• Journal of the Korean Institute of Landscape Architecture
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• v.32 no.2
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• pp.120-129
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• 2004

This study was carried out to develop new varieties with early maturing and large fruit size in the Korean native dogwood (Cornus kousa) for woody landscape plants from native sites or cultivated area. The results are obtained as follows; We selected strains with early maturing and large fruit. size from the habitats from 2000 to 2003. ‘SKK 2-1’ had 4.0cm of fruit size while 2.0 cm of native variety. In addition, ‘SKK 2-2’, ‘SKK 2-3’, ‘SKK 2-4’, and ‘SKK 2-5’ with large fruit and early maturing were preliminary selected from the habitats. In the preliminary selections, ‘SKK 2-1’ was finally selected as new early maturing variety with large fruits in 2003. New early maturing variety with large fruit size, C. kousa var. ‘SKK 2-1’ was selected from 200 plants of 5-year-old seedlings in C. kousa in 5-12 Nung wean ri Goo sung myun Yong In, Kyung gi do, Korea in 2000. Their fruits were colorized in September 18, 20∼25 days earlier than October 7 of native varieties. Its fruit diameter is larger than 4cm. Its fruit weight was 5 times as heavy as native cultivars grown in Korea. This useful characters were still inherited after grafting. However, characteristics of growth, leaf, flower, and flowering period were not different from those of native varieties. Therefore, it was very promising landscape woody plant, having large fruits in early fall season. The rooting rate of Korean dogwood was high by the IBA treatment. The optimum date for softwood cutting was on June 25 ∼ July 25 when the rooting rate was more than 80%. In addition. Korean dogwood was easily propagated by grafting. Therefore, new early maturing variety with large fruits, C. kousa var. ‘SKK 2-1’ is easily propagated by softwood cutting or grafting and then is a promising cultivar as a woody landscape plant.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2002.11a
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• pp.51-54
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• 2002

This study is intended to investigate an influence of the kinds and the maximum size of aggregate on the compressive strength of small size core specimen. According to the results, the compressive strength of standard specimen is large in order of basalt, granite and limestone aggregate, and shows increasing tendency as the maximum size of aggregate grows large. The compressive strength of concrete using basalt aggregate shows similar tendency to granite aggregate, and that of concrete using limestone aggregate decreases slightly, compared with granite aggregate. The reducing ratio of the compressive strength of 25mm core specimen is least when the maximum size of aggregate is 10mm. But the compressive strength of 50 and 100mm core specimen is almost not influenced by the maximum size of aggregate.

• Korean Journal of Metals and Materials
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• v.48 no.9
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• pp.847-855
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• 2010

The grain size of a cross-section of $8{\mu}m$-thick copper film was determined by electron backscatter diffraction analysis. Grain size distribution histogram showed the presence of a large fraction of small-sized grains, and the mean grain size was significantly affected by handling of them. A cut-off grain size, below which all grains are ignored as noise and eliminated for the calculation of the mean value, should be three or four times as large as the step size. Due to the presence of small grains, the linear intercept method derived larger mean grain size, which depends less sensitively on the cut-off grain size than the equivalent circle diameter method.

• Korean Chemical Engineering Research
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• v.50 no.2
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• pp.304-309
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• 2012

Size verification of small and large bubbles in a bubble column was investigated by employing the dynamic gas disengagement (DGD) method and dual electrical resistivity probe (DRP) method, simultancously. The holdups of large and small bubbles in the bubble column in a given operating condition were obtained by means of the DGD method by measuring the pressure drop variation in the column with a variation of time after stopping the gas input into the column. The size and frequency of bubbles were measured by the DRP method in the same operating condition, from which the bubble holdup of each range of size was obtained. The verification of size in determining the large or small bubbles was decided by comparing the holdups of large or small bubbles measured by the DGD method with that measured by the DRP method. Filtered compressed air and tap water were used as a gas and a continuous liquid medium. The diameter and height of the bubble column were 0.102 m and 1.5 m, respectively. The demarcation size between the large and the small bubbles in the bubble column was 4.0~5.0 mm; the demarcation size was about 5.0 mm when the gas velocity was in the relatively low range, but about 4.0 mm when the gas velocity was in the relatively high range, within this experimental conditions.

• Journal of Ecology and Environment
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• v.44 no.3
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• pp.143-154
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• 2020

Background: Korean wild boars (Sus scrofa coreanus Heude), because of their adaptability, are a widespread large mammal; however, they sometimes cause problems by invading farms and eating the crops, creating insufficiencies of some foods in South Korea. To understand the diet composition of Korean wild boars according to sex and body size, we collected their feces from Mt. Jeombongsan, Seoraksan National Park, South Korea. The sizes of fecal samples were measured, and genomic DNA was extracted from the samples. We amplified specific loci targeting plants (rbcL and trnL) and animals (COI) to detect the food sources of this omnivore and amplified the ZF and SRY regions to determine the sex. Results: In the wild boar feces, Rosaceae and Bryophyte were the most frequently detected plant food sources at the family level and Diptera and Haplotaxida were the most frequently detected animal food sources at the order level. As a result of sex determination, the sex ratio of wild boars collected in the Mt. Jeombongsan area was approximately 1:1. Our result suggested that there is no significant difference between the diet composition of male and female boars. Based on the average cross-sectional area of the feces, the top 25% were classified into the large body size group and the bottom 25% were classified into the small body size group. The large body size group mainly preferred Actinidiaceae, and the small body size group most frequently consumed Fagaceae. The diet of the large body size group was more diverse than the small body size group. Conclusions: Our results showed that the wild boars preferred Rosaceae, especially Sanguisorba and Filipendula, as plant food sources, and Diptera and Coleoptera of Insecta as animal food sources. Based on the results, the dietary preferences of wild boar appear to be distinguished by not their sex but their body size. Our study could help to elucidate the feeding ecology and population structure of wild boar, as well as address conservation and management issues.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.3
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• pp.152-155
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• 2003

Burcucumber (Sicyos angulatus L.), used as a medicinal or rootstock for cucurbitaceous crops have shown high variation in seed maturity and size. This study was carried out to determine the effect of seed maturity and size on seed germination, seedling emergence and growth of burcucumber, Seeds collected from a native site were divided into small, medium and large ones after sorted to mature and immature ones. Their germination, seedling emergence and growth were done in indoor and a green house. Mature seeds showed higher germination and seedling emergence rate than immature ones. Regardless of their maturity, medium. and small seeds showed higher germination rate than large ones. Medium and large seeds, however, had the greatest and the least seedling emergence, respectively. Seedling height, number of true leaves areas of cotyledons and true leaves except hypocotyl length were increased with increased seed size although were not affected by the maturity. Cotyledon, leaf, hypocotyl, root and their total dry weights were greater in large mature seeds than large immature ones while increased with increased seed size in both maturities.

• Journal of The Korean Association For Science Education
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• v.4 no.1
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• pp.15-25
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• 1984

The purpose of this study is to develop a practical and ideal model of science laboratory enrolled 48-60 students by studying optimal facilities such as laboratory tables and chairs proper to elementary school settings. The science laboratory model was figured out in terms of the following six procedures; (1) Current status as well as problems of science laboratory and its facilities was identified by means of the questionnaires conducted to 201 elementary schools, using stratified cluster sampling tehnique, under the consideration of the school size and the regional characteristics across the country. (2) Collected were the anthropometric data with respect to sitting height, popliteal height, buttock popliteal length, elbow rest height, and back width from the 747 students, 4th-6th grade, in Seoul area. (3) It was measured the work apace necessary for individual student to perform his experiment. (4) Using the data of the process (2), we determined the optimal sizes of laboratory tables and chairs fitted for Korean elementary school students. (5) The optimal area of science laboratory for 48-60 students is determined in terms of the data obtained in (3) for individual work space in addition to the appropriate table size figured out by (4). (6) A practical and ideal model for a science laboratory in elementary school was designed according to the above procedures. For the optimal model of science laboratory, the results of this study can be summarized as follows: The sizes of chair and table are categorized into three groups such as small, medium, and large depending on students' physical outfit. The small size base on the 12.5th percentile point of students' sitting height is used for students of the 0-25th percentile ranks. The medium size base on the 50th percentile point of students' sitting height is used for students of the 26-75th percentile ranks. The large size base on the 87.5th percentile point of students' sitting height is used for students of the 76-100th percentile ranks. (1) Sizes of chairs: The small size is 28cm in width and 33cm in height. The medium size is 31cm in width and 36cm in height. The large size is 35cm in width and 38cm in height. (2) Sizes of laboratory tables: The small size is 120cm in length, 86cm in width, and 60cm in height. The large size is 120cm in length, 86cm in width, and 60cm in height. The large size is 120cm in length, 86cm in width, and 65cm in height. (3) Size of science laboratory: The optimal science laboratory for 48-60 elementary school students, which can install the 12 laboratory tables, is 12m in length and 10m in width.

• Korean Journal of Child Studies
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• v.22 no.4
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• pp.201-212
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• 2001

The purpose of this study was to analyze toddlers' verbal and nonverbal interaction with their peers and caregivers according to the class size of child care centers in Seoul. The subjects of this study were 20, two-year-old(M=32.5 month) toddlers with peers and caregivers from child care centers in different class sizes, but with same caregiver-toddler ratio. Verbal and nonverbal interactions were videotaped during one hour indoor free play per child in the center. According to the class size, the results were as follows : 1) Toddlers in the small class played more cooperatively with peers, and uttered more regulative or directive words than those in the large class. 2) Toddlers in the large class were more aggressive than those in the small class. 3) Caregivers in small class expressed more empathetic behaviors to a toddler than those in large class.

• Journal of the Korean Society of Clothing and Textiles
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• v.29 no.1 s.139
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• pp.68-78
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• 2005

The purpose of this study was to examine the women consumers' clothing consumption value and involvement according to size of the city. 538 females living in Seoul(large city) and Jecheon(small city) were surveyed for this study. For data analysis, factor analysis, t-test, and regression were used. For clothing consumption value, five factors of value were founded and labeled as functional, emotional, epistemic, social and conditional value. Three factors of clothing involvement were also identified as clothing/fashion, symbolism and reasonability involvement. Size of the city influenced total clothing consumption value and involvement. Also, size of the city influenced clothing consumption value and involvement factors. When the cities were divided into two groups(large and small city), they showed different clothing consumption values and involvements according to the demographic variables.

• Journal of the Korean Ceramic Society
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• v.50 no.6
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• pp.528-532
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• 2013

Well-dispersed slurries of submicron-sized alumina powders were pressure-infiltrated in 3D preforms of mullite fibers and the effects of the particle size and infiltration pressure on the particle packing characteristics were investigated. Infiltration without pressure showed that the packing density increased as the particle size decreased due to the reduction of the friction between the particles and the fibers. The infiltrated preforms contained large pores in the large voids between the fiber tows and small pores in the narrow voids between the individual fibers. Pressure infiltration resulted in a packing density of 77% regardless of the particle size or the infiltration pressure(210 ~ 620 kPa). Pressure infiltration shortened the infiltration time and eliminated the large pores in preforms infiltrated with the slurries of smaller particles. The slurry pressure-infiltration process is thus an efficient method for the packing of matrix materials in various preforms.