• Korean Journal of Plant Resources
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• v.34 no.6
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• pp.608-615
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• 2021

Soil moisture control system including soil sensing and automatic water supply chain was constructed on open farmland and pot conditions. Soil moisture was controlled by the system showing over the soil moisture contents except 40% treatment. EC was gradually decreased by increasing cultivation days. On applying this system to control soil moisture, the growth and development characters of the bellflower were improved compared with control, cultivation without the automatic irrigation. Of the growth and development characters, plant height with water treatments was higher than that of control in 1st-year plants. Moreover, numbers of branch were increased by the increased soil moisture on farmland and pot condition. Capsule numbers for seed were best at 20%, 30% soil moisture treatment in 1st-year plants, and 20% to 50% treatment in 2nd-year plants. The construction of automatic soil moisture control system provide fundamental data for plant growth and development on open farmland soil condition.

• Korean Journal of Environmental Biology
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• v.30 no.2
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• pp.107-120
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• 2012

This study was carried out to illiminate the diversity of vascular plants by making list of rheophyte and hydorphyte plants at Yugu stream. This study was conducted from Aug., 2009 to Sept. 2010 at 7 points. Based on the voucher specimens, vascular plants from investigated areas were 88 families 229 genera 290 species 3 subspecies 30 varieties 5 forms, totally 328 taxa. Korean endemic plants were 3 species such as Forsythia koreana (Rehder) Nakai (planted) and Paulownia coreana Uyeki (planted), and Weigela subsessilis (Nakai) L.H. Bailey. The rare and endangered plants were designated by Korea Forest Service were 4 taxa, such as Penthorum chinense Pursh, Acorus calamus L., Lilium callosum Siebold & Zucc. and Iris ensata var. spontanea (Makino) Nakai. Floristic special plants were totally 26 taxa, which were grade V of 2 taxa, grade IV of 2 taxa and grade III of 9 taxa. Naturalized plants were 27 taxa, that was 8.3% of whole discovered vascular plants in this area. Even naturalized plants has not influence on the vegetation of Yugu stream. Since village was composed along the stream and the roads and banks were linked, naturalized plants were flowed continuously into this region. So, strategy of the conservation for this region should be designed. Based on flora, 3 types of group were discriminated such as main stream type (4 points), branch stream type (2 points) and reservior type (1 point). Each group has difference in composition of plants.

• Journal of Bio-Environment Control
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• v.14 no.3
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• pp.212-217
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• 2005

This experiment was conducted to investigate the effect of water soluble fertilizer(WSF) and slow release fertilizer(SRF) on the growth of carnation(Dianthus caryophyllus 'Invitation') cultured in C-channel mat irrigation system. Plants grown in $0.8{\~}1.0\;g{\cdot}L^{-1}$ of WSF showed the highest quality, especially on fresh and dry weight of aerial part, leaf number, total leaf area, plant height, and branch number. All plants showed increase of growth rate around 60 days after treatment, although there was a different increase rate. Total leaf area decreased its increase rate after 90 days after treatment. Carnations supplied by WSF showed better growth and quality than SRF, and the optimum concentration range of WSF for pot-carnation was $0.8{\~}1.0\;g{\cdot}L^{-1}$ in C-channel mat irrigation system.

• FLOWER RESEARCH JOURNAL
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• v.17 no.2
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• pp.88-92
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• 2009

This experiment was conducted to find out the effects of pinching on shoot growth, flowering and covering of Lonicera sempervirens growth in containers. 180 cm high pinching of plants increased shoot length compared to 60 cm low pinching and decreased lateral shoot numbers, but there was no difference in branch numbers by the pinching methods. Covering rates of the pergola were 85% with 60 cm low pinching, 74% with 120 cm middle pinching, and 62% with 180 cm high pinching. The pinched plants continued to flower from the middle of May to the middle of September. The first flowering time was in the middle of May in low pinching and in the early of June in middle and high pinching. The lower pinching height and the earlier pinching time induced earlier flowering time, and the peak flowering of pinched plants was in mid-August. To cover over 85% of the pergola screen with 3.0 m wide and 2.2 m high, two plants per 1 m needed to grow and to pinch at 60 cm height.

• The Plant Pathology Journal
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• v.38 no.6
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• pp.583-592
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• 2022

Root-knot nematode disease is a widespread and catastrophic disease of tobacco. However, little is known about the relationship between rhizosphere bacterial community and root-knot nematode disease. This study used 16S rRNA gene sequencing and PICRUSt to assess bacterial community structure and function changes in rhizosphere soil from Meloidogyne incognita-infected tobacco plants. We studied the rhizosphere bacterial community structure of M. incognita-infected and uninfected tobacco plants through a paired comparison design in two regions of tobacco planting area, Yuxi and Jiuxiang of Yunnan Province, southwest China. According to the findings, M. incognita infection can alter the bacterial population in the soil. Uninfested soil has more operational taxonomic unit numbers and richness than infested soil. Principal Coordinate Analysis revealed clear separations between bacterial communities from infested and uninfested soil, indicating that different infection conditions resulted in significantly different bacterial community structures in soils. Firmicutes was prevalent in infested soil, but Chloroflexi and Acidobacteria were prevalent in uninfested soil. Sphingomonas, Streptomyces, and Bradyrhizobium were the dominant bacteria genera, and their abundance were higher in infested soil. By PICRUSt analysis, some metabolism-related functions and signal transduction functions of the rhizosphere bacterial community in the M. incognita infection-tobacco plants had a higher relative abundance than those uninfected. As a result, rhizosphere soils from tobacco plants infected with M. incognita showed considerable bacterial community structure and function alterations.

• Journal of Sericultural and Entomological Science
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• v.29 no.1
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• pp.7-11
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• 1987

The influence of planting density, on the mulberry yield, had been studied for 5 years period since 1982. For this purpose, a hilly land (15$^{\circ}$) was selected and 5 planting density level (926, 1,667, 2,780 and 3,444 tree/10a) were used. Following results were obtained. 1. Vinyl mulching promoted 2 days earlier of green tip sprouting stage and 3 days earlier of shallow-bill stage, compared with the non-mulching. 2. It was shown that increase of the length of the branch with vinyl mulching and decrease of the mulching effect with the higher density of plants from, 2,780 tree/10a. 3. When the planting density was higher, length and width of leaf was decreased sharply, and chlorosis of the lower part of the branch was occured heavily. 4. With the higher planting density, number of branches per tree and average length of the branch was decreased. Number of shorter branch-normal branch ratio were increased. However, number of branches and total length of branch per area were shown opposite. 5. Yield of mulberry was increased for the peroid of 3 years after planting with the all the levels of planting density after that, yield increase was dully in 926 tree plot, and more dully in 1,677 trees plot, while decrease of the yield were showen with density of 2,780 and 3,444 trees plots. 6. The highest average yield for the 5 years were obtained from 2,780 trees plot, 46.6% higher than in 926 trees plot, followed 40% higher in 3,444 trees plot, and 29.9% higher in 1,667 trees plot. 7. Soil pH, organic matter, Ca and Mg decreased with cultivation, especially P2O5, pH, Ca and Mg in the density of more than 926 trees plot.

• Korean Journal of Medicinal Crop Science
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• v.4 no.4
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• pp.277-282
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• 1996

This study was carried out to understand the flowering and pollination characteristics in Bupleurum falcatum. Estimated total node numbers of primary branches were 106.6, and the total numbers of florets were theoretically 9,622 until secondary branches flower. In the sizes of floral organs according to the branch order, all of ray, pedicel, petal, pistil, stamen, ovary surface, and sepals have a tendancy to be smaller as this order: main stem> 1st branch> 2nd branch. As the branch development proceeds, the size of florets was getting smaller. Each flowering periods, especially stamen emergence, in different branch positons and in intra-branch were clearly divided. In case of florets, umbellets, and compound umbels enveloped in the gauze and paper, they showed 0% fertilization rate. However, the plants which were entirely enveloped in gauze led to the partial fertilization. Consequently, it was admitted that B. falcatum was a partly allogamous plant, fertilized in the way of entomophily. In respect of pol­linatability according to the steps of floral organs maturation, this plant was able to bear fruit after 8 days (Pistil maturation). It was at maturity stages, especially 11 through 13 days, that the maximum fer­tilization rate appeared.

• ALGAE
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• v.20 no.1
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• pp.1-13
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• 2005

The taxonomic status of three closely related species of the genus Sphacelaria, S. rigidula Kützing, S. fusca (Hudson) C.F Gray and S. didichotoma Saunders was reassessed on the basis of morphological observations from herbarium specimens and phylogenetic analysis of RUBISCO spacer sequences. Sphacelaria rigidula was characterized by having only 2-armed propagules and somewhat slender filaments. Culture experiments revealed that its propagules commonly formed secondary arms, even though they were rarely produced in the field. It is concluded that S. divaricata Montagne characterized by dichotomously branched arms in propagules shoud be synonymized with S. rigidula, based on propagule morphology and measurements. Sphacelaria fusca clearly be separated from S. rigidula by having 2-4 armed propagules. These morphological differences were highly supported by the differences in the RUBISCO spacer sequences. S. didichotoma resembles S. rigidula in having propagules with two dichotomously branched arms. However, it commonly produces the secondary arms in the field. Additionally, this species has shorter primary arms than S. rigidula. Phylogenetic analyses supported the distinction of S. didichotoma from S. rigidula. The northwestern Pacific plants, previously recorded as S. divaricata, were recognized as S. didichotoma.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.7 no.3
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• pp.40-47
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• 2011

KSNPs(Korea Standard Nuclear Power Plant) have been applied the break exclusion criteria to the high energy lines passing through containment penetration area to ensure that piping failures would not cause the loss of containment isolation function, and to reduce the resulting dynamic effects. Systems with the criteria are the Main Steam system, Feed Water system, Steam Generator Blowdown system, and Chemical & Volume Control system. In accordance with FSAR(Final Safety Analysis Report), a 100% volumetric examination by augmented in-service inspection of all pipe welds appled the break exclusion criteria is required for the break exclusion application piping. However, it is difficult to fully satisfy the requirements of inspection because 12", 8" and 6" weldolet weldments of Main Steam pipe line have complex structural shapes. To resolve the difficulty on the application of conventional UT(Ultrasonic Testing) technique, realistic mock-ups and UT calibration blocks were made. Simulations of conventional UT were performed utilizing CIVA, a commercial NDE(Nondestructive Examination) simulation software. Phased array UT experiments were performed through mock-up including artificial notch type flaws. A phased array UT technique is finally developed to improve the reliability of ultrasonic test at main steam line pipe to 12", 8" and 6" branch connection weld.

• Nuclear Engineering and Technology
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• v.53 no.3
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• pp.804-811
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• 2021

The T-junction exists widely in industrial engineering, especially in nuclear power plants, which plays an important part in nuclear power reactor thermal-hydraulics. However, the existing prediction models of the liquid entrainment are mainly based on the small branches or small breaks while there are a few researches for large branches (d/D > 0.2). Referring to the classical models about the onset of liquid entrainment of the T-junction, most of previous models regard liquid as ideal working fluid and ignore surface tension. This paper aims to study the effect of surface tension on the liquid entrainment, and develops an improved model based on the reasonable assumption. The establishment of new model employs the methods of force analysis, dimensional analysis. Besides, the dimensionless Weber number is adopted innovatively into the model to show the effect of surface tension. What is more, in order to validate the new model, three kinds of working fluids with different surface tensions are creatively adopted in the experiments: water, silicone oil and ethyl alcohol. The final results show that surface tension has a nonnegligible effect on the onset of liquid entrainment in large branch T-junction. The new model is well matched with the experimental data.