• The Journal of the Acoustical Society of Korea
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• v.21 no.3
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• pp.304-309
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• 2002

We propose the computation reduction method of real root method that is mainly used in the CELP (Code Excited Linear Prediction) vocoder. The real root method is that if polynomial equations have the real roots, we are able to find those and transform them into LSP. However, this method takes much time to compute, because the root searching is processed sequentially in frequency region. In this paper, to reduce the computation time of real root, we compare the real root method with two methods. In first method, we use the mal scale of searching frequency region that is linear below 1 kHz and logarithmic above. In second method, The searching frequency region and searching interval are ordered by each coefficient's distribution. In order to compare real root method with proposed methods, we measured the following two. First, we compared the position of transformed LSP (Line Spectrum Pairs) parameters in the proposed methods with these of real root method. Second, we measured how long computation time is reduced. The experimental results of both methods that the searching time was reduced by about 47% in average without the change of LSP parameters.

• Journal of Forest and Environmental Science
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• v.11 no.1
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• pp.22-39
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• 1995

Following "Studies on Characteristics of Pin us densiflora Forest in Kangwon Province (III)- Studies on the Tree-Root Form and Distribution on the Campus Forest, Kangwon Nat'l Univ.-", the form and distribution of root system was investigated for 5 trees in Songhyun-Ri, Wangsan-Myon, Myengju-Gun, Kangwon Province. Vertical tap roots and flat roots were established very well. In root distribution, fine roots were sparsly distributed (+), although 7 smaller quadrats($10{\times}10cm$) were found with the value of 1(+~20%) index of fine root; big roots 0.2cm thick in diameter were most common. More than 50% of fine roots and big roots were found around the depth of 10~30cm in soil.

• 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.

• Korean Journal of Medicinal Crop Science
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• v.18 no.6
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• pp.416-420
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• 2010

Root yield and quality of ginseng cultured in paddy soil was low relatively compared with that of upland soil because of moisture injury in root during rainy season. Drainage class in soils generally divided into 6 classes, and it is possible to cultivate ginseng practically in imperfectly drainage class (IDC). This study carried out to select the varieties that is suitable for paddy soil, which is easy to be generated rusty-colored root and physiological-discolored leaf. Experiment plot arranged with the condition of soil humidity contents such as poorly drainage class (PDC) and imperfectly drainage class (IDC), and upland soil. Growth characteristics and root yield were investigated in four-year-old ginseng of varieties, Cheonpoong (CP), Yeonpoong (YP), Hwangsookjong (HS), and Jakyeongjong (JK). CP among four varieties showed the highest yield in IDC and CP was the lowest ratio in leaf discoloration and rusty-colored root. HS was followed by CP in the order of root yield, but it had the weakness that the ratio of rusty-colored root was high respectively.

• Plant Disease and Agriculture
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• v.5 no.1
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• pp.58-60
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• 1999

Cultivation of a native wild vegetable, Ligularia fischeri, is hampered by Phytophthora sp. Infected plants showed wilt and eventual death due to rots on the root and basal portion. Eight isolates collected were all identified as P. drechsleri based on their mycological characteristics. The fungi showed relatively strong pathogenicity to L. Fischeri, mild to Aster scaber and Codonoposis lanceolata, and none to Circium setidens and Pimpinella brachycarpa. This is the first report of Phytophthora root rot on wild vegetables in Korea.

• Korean Journal Plant Pathology
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• v.14 no.2
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• pp.103-108
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• 1998

A Pythium species was isolated from roots of lisianthus (Eustoma grandiflorum) showing wilt symptoms and reduced growth in a greenhouse at Ichon, Kyonggi-do in 1997. The Pythium species was identified as Pythium spinosum Sawada based on various mycological characteristics. The isolate was strongly pathogenic when inoculated to root of lisianthus plants in pots. The diseased plants showed typical symptoms of root and crown rot, resulting in reduced growth of roots and shoots, and consequently wilting of the above ground part of plants.

• Korean Journal of Plant Resources
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• v.11 no.2
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• pp.176-176
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• 1998

This study was carried out to obtain the information for growth characteristics of crown gall tumor and hairy root transformed by Agrobacterium spp,. on the media with phytohormones, casein hydrolysate and activated charoal. Crown gall tumors and hairly roots were formed respectively on potato tuber discs infected by tumerfaciens A ch 5 and A.rhizogenes ATCC15834. These tumors and roots could be grown on the phytohormone free media. PCR analysis of Rol C and Vir C gene fragments confirmed that crown gall root was prompted on the medium containing 2,4-D 2mg/l with casein hydrolysate lg/l. The survival ration of crown gall tumor callus derived from potato increased on medium containing the activated charcoal 0.5∼0.2mg/l because of the prevention, on the other hand, hairly roots were necrosis on the same medium. Callus derived from hairly root were excellently grown for a short time by suspension culture on liquid medium containing 2.4-d 2mg/L and casein hydrolysate lg/l.

• Korean Journal of Plant Resources
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• v.11 no.2
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• pp.179-187
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• 1998

This study was carried out to obtain the information for growth characteristics of crown gall tumor and hairy root transformed by Agrobacterium spp,. on the media with phytohormones, casein hydrolysate and activated charoal. Crown gall tumors and hairly roots were formed respectively on potato tuber discs infected by tumerfaciens A ch 5 and A.rhizogenes ATCC15834. These tumors and roots could be grown on the phytohormone free media. PCR analysis of Rol C and Vir C gene fragments confirmed that crown gall root was prompted on the medium containing 2,4-D 2mg/l with casein hydrolysate lg/l. The survival ration of crown gall tumor callus derived from potato increased on medium containing the activated charcoal 0.5∼0.2mg/l because of the prevention, on the other hand, hairly roots were necrosis on the same medium. Callus derived from hairly root were excellently grown for a short time by suspension culture on liquid medium containing 2.4-d 2mg/L and casein hydrolysate lg/l.

• Journal of Korean Dental Science
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• v.15 no.2
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• pp.112-120
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• 2022

In this article, the contemporary root canal treatment procedure using nickel-titanium (NiTi) instruments was reviewed to understand the correlations between the properties of files and safety of the clinical usage. Literatures were reviewed according to the process of clinical procedure of the root canal preparation, mainly for shaping during orifice flaring, glide-path preparation, and main canal instrumentation. Considering the reasons for NiTi file fracture, clinically implacable issues and ideas were discussed to reduce the fracture risk and increase clinical efficiency of the NiTi file systems. Various kinds of NiTi file systems have their own characteristics and properties given from their geometries and heat treatments and so on. Proper selection and careful usage of the NiTi file systems may reduce the risk of file fracture and increase the efficiency of NiTi file systems. Understanding of the clinical implications from the mechanical properties and characteristics of the engine driven NiTi instruments may decrease the risk of NiTi file fractures and increase the success rate in root canal treatment.