• 2005

• Korean Journal of Animal Reproduction
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• v.12 no.1
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• pp.15-19
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• 1988

This study was carried out to investigate the fertility and farrowing date in post-weaning sows using PG600 and inseminated with frozen semen. A total of 48 sows of Landrace, Large White and Duroc after 7-week lactation were used at the Chungnam Provincial Animal Breeding Station. The results obtained were summarized as follows: 1. Motility had no significant differences between the breeds, but NAR acrosome was highest in Landrace, followed by Duroc and Large White(p<.01). 2. Interval from weaning to estrus and length of estrus were, respectively, 3.7 days and 52.6hours of sows treated with PG600, and 6.5 days and 53.8 hours for control sows. The average interval from weaning to onset of estrus was significantly(p<.01) shorter by 2.8 days in PG600 treated sows compared to control sows. 3. In Landrace, Duroc and Large White, farrowing rate and number of pigs born alive per litter were 55.0%, 10.0; 43.8%, 8.1; and 16.7%, 3.5, respectively. Average pig weight at birth and survival rate at 56 days had no significant differences between the breeds. 4. Farrowing rate, number of pigs born alive per litter, average pig weight at birth and survival rate at 56 days were, respectivey, 45.8%, 101, 1.56kg and 94.5% for sows treated with PG600, and 37.5%, 7.0, 1.66kg and 93.8% for control sows. Sows treated with PG 600 had an average of 3.1 more pigs at farrowing compared to control sows.

• Journal of Advanced Marine Engineering and Technology
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• v.19 no.4
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• pp.61-71
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• 1995

Nowadays the thin-walled metal bearing, which is made seperately from the bearing housing and has the ratio of wall thickness/bearing diameter being less than 1/30, are used in many newly developed large-sized slow speed diesel engines for the purpose of upgarding lubication performance and easy maintenance according to the trends of increasing output per cylinder and lowering engine speed. The type of this bearing has been used generally in many small-sized high speed engines applied for automobile, high speed craft and industrial power generation systems since 1950s. But the tranditional thick-walled bearings, whice are linned white metal on the bearing housing directly, have been installed on the large and slow speed engines until 1990s due to the easy manufacturing procedures. In this study we have calculated optimum dimensions of the metal bearing, fabricated special zigs for crush measurement, model test machine, 2 sets of specimens.(crosshead pin bearing, $\phi$818*552*20mm) for B & W 6S70MC(20, 940*88rpm), and evaluated metal constact phenomena of white metal, its friction coefficient, temparature rise through the model test and field performance test.

• Animal Systematics, Evolution and Diversity
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• v.31 no.2
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• pp.122-127
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• 2015

The subfamily Ennominae is one of the most species-rich taxa of Geometridae that include more than 9,700 species worldwide and over 280 species in South Korea. Herein, we present the first report of five species of Ennominae. Abraxas flavisinuata can be characterized by the white wings, a thick black postmedial line that is medially and dorsally broken with an orange band, large rounded black discal dots on the forewing, and a black dotted postmedial line on the hindwing. Lomographa claripennis can be characterized by the whitish wings, the black undulating postmedial line as well as the minute blackish discal dot on the forewing, and the black undulating postmedial line with a minute black discal dot on the hindwing. Arichanna tetrica can be characterized by the grayish forewings, thick black transverse ante- and postmedial lines, a large blackish discal dot, whitish apical streak on the forewing, and scattered black dots on the whitish hindwing. Apocleora rimosa can be characterized by the brown ground color of the fore- and hindwings, the black slanted ante- and postmedial lines of the forewing, and two black medial lines on the hindwing. Ourapteryx japonica can be characterized by the white wings, the dark brown transverse ante- and postmedial lines with a long discal dot on the forewing, and the dark brownish transverse antemedial line as well as a termen that has a sharp white tail with one large dark reddish dot and one small black dot on the hindwing.