• Journal of Korean Society of Forest Science
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• v.90 no.4
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• pp.458-464
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• 2001

In this study, the annual growth of roots and their branching forms of Norway spruce(Picea abies [L.] Karst.) were analysed to compare the development of their root in the differently acidified forest soils. And there was no significant difference among the stands for the modified roots and the non-modified roots depending on the root branch forms, and however in the most acidified Weidenbrunnen stand, the modified roots, the abnormal root branch form such as fork, gun and rake types were appeared. As a result of the ring of the root, the annual horizontal root growth were 6.3cm for Weidenbrunnen and Barbis stands and 9.5cm for Eberg$\ddot{o}$tzen stand. The average annual vertical root growth was 4.4cm, 5.4cm, and 6.7cm for Weidenbrunnen stand, Barbis stand, and Eberg$\ddot{o}$tzen stand, respectively. The cross section area by root distribution at 80cm deep showed that the thick and thin roots were evenly distributed in of Eberg$\ddot{o}$tzen stand and the sum of root cross section area was $32.6cm^2$. In Barbis stand, the thick roots were distributed in the center while the thin roots were comparatively rare. And the sum of root cross section area was $29.2cm^2$. In Weidenbrunnen stand, only a few thin roots were found, and the total root cross section area was $10.9cm^2$. The stability coefficient of roots were in the order of Eberg$\ddot{o}$tzen stand(1.04), Barbis stand (0.3), and Weidenbrunnen(0.08) stand. Among the investigated Norway spruce stands, the modified abnormal root branching form and the low root growth appeared in the Weidenbrunnen stand could be attributed by the soil acidification etc.

• Journal of Ginseng Research
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• v.22 no.4
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• pp.299-303
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• 1998

To know possibility of raw ginseng production for white- and red-ginseng by direct-sowing culture, seeds were directly sowed or seedlings were transplanted at soil condition of sandy loam in ginseng field. After cultivation, the characters of 5-year-old ginseng were investigated. Number of survived plants was increased with increase the seeding quantity in direct-sowing culture, the survived plants in direct-sowing culture was higher than that of transplanting one. Rate of the numbers of survived plants to numbers of seeds sowed in plots of 134 or 90 seeds sowed per tan, 180 x 90cm area, inspire of high number of survived plant was high compared to that of transplanting culture. Occurrence rate of rusty root of ginseng in direct-sowing culture was low significantly compared to that of transplanting culture. Root yield showed in the order of 134, 268, 90 seeds sowed, the values of yield in direct-sowing culture were high obviously compared to that of transplanting one. Individual root weight was increased with decrease the seeding quantity, however, the root weight in plot of 90 seeds sowed showed almost equal the weight in transplanting culture. The number of usable raw ginseng for white- and red-ginseng was increased with decrease of the seeding quantity; the numbers were higher than that of transplanting culture remarkably. We concluded that optimum seedling rate in direct-sowing culture of ginseng was 90 to 134 seeds per tan considering the yield per area and production rate of large root.

• Journal of Aerospace System Engineering
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• v.6 no.1
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• pp.1-6
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• 2012

During helicopter rotor system development process, whirl tower test is conducted basically. For conducting whirl tower test during bearingless hub development process, design new blade or using existing blade with repair or remodeling. Because simple shape and efficient aerodynamic characteristic, BO-105 blade is used for hub system development widely. Originally BO-105 Blade is used for hingeless hub, so flap stiffness and lag stiffness on blade root area is relatively low. So appling BO-105 blade to bearingless hub whirl tower test, root area have to be reinforce. In this paper, suggest reinforcement method of BO-105 blade root area.

• Transactions of the Korean Society of Automotive Engineers
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• v.3 no.5
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• pp.1-9
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• 1995

The purpose of this study is to develop a computer simulation program for analyzing load transmission characteristics of a helical gear system in design stage. In this analysis, the rotational delay, load distribution, root stress, and contact area are investigated. That is, the influence function of deflection is obtained by finite element analysis and the influence function of approach and gear tooth error are considered. Load distribution, rotational delay, and contact area are calculated by solving load-deflection equation which includes these influence functions and tooth error, and the influence function of the bending moment is obtained by finite element analysis. The root stress is calculated by the load distribution and the influence function of the bending moment. The results of the simulation are cross-checked through a specially designed experimental set-up.

• Journal of Ginseng Research
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• v.8 no.1
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• pp.57-64
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• 1984

In order to clarify an effect of seedling weight on the growth pattern of ginseng, seedlings ranged from 0.4g plant to 1.8g plant were transplanted, and then the characters of 5- and 6-year-old ginseng were investigated. The characters of root and leaf, such as length and diameter of main root, root weight, leaf area, and leaf dry weight of 5- and 6-year-old ginseng originated from large seedlings were superior as compared with those from small seedlings, and percentage of missing plant was increased with the increase of seedling weight. There were, however, no significant difference in stem length, stem dry weight, number of seeds per plant and number of palmate leaves and leaflets per plant in 5- and 6-year-old ginseng and these characters were not affected by the weight of seedings transplanted. Root field per unit area was higher in seedings of above 0.6g/plant than in small seedlings.

• Journal of Periodontal and Implant Science
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• v.51 no.4
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• pp.276-284
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• 2021

Purpose: The aim of this randomized clinical trial was to assess whether chemical cleansing using a sulfonic/sulfuric acid gel solution (HBX) as an adjunct to scaling and root planing (SRP) resulted in a decrease in residual plaque and calculus in deep periodontal pockets compared to SRP alone. Methods: Fifty-six patients with 56 hopeless posterior teeth, scheduled for extraction due to severe periodontitis, were enrolled in this study. Each tooth was randomly assigned to 1 of the 2 experimental procedures. The test teeth were subjected to the irrigation of the subgingival area with HBX for 2 minutes, followed by SRP with hand and ultrasonic instruments for 14 minutes, and then extracted. The control teeth received only mechanical instrumentation before extraction. Residual biofilm was evaluated on photographs and measured as total area and percentage of root surface covered by remaining plaque (RP) or calculus (RC) after treatment. Results: The initial pocket depth (PD) and total subgingival root surface area were similar between the 2 treatment groups. After treatment, the total subgingival root area covered by RP and RC was statistically significantly larger (P<0.001) in the control group than in the test group. The test teeth showed a lower percentage of RP, but a higher percentage of RC than the control teeth (both P<0.001). Complete calculus removal was achieved in 42% of the control teeth surfaces and in 25% of the test teeth surfaces for a PD of 4 mm. Conclusions: The additional chemical cleansing with HBX resulted in a statistically significant improvement in bacterial plaque removal during SRP of deep pockets, but it was not effective in reducing calculus deposits.

• Journal of the Korean Society of Tobacco Science
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• v.19 no.1
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• pp.18-23
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• 1997

The study was carried out to clarify reasonable production of healthy seedling, optimal Pot depth, and appropriate transplanting time, which can be deduced from understanding of seedling quality. Seedling quality results from growth of root and shoot, morphology and distribution of root system under influence of Pot depth during seedling growing period. Stem height, shoot dry weight, leaf area and leaf number were increased in proportion to depth of pots. Growth of shoot and root during seedling growing period showed the most dramatic development between 20th and 25th day after temporary planting. Root number increased as pot depth decrease and total root length and dry weight increased as pot depth increase. In 5cm pot, relative multiplication rate was higher and mean extension rate was lower than other depth of Pot. The limitation of pot volume in which rhizosphere was located enhance the development of roots of second and third order. At 20th days after temporary Planting root distribution was relatively uniform in length and development of adventitious root on stem base was poor as Pot depth decreased.

• Journal of Ginseng Research
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• v.12 no.1
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• pp.40-46
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• 1988

This study was conducted to investigate the optimum temperature and light intensity of photosynthesis and transmittance in the shade for better growth and root yield of ginseng. The 3-year-old ginseng plants grown under the shade of 5, 10 and 20% transmittance did not show any significant difference in the stem length, stem diameter, leaf area and root length. The root diameter markedly increased under the shade of 10% and 20% transmittance, and the root was the heaviest under the shade of 20% transmittance. The 6-year-old ginseng plants grown at 20% transmittance showed the largest root diameter but the root length was not influenced by transmittance. The root was heaviest in the shade of 20% transmittance.

• Korean Journal of Medicinal Crop Science
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• v.22 no.5
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• pp.384-390
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• 2014

This study was carried out in order to investigate the early growth and root development characteristics of Peucedanum japonicum container seedlings. The experiment was performed by containers (128 and 200 cavities containers) and shading levels (0%, 35%, 50% and 75% shading). Germination rate of P. japonicum seeds was getting higher in the lower shading level and the highest in the full sunlight (71.9%). Plant height was the highest under 50% shading of all containers. Fresh weight and dry weight of the shoot (leaves + stem) were the highest under 50% shading of all containers, too. Meanwhile, fresh weight and dry weight of the root per plant were the highest under the full sunlight of 128 cavities container such as 0.34 g and 0.03 g, respectively. Total root length, root project area and root surface area were higher under the full sunlight of 128 cavities container such as 234.5 cm, $6.6cm^2$ and $20.8cm^2$, respectively and the next higher was under 35% shading such as 201.7 cm, $5.9cm^2$ and $18.4cm^2$, respectively. A case of root volume was the highest with $0.15cm^3$ under the full sunlight. As a result of the surveying the whole experiment, it is concluded that the shoot and root of P. japonicum seedling grow nicely by maintaining 35% shading.

• Korean Journal of Medicinal Crop Science
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• v.22 no.2
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• pp.154-159
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• 2014

This study was carried out in order to investigate the early growth and root development characteristics of Atractylodes japonica container seedling. Experiment was performed by light intensity (100%, 60%, 25% and 10% of full sunlight). Height was surveyed well under 25% of full sunlight (overall 11.013.0%). Root collar diameter was the highest in the full sunlight (7.52 mm). It was the highest fresh weight (1.52 g, 0.92 g, 0.90 g and 3.34 g) under 25% of full sunlight, root dry weight was getting higher in the higher light level and the highest in the full sunlight (0.13 g). Total root length, root project area, root surface area and root volume were the highest under 25% of full sunlight (434.7 cm, $17.4cm^2$, $54.7cm^2$, $0.55cm^3$, respectively) and the lowest under 10% of full sunlight. As a result of surveying the whole experiment, A. japonica is judged nicely by maintaining 25% of full sunlight, excepting 10% of full sunlight. And light levels during the early growth are overly important to improve early growth.