• Journal of Bio-Environment Control
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• v.25 no.2
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• pp.100-105
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• 2016

In this study we investigated the suitability of horticultural main organic root substrate materials (peatmoss, coir) for the development proper root substrate for working with bulb onion transplanter. We investigated seedling sprout ratio, growth and characteristics (bulk density, root substrate cohesion) those are suitable for mechanical transplanting by mixing with inorganic materials(red clay etc.). Although both seedling growth and root substrate bulk density were similar in peatmoss and coir based root substrates, we found that peatmoss mixing had higher root substrate cohesion compared to coir mixing. We assume that higher cohesion properties of peatmoss based root substrate will give more weight of root part during mechanical transplanting of young onion seedlings in the field. Because of this, we suggest that peatmoss is the appropriate ingredient for developing root substrates for working with bulb onion transplanter.

• Geotechnical Engineering
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• v.7 no.2
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• pp.51-66
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• 1991

In the stability analysis of hillside slopes, the roots of vegetation have been considered to act as a soil reinforcement. In order to predict the amount of increase in soil shear resistance, produced by tensile strength of roots that intersect a potential slip surface in hillside slopes, new soil -root interaction models are proposed in this paper. For this purpose, firstly, laboratary teats and in-situ tests wert performed on soil-root systems, and experimental results were compared with a couple of soil-root interaction models which had been proposed by Gray, Waldron, and Wu etc. Based on this comparison, a new soil-root interaction model is proposed. Secondly, a probabilistic soil-root model is proposed based on statistical analysis considering random nature of root distribution, root characteristics, and soil-root interactions. Finally, to examine the effect of this root reinforcement system on stability of hillside slopes, a simple three-dimensional stability analysis was performed, and it was shown that root reinforcement had a significant stabilizing influence on shallow slips rather than deep slips in hillside slopes.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.55-58
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• 2000

SiGe heterojuction bipolar transistors (HBT) have been studied and applied for advanced high speed integrated circuits. Device characteristics of SiGe HBT depending on the Ge profile of the transistor base region have been analysed using a device simulator, ATLAS/BLAZE. The models and parameters have been calibrated to the measured characteristics of the device, having a trapeziodal base profile, including the cut-off frequency of 45GHz and the dc current gain of 200. The Ge concentration which increases linearly, exponentially, or root-functionally from the emitter-base junction to the base-collector junction, has been tried to find out the influence on the device characteristics. The cut-off frequency and gain rather strongly depends on the exponential and root-functional Ge base profiles, respectively.

• Korean Journal of Plant Resources
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• v.16 no.1
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• pp.8-14
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• 2003

This study was aimed to obtain basic information on the characteristics of local cultivars of burdock(Arctium lappa L.) grown in Yeong-Nam region. The characteristics of seeds were shown a remarkable diversity among the local cultivars. Germination rate was the highest at 25$^{\circ}C$ and Munkyong' as the highest germination rate(42.2%) at l0$^{\circ}C$ respectively. In Youchon' and 'Chilgok', about 10％ was bolted but the other was rarely or none. The range of root length was 62∼77cm and lateral root number was maximum 5.5('Koryong') and minimum 0.3('Songju). 'Chongdo I' contents 14.2mg/100g of tannin in root and 'Kyongsan', 'Koryong', 'kyongiu',’ Kumi' and 'Haman' taste not bitter in leaves.

• Explosives and Blasting
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• v.21 no.1
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• pp.69-76
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• 2003

Test blasting has been performed with V-cut to investigate the characteristics. Blasting vibrations were measured at two directions, the proceed direction and side direction. Propagation characteristics were determined by regression analysis; square root scaled distance and cube root scaled distance with maximum charge per delay of the blast. Testing result, The cross point was 62m in the allowable vibration velocity of 3mm/sec and 46m In 5mm/sec. Also, vibration level with measuring point was highest and decayed fastest, adapting to cube root scaled distance, for the proceed direction on ground.

• Korean Journal of Plant Resources
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• v.34 no.5
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• pp.403-410
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• 2021

The aim of this study was to investigate the growth characteristic and ginsenoside contents of 7 and 13 year-old wild-simulated ginseng (Panax ginseng C.A. Meyer) according to rusty root. The root growth characteristics of wild-simulated ginseng were did not shows significant difference according to the rusty root. The results of ginsenoside contents of wild-simulated ginseng according to rusty root, ginsenoside Rb1 and Rg1 of 7 year-old wild-simulated ginseng were had shows a significantly higher in rusty root compare to general root. On the other hand, ginsenodie Rc, Rd, Re and Rg2 were significantly higher in gerneral root. In the case of 13 year-old wild-simulated ginseng, the contents of ginsenoside did not shows to significant difference according to rusty root. The results of correlation analysis between growth characteristics and ginsenoside content of general root, the ginsenoside Rb2, Rc, Rd, Rf, Rg1 were positive correlation with root length, while as the ginsenoside Rd of rusty root was shows significantly negative correlation with root length. The results of this study was might be able to improve awareness of consumer related to rusty root of wild-simulated ginseng. Moreover, might be help to provide useful information on the establish quality standard and distribution system of wild-simulated ginseng.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.6
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• pp.738-744
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• 2011

The reliability of blade root fixing section is required to endure the centrifugal force and vibration stress for the last stage blade of steam turbine in thermal power plant. Most of the domestic steam turbine last stage blades have finger type roots. The finger type blade is very complex, so the inspection had been performed only on the exposed fixing pin cross-section area due to the difficulty of inspection. But the centrifugal force and vibration stress are also applied at the blade root finger and the crack generates, so the inspection method for finger section is necessary. For the inspection of root finger, inspection points were decided by simulating ultra-sonic path with 3D modeling, curve-shape probe and fixing jig were invented, and the characteristics analysis method of ultrasonic reflection signal and defect signal disposition method were invented. This invented method was actually executed at site and prevented the blade liberation failure by detecting the cracks at the fingers. Also, the same type blades of the other turbines were inspected periodically and the reliability of the turbine increased.

• The Korean Journal of Mycology
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• v.29 no.2
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• pp.127-130
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• 2001

A Pythium species was isolated from roots of Codonopsis pilosula showing wilt symptoms in a field at Yonchon, Kyonggido of Korea from late June to early August in 2000. The Pythium species was identified as Pythium myriotylum Drechsler based on various mycological characteristics. The isolate was strongly pathogenic when inoculated to root of C. pilosula plants in pot. The inoculated plants showed typical symptoms of root rot, resulting in reduced growth of root and consequently wilting of above ground part of plants. Pythium root rot of C. pilosula caused by P. myriotylum has not been reported previously in Korea.

• Journal of the korean academy of Pediatric Dentistry
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• v.47 no.1
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• pp.25-35
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• 2020

The purpose of this study is to evaluate the morphological characteristics of the roots and roots canals of primary molar teeth using Cone-Beam Computed Tomography (CBCT). A total of 68 CBCT images of children aged 4 - 5 years was used for this study. A total of 160 molar teeth were analyzed. Various parameters such as the number of roots and canals, length of root and root canal, and the angulation and shape of the roots were analyzed. All maxillary primary molars had 3 roots. The presence of 2 root canals in 1 root was only observed in the mesiobuccal root of maxillary primary second molars. Most mandibular primary molars had 2 roots, and most mesial roots had 2 root canals. Concerning the length of the roots, the palatal root of the maxillary primary molar was found to be longest whereas the distobuccal root was shortest. In mandibular primary molars, the mesial root was longer than the distal root. In maxillary primary molars, the palatal root had the greatest angulation whereas the distal root has the greatest in mandibular molars. The root and root canals of maxillary primary molars were more curved in shape whereas mandibular primary molars were straight.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.8
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• pp.1124-1129
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• 2009

Quality characteristics of lotus root pickle added with beet water extract were investigated. Lotus root slices were salted with NaCl, soaked into pickling solution, and then stored at $20^{\circ}C$. Throughout the whole storage periods, pH, acidity, saltiness of pickles (control, 10% beet extract, 20% beet extract, 30% beet extract, 40% beet extract) ranged 3.45$\sim$3.51, 1.42$\sim$1.88% and 1.86$\sim$1.91, respectively. The pH of the experimental groups slowly decreased during the fermentation. The total acidity of the experimental groups were increased. In terms of color values, L and a values were decreased, but b values were increased, with increasing beet extract content. The hardness of lotus root pickles measured instrumentally was higher in lotus root pickle added with 40% beet water extract than in control pickle. Overall, based on sensory evaluation, lotus root pickle added 30% beet extract was preferred over the other samples.