• Proceedings of the KWS Conference
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• 2005.06a
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• pp.253-255
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• 2005

It has been well known that ductile fracture of steels are accelerated by triaxial stresses. The characteristics of ductile crack initiation in steels are evaluated quantitatively using two-parameters criterion based on equivalent plastic strain and stress triaxiality. The present study focuses on the effects of strength mismatching, which can elevate plastic constraint due to heterogeneous plastic straining, on critical condition to initiate ductile crack from notch root using equivalent plastic strain and stress triaxiality. In this study evaluate the criterion for ductile crack initiation in strength mismatch specimen effect of location of notch root.

• Proceedings of the IEEK Conference
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• 2002.06d
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• pp.405-408
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• 2002

LSP(Line Spectrum Pairs) Parameter is used for speech analysis in vocoders or recognizers since it has advantages of constant spectrum sensitivity. low spectrum distortion and easy linear interpolation. However the method of transforming LPC(Linear Predictive Coding) into LSP is so complex that it takes much time to compute. Among conventional methods, the real root method is considerably simpler than others, but nevertheless, it still suffers from its jndeterministic computation time because the root searching is processed sequentially in frequency region. We suggest a method of reducing the LSP transformation time using voice characteristics The proposed method is to apply search order and interval differently according to the distribution of LSP parameters. in comparison with the conventional real root method, the proposed method results in about 46.5% reduction. And, the total computation time is reduce to about 5% in the G.723.1 vocoder.

• Korean Journal of Hazardous Materials
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• v.6 no.2
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• pp.47-54
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• 2018

Mixed acid is very reactive and highly corrosive. it has been causing many accidents in a electronic industry, a steel industry, and a chemical industry. Therefore, it is required that the high safety level for the acid storage facilities. In this study, we investigated the accident causes for resent leak accidents with Root Cause Analysis (RCA). The root causes analysed by RCA were categorized as nine divisions by the their characteristics. Furthermore, each nine divisions causes was applied to the PDCA model which are using at OHSAS 18001. It is suggested that the nine division with the root causes can be the essential items for the development of the safety management manual. It is helpful to the safety improvement of the acid storage facility.

• Infection and chemotherapy
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• v.50 no.4
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• pp.340-345
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• 2018

Frequent isolation of Enterococcus faecalis from root canal treated teeth with apical periodontitis, has proposed the role of this organism in endodontic treatment failures. Different factors have been suggested in the pathogenicity of this organism. In this study, 22 E. faecalis isolates from canals of root-filled teeth were identified, and phenotypic and genotypic characteristics were investigated. No resistance to vancomycin and gentamicin was noted, and most isolates (91%) were susceptible to ampicillin. Biofilm formation was detected in 73% of the isolates and may be considered as the most important virulence factor involved in the pathogenesis of these isolates.

• Journal of Korean Dental Science
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• v.17 no.2
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• pp.75-83
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• 2024

Stevens-Johnson syndrome (SJS) is a severe adverse cutaneous drug reaction seen rarely in clinical practice. Although relatively rare, the condition can be fatal. Mainly, it is caused by side effects of certain medications. Previous reports have associated Stevens-Johnson syndrome with abnormal root development, but the other long-term dental complications have rarely been reported. In this case, the patient developed SJS at the age of 5, and abnormal root development of the maxillary and mandibular first molars and mandibular incisors was observed, as well as impaction of the mandibular canine and enamel hypomineralization of multiple teeth. Accordingly, appropriate restorative treatment and orthodontic treatment were performed, and the clinical characteristics of this symptoms and its treatment were discussed in more detail. We aim to highlight the need for dentists to be aware of the potential dental complications of SJS and to enable early diagnosis and management of the condition to avoid undesirable sequelae.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.60 no.2
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• pp.253-256
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• 2015

This study was performed to investigate the growth characteristics and inorganic components of Codonopsis lanceolata regarding regional differences. The plant height of Japanese Codonopsis lanceolata was 373.6 cm, so it's revealed that it has more vigorous growth than Korean won. The flowering time of Korean Codonopsis lanceolata was 2 weeks faster than Japanese one. Total fresh weight of root was 41.0 g and 39.0 g for Korean and Japanese respectively, thus, no significance difference was found. However, regarding fresh weight, Korean one had a more fresh weight (35.4 g) of main root parts, but Japanese one had a more fresh weight (9.6 g) of the lateral root part. Each inorganic component was found more in the aboveground parts, regardless of the region and the content of K was the largest. Regarding the content of macroelements for each part of Codonopsis lanceolata, the content of Na, Mg, P, S, and Ca in Korean Codonopsis lanceolata was found the highest on the leaf, followed by stem and root. In the case of Japanese Codonopsis lanceolata, same result was found on the content of Mg and Ca, however, the highest content of Na and P was found in the stem.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.4
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• pp.251-258
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• 2017

This study was conducted to identify transition characteristics of arsenic (As), cadmium (Cd), and lead (Pb) and to calculate bio-concentration factors (BCF) in the three perennial root medicinal plants, namely Codonopsis lanceolata (Deoduck), Platycodon grandiflorum (Balloon flower) and Panax ginseng (Korean ginseng) grown in major medicinal plant producing districts in Korea. Average BCF values ranged from 0.009~0.029 in As, 0.334~1.453 in Cd, and 0.021~0.023 in Pb in three perennial root medicinal plants. The BCF values increased in the order of ginseng (0.029) > deodeok (0.012) > balloon flower (0.009) for As, balloon flower (1.453) > deodeok (0.685) > ginseng (0.334) for Cd, and ginseng (0.023) > deodeok (0.022) > balloon flower (0.021) for Pb. The BCF values calculated in this study will be useful for predicting the uptake of heavy metal (loid)s. Further study on uptake and accumulation mechanism of toxic metal (loid)s by agricultural products is required to assess the human health risk associated with soil contamination.

• Journal of the Korean Institute of Landscape Architecture
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• v.34 no.3 s.116
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• pp.79-90
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• 2006

Tamarix chinenis blooms twice a you and its flowers, branches and leaves make the adjustment of tree shape. Propagation methods and growth characteristics of T. chinensis were studied in order to ascertain its potential use as one of vegetation resources for coast forestation and landscaping. The study results indicated that 1 or 2 you old hard wood cuttings showed higher rooting ratio than greenwood or semi hard wood cuttings. One to one mixture between vermiculite and pearlite appeared to be the best for bed soil, and sea sand and silt(loess) mixture was the next. Sea sand and granitic soil followed after. In terms of seasonal differences, spring cuttings showed the best rooting ratio, root number, and root length. Fall cuttings followed after spring cutting, and summer cuttings showed worst results regarding rooting ratio, root number, and root length. The best rooting promotion effects of growth regulators were observed with sea sand bed soils. There was no significant difference among growth regulators in terms of rooting and shoot growth. Low concentration below 100 ppm of growth regulators was enough for rooting promotion effect. In general, the number and mean length of roots and shoots were showed the excellent records in the sites with high rooting ratio. The study result strongly showed that T. chinensis can be considered as a suitable tree for coast forestation and landscaping because of its easy cutting propagation and rapid growth on saline lands.

• Korean Journal of Plant Tissue Culture
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• v.26 no.3
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• pp.205-209
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• 1999

Chinese foxglove(Rehmannia glutinosa) is receiving much attention as one of the principal medicinal crops and the crud drug. This study was conducted to obtain the basic breeding information of Chinese foxglove derived from tissue culture. To compare plant characteristics between local variety and tissue cultured seedlings, plant growth and root yield has been investigated. In addition, catalpol and free sugar contents were also analized. The ability for the storage of root stock originated from tissue culture seedlings were better than that of local variety. The growth and root yield of in vitro propagated plants were superior to those of conventionally propagated plants. Root yield of 1-year-old and 2-year-old seedlings investigated 112% and 246% respectively than Seacheon local shows 384 kg/10 a. Although there were no significant different between tissue culture seedlings and conventionally propagated one, slight decline of component contents in tissue culture plants were still existed. Investigated sugar content among Seocheon local, 1-year-old tissue culture seedlings, and 2-year-old tissue culture seedlings were 1.86%, 1.21%, and 1.10% respectively. Catalpol content as one of standard materials indicates 0.46% in Seocheon local and 0.40% in tissue cultured ones.

• The Korean Journal of Physiology
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• v.24 no.2
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• pp.389-402
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• 1990

The physiological characteristics of the neurons receiving the ventral root afferent inputs were investigated in the cat. A total of 70 cells were identified in the lumbosacral spinal cord. All these cells responded only to the C-strength stimulation of the distal stump of cut ventral root and the estimated conduction velocities of the VRA fibers were not faster than 4 m/sec. The majority of them were silent in resting state. For 49 cells, their peripheral receptive fields were characterized. Among them, 25 cells were exclusively excited by VRA inputs, 8 were inhibited and the remaining cells recevied both excitatory and inhibitory VRA inputs. According to the response pattern to the mechanical stimuli applied to their receptive fields, only a fourth of them were typical high threshold cell, a sixth, wide dynamic range cells, while remainings were a rather complex cells. Most of the cells receiving VRA inputs, received only the A ${\delta}-peripheral$ nerve inputs. Intravenous injection of morphine decreased the response of spinal cells to the VRA activation. The responses were abolished completely by counter irritation to the common peroneal nerve with C-strength-low frequency stimuli. These physiological properties of the spinal neurons receiving the VRA inputs are differ in some aspect from the spinal neurons receiving nociceptive inputs from the periphery, but still were consistent with the contention that VRA system might carry nociceptive informations arising from the spinal cord and/or neraby surrounding tissues.