• The Korean Journal of Ecology
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• v.13 no.3
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• pp.225-236
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• 1990

We studied that seeds of wild radish with different size of weight can be obtained for the purpose of differentiation and growth of these seeds by total growth periods. This study is practised a view of plant eco-physiological side and dry-matter production. Through whole growth periods, we knowthat seed weight of L plots was higher than that of M and S plots. In the 33th day after day after germination, growth values of L, M and S plots were 13.93, 7.77, and 4.61 g/plant, respectively. Growth of shoot (cotyledon and leaf) area and shoot weight were shown the similar trends with individual plant dry-amtter weight. In the 33th day after germination, shoot area of L, M and S plots were 21.55, 11.81 and 8.75 $cm^3$/plant and shoot dry weight of L, M and S plots were 10.83, 6.03, 3.50 g/plant, respectively. In the early stage of growth (the 10-14th day after germination), the values of RGR of seed weight of L, M, S plots were 0.2887, 0.2807 and 0.2365 g/g/day, in the late stage of growth, those values of RGR of L, M, S plote were 0.2721, 0.1716, 0.1727 g/g/day, respectively. In the early stage of growth (the 14th day after germination), the values of NAR or L, M and S plots were 0.1513, 0.1373, and 0.1094 g/$cm^2$/day, respectively. It is thought that seed weights were influenced seriously effect in the early stage of growth. The NAR value, in the late stage of growth (the-28-33th day after germination), of L, M and S plots were not large different as 0.1086, 0.1097 and 0.112 g/$cm^2$/day, respectively. The LAR values of M and S (2.0396, 2.1520 $m^2$/g) plots, in the early stage of growth, were higher than L (1.9037 $m^2$/g) plots. In the late stage of growth, the value of LAR of L plots were nearly same as M plots, but the value of S plots were higher than that of L and M plots (0.0458 $m^2$/g). And, in the early stage of growth, the values of SLA of L, M and S plots were 2.2123, 2.2107 and 2.8448 $m^2$/g, respectively. We measured the photosynthetic rates and the respiratory rates as the physiological characteristics of wild radish. In the early stage of growth, the photosynthetic rates of L, M and S plots were 12.4, 14.4, 9.8 $\mu$mol /$m^2$/sec and 9.4, 11.4, 9.8 $\mu$mol/$m^2$ /sec in the late stage of growth, respectively. In this result, it could be informed that photosynthetic rates in the late stage of growth were lower than the early stage. In the middle stage of growth, the respiratory rates were 0.793, $\mu$mol/$m^2$/min in shoot, and 3.28 $\mu$mol/$m^2$/min in root without relation to seed weight. The growth analysis of plants was used by Hunt & Parson s computer program (1974, 1981) and its results used this program were good. Therefore, in this sense, it could be expected that the computer program used and developed largely in researches of plant growth.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.1
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• pp.92-97
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• 1995

The objective of this study is to investigate the growth characters of overhead flooded soybean plants at four growth stage. Overhead flooding treatments were applied at the vegetative growth stage ($V_3,\;V_6$) and the reproductive stage ($R_2,\;R_4$) for 6.12.24 hrs, respectively. Yield and yield components were more decreased as the overhead flooding duration was longer and the growth stage was later. Yield was not reduced significantly in soybean plants flooded at $V_3$ stage regardless of flooding duration, and flooded 6 or 12 hrs at $V_6$ stage. When compared to the control, 27 to 36% of yield reduction was observed in soybean plants flooded for 24 hrs at $V_6$ stage, 6 or 12 hrs at $R_2$ stage, and 6 hrs at $R_4$ stage. And 43%, 53% and 66% of yield were reduced through the flooding treatment for 24 hrs at $R_2$ stage 12 hrs and 24 hrs at $R_4$ stage, respectively. So yield reduction was higher in overhead flooded soybean plants at the reproductive stage than that at the vegetative growth stage.

• Korean Journal of Weed Science
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• v.30 no.4
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• pp.371-379
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• 2010

Crimson clover (Trifolium incarnatum), hairy vetch (Vicia villosa) and rye (Secale cereale) are common leguminous cover crops. Because they contain water-soluble allelopathic substances that show a variable level in tissue depending on growth stage of the plants, the weed inhibition effects are dependent on the growth stage of cover crops. This study investigated the allelopathic effects of crimson clover, hairy vetch and rye on soybean, radish, oilseed rape and lettuce seeds germination and seedling growth. We used extract that were prepared from the shoots of crimson clover, hairy vetch and rye at different growth stages, vegetative growth stage, flowering stage, and fruiting stage. Applications of aqueous extracts from three growth stage of cover crops strongly affected to oilseed rape and lettuce seeds germination but the treatment resulted in a slight inhibition of the germination in soybean and radish. Radical length was more sensitive to aqueous extracts than seed germination rate. Especially, three cover crops extracts at vegetative growth stage highly inhibited seedling root growth of oilseed rape and lettuce by over 80% and 90% respectively. Furthermore, the $GR_{50}$ values were lowest in the treatment of extracts from vegetative growth stage and the level of phenolics was decreased by the order of vegetative growth stage, flowering stage and fruiting stage.

• The korean journal of orthodontics
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• v.19 no.3
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• pp.99-111
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• 1989

To study the sexual maturity at puberty and interrelation between pubertal growth peak and sexual maturity, 68 malocclusions (female 44, male 24) were longitudinally studied for 4 years and cross-sectional samples of 210 malocclusions were studied together. The pubertal growth peak was determined by stature increment and sexual maturity was studied using developmental stages of pubic hair and breast, menarche in female and those of pubic hair in male. The following results were obtained. 1. Mean age at menarche was 12.8 years and it was 11.8 months later than PHV. 2. At pubertal growth peak, developmental stage 2 (54.2%) and 3 (29.2%) of pubic hair were most in male, and stage 1 (72.7%) and 2 (20.5%) were most in female. 3. At pubertal growth peak, the developmental stage 2 (50%) of breast was most and the stage 3 (43.2%) was next. 4. In interrelation between skeletal growth and sexual maturity, PHV had most high correlation with menarche and stage 3 of breast, and menarche had most high correlation with stage 3 of breast. 5. Appearance of remarkable sexual maturity suggested that the PHV was passed already.

• Journal of Aquaculture
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• v.17 no.3
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• pp.221-227
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• 2004

In the present study, we investigated the effects of food and salinity on growth and survival of river puffer, Takifugu obscurus offsprings in indoor land-based tank during the early development. In the food experiment, the river puffer larvae (TL 8.7$\pm$0.1 mm, BW 20.0$\pm$3.2 mg) were fed with tubificid, Limnodrilus gotoi, water flea, Daphnia carinata, mysid, Neomysis awatschensis, Manila clam, Ruditapes philippinarum and artificial food together Artemia nauplii for 30 days, and the growth and the survival of larvae were investigated. In the salinity experiment, the river puffer larvae and juvenile at three stages (Stage I: TL 5.8$\pm$0.4 mm; Stage II: TL 12.0$\pm$0.2 mm, Stage III： TL 44.5$\pm$0.7 mm) were supplied with Artemia nauplii, water flea and/or artificial food and were reared in 0, 10, 20 and 30 psu at respective stages. The results shows that the growth rates of larvae feeding with artificial food and tubificid together Artemia nauplii were higher than those of larvae in other groups, but the survival rates of larvae feeding with water flea and mysid together Artemia nauplii were higher than those of larvae in other groups. In salinity, the results shows that the growth and survival rates of offsprings were significantly higher in 10∼20 psu than those in 0 and 30 psu at Stage I and n. At Stage III, the growth and the survival rates were the highest in 20 psu, but the lowest in 0 psu. However, it should be noted that the rates in 0 and 30 psu were significantly enhanced at Stage III in comparison with those at Stage I and II. Therefore, it is concluded that river puffer, T. obscurus is euryhaline marine species, which can normally grow and live at salinities from 0 to 30 psu, and that a combinative supplement with Artemia nauplii and water flea, D. carinata may confer an advantage on growth and survival of the river puffer offsprings in indoor land-based tank.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.2
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• pp.143-148
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• 1999

Soil moisture condition is an important limiting factor in growth and yield in rice culture. The purpose of this study was to compare the influence on the growth, yield and Quality of rice subjected to soil moisture stress (SMS) at different growth stages. Ajaponica rice cultivar, Dongjinbyeo, was cultured under flooded conditions in a plastic container filled with silty loam soil. The container was subjected to SMS until the initial wilting point (IWP) coincided with about 10% in soil moisture content and about-200 kPa in soil matric potential, and was then irrigated again, at 6 and 5 of main growth stage in 1996 and 1997, respectively. At maturity, the plant height, tiller number, leaf area and top dry weight were decreased more in SMS treatments at the early stage than the late stage. The averaged yield index of SMS to control in both years was lowest at meiosis (62.5%), which primarily resulted from lower percent ripened grain and 1,000 grain weight, and second＇ reduced the spikelet number per panicle and panicle number per hill, and followed at tillering stage (68.5%) which resulted from the lower production in tiller number and top dry matter during and after SMS treatment. The percent-age of read rice in SMS plants varied with the treatment stage as order of lower at meiosis (44.0%), heading (53.9%), panicle initiation (70.1%), tillering (72.1%), ripening (75.8%) and 5 days after transplanting (DAT) (79.0%). Protein content in brown rice was slightly larger in SMS at late growth stage than the control, while the contents of fat and ash differed very little between SMS and control. Contents of Mg and K and Mg/K in brown rice with SMS were lower at some treatment stages such as at ripening or panicle initiation.

• Membrane and Water Treatment
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• v.15 no.1
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• pp.11-19
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• 2024

This study presents the characteristics of growth and morphology of Anabaena sp., a representative filamentous cyanobacterium, depending on temperature variation from 10 to 30 ℃. Both the filament density (or number) and its length of Anabaena were highly affected by temperature, as well as growth stage. Rapid growth at a higher temperature led to an increase in Anabaena filament density, as well as optical density at 680 nm (OD₆₈₀). However, the number of vegetative cells within a single filament of Anabaena grown at 30 ℃ was smaller than those grown at lower temperatures, due to the intercalary division of the filament. Of the three different cells comprising a single Anabaena filament, the vegetative cell marginally affects the growth of Anabaena. The main dimensions of the vegetative cell, i.e., length and width, depend on the temperature and growth stage. The length-to-width (L/W) ratios of vegetative cells and akinetes were relatively consistent regardless of the temperature. However, in vegetative cells with dichotomous growth, the L/W ratio shows clear differences depending on their growth stage. It has been demonstrated that the L/W ratio could be used as an indicator to indirectly predict the growth stage of on-sit Anabaena samples.

• Horticultural Science & Technology
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• v.16 no.2
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• pp.247-250
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• 1998

This study was carried out to investigate the effects of changes of ionic strength according to growth stage on growth and flowering of Dendranthema grandiflorum (Ramat.) Kitamura 'Seiun' grown hydroponically in perlite. The stage I, II, and III covered early vegetative growth (27-40 days after planting), latter vegetative growth (41-54 days), and reproductive growth (55-80 days), respectively. The 2 strength (1S and 2S) of nutrient solution were treated in stage I, whereas 3 strengths (1S, 1-2S, and 2S) were treated in stage II. Then, total 9 treatments in stage III were designated by 3 treatments (tap water, 1S, and 2S) for each 3 strengths in stage II. Each nutrient solution was applied 8 times per day. At vegetative growth stage (54 days after planting), stem length was highest when irrigated 8 times a day with 1S nutrient solution. Both photosynthesis and transpiration rate were higher in 1S than those in other treatments (1-2S, 2S), whereas leaf chlorophyll content was highest in 2S treatment. Ion content of plant treated with 2S was higher than other treatments. Growth (plant height, leaf area, stem length), fresh weight, and dry weight of each plant organ after flower bud formation were better in tap water treatment (1-1-0) than other 1S treatments (1-1-1, 1-1-2). Regarding the number of days to flowering, tap water treatment was the most effective. Thus, after flower bud formation supplying tap water or lower concentration of nutrient solution than those used during the vegetative growth stage was economical in saving chemical fertilizers, shortening the number of days to flowering, reducing salt accumulation in media, saving efforts of leaching, and reducing ground water contamination.

• Journal of Korea Society of Digital Industry and Information Management
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• v.17 no.4
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• pp.177-195
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• 2021

The purpose of this study is to examine the trouble of recruitment and research and development of ICT SMEs. Recently, many ICT SMEs have emerged for selling products and services using the technology of the 4th industrial revolution. However, SMEs have relatively deficient resources compared to large companies, the difficulty of maintenance or growth of human resources and intangible resources. This research methodology organized the four stages of the analysis process. The first analysis is the association rules for human resource recruitment. The second analysis is the difficulty of hiring jobs and experienced workers by each stage of company growth. The third analysis is a regression analysis of the trouble of R&D activity. The last analysis is an analysis of association rules on the difficulties of management activities by company growth. As the research result, the first analysis has shown a difference in favored human resources by the ICT industry. The second analysis also showed factor differences in job recruitment difficulties for each stage of corporate growth. In the third analysis, the operation of research institutes in ICT SMEs is influenced by industry type, corporate certification, corporate growth stage, self-technology development, joint technology development, technology transfer, and commercialization. As the last analysis, ICT SMEs showed factor differences in difficulties in management activities by stage of corporate growth. This study contributed empirically emphasizing the troubling phenomenon of human resources and R&D necessary for the growth of ICT SMEs. As a theoretical implication, this research contributed to the research-area expansion of management information using big-data technologies. In particular, this research practically suggests the differentiated direction of recruitment and R&D by ICT SMEs based on industry and each stage of company growth through the association rules of big data.

• Korean Journal of Pharmacognosy
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• v.27 no.1
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• pp.32-36
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• 1996

Various culture conditions for cell growth and berberine production in cork tree (Phellodendron amurense Rupr.) were investigated. Callus was induced from cambium tissue of cork tree, and cultured on LS liquid medium supplemented with 0.5 mg/1 2,4-D, 0.1mg/1 BA, and 3% sucrose. Several factors enhancing berberine production and cell growth in cork tree cell cultures were found. Some of them enhanced both cell growth and berberine production, but others resulted in a decoupling of cell growth and berberine production with significant in the specific levels. High level of nitrate (80mM), high level of phosphate (8.98mM), and sucrose (7%), 1.0mg/l IAA were effective in berberine production, whereas low level of nitrate (40mM), and phosphate (2.25mM), and high level of sucrose (7%) in the medium were effective in cell growth. Two stage culture(first stage for cell growth, and second stage for berberine production) increased berberine production almost twice (5.06mg/g dry weight) as much as single stage cultures in berberine production.