• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2001.10b
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• pp.10-10
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• 2001

• Structural Engineering and Mechanics
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• v.27 no.4
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• pp.425-438
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• 2007

Large changes in stiffness associated with cracking and yielding of reinforced concrete sections may be expected to occur during the dynamic response of reinforced concrete frames to earthquake ground shaking. These changes in stiffness in stories that experience cracking might be expected to cause relatively large peak interstory drift ratios. If so, accounting for such changes would add complexity to seismic design procedures. This study evaluates changes in an index parameter to establish whether this effect is significant. The index, known as the coefficient of distortion (COD), is defined as the ratio of peak interstory drift ratio and peak roof drift ratio. The sensitivity of the COD is evaluated statistically for five- and nine-story reinforced concrete frames having either uniform story heights or a tall first story. A suite of ten ground motion records was used; this suite was scaled to five intensity levels to cause varied degrees of damage to the concrete frame elements. Ground motion intensity was found to cause relatively small changes in mean CODs; the changes were most pronounced for changes in suite scale factor from 0.5 to 1 and from 1 to 4. While these changes were statistically significant in several cases, the magnitude of the change was sufficiently small that values of COD may be suggested for use in preliminary design that are independent of shaking intensity. Consequently, design limits on interstory drift ratio may be implemented by limiting the peak roof drift in preliminary design.

• Journal of Communications and Networks
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• v.13 no.6
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• pp.655-663
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• 2011

Diffuse optical wireless (DOW) systems have the advantage that they do not require point-to-point siting so one transmitter can communicate with several receivers. In this paper, we investigate multiple access scheduling methods for downlink orthogonal frequency division multiplexing (OFDM) in diffuse optical wireless networks. Unlike the radio frequency (RF) channel, the DOW channel has low-pass filter characteristics and so requires different scheduling methods than those developed for the RF channel. Multi-user diversity orthogonal frequency division multiple access (OFDMA) systems nominate a cluster of subcarriers with the largest signal-to-noise-ratio for transmission. However, in a DOW channel, most users would choose the lowest frequency clusters of subcarriers. To remedy this problem, we make two proposals. The first is to use a variable cluster size across the subcarriers; the lower frequency clusters will have fewer subcarriers while the higher frequency clusters will have more subcarriers. This will equalize the capacity of the clusters. The second proposal is to randomize a user's cluster selection from a group of clusters satisfying a minimum threshold. Through simulation it is shown that combining these strategies can increase the throughput while ensuring a fair distribution of the available spectrum.

• The Journal of the Korean dental association
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• v.10 no.4
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• pp.209-212
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• 1972

The effect of pyridoxine on the incisors were histochemically studied for the purpose of identifying the phosphoric acid. The microscopic observations were carried out by means of phosphoric acid reaction(Serraet Queiroz-Lopes method), mucoprotein reaction (Clara method), periodic acid-Schiff reaction (McManus method), methylen blue stain and hematoxylin-eosin stain. In the experimental result, it was found that phosphoric acid reactions of ameloblast, Tomes' process and preenamel were remarkably increased after pyridoxine administration.

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.10a
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• pp.10-10
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• 2001

Selenium is an essential nutritional element for several animal species and human. It has been also seen, that low levels of selenium in the diet can cause many diseases. This metalloid was defined like a "double face" element because it possesses antioxidant, antimutagen, anticarcinogen but also mutagenic and carcinogenic effects. The most important metabolic role of selenium in the animal species is its presence in the Glutathione Peroxidase(GSH-Px). (omitted)

• International Journal of Concrete Structures and Materials
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• v.11 no.2
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• pp.275-284
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• 2017

A formula to estimate the yield displacement observed in the pushover analysis of coupled wall lateral force-resisting systems is presented. The estimate is based on the results of an analytical study of coupled walls ranging from 8 to 20 stories in height, with varied amounts of reinforcement in the reinforced concrete coupling beams and walls, subjected to first-mode pushover analysis. An example illustrates the application of these estimates to the performance-based seismic design of coupled walls.

• Journal of Radiation Industry
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• v.4 no.3
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• pp.253-257
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• 2010

This experiment was carried out to investigate the effects of gamma-radiation on the rooting, growth, and color mutation in poinsettia. Using 10 poinsettia varieties ('Lollipop', 'Little Peace', 'Happy Day', 'Early Bird', 'Pixy Red', 'Happy Time', 'Heidi', 'Red Bell', 'Clara', and 'Scarlet') bred by National Institute of Horticultural and Herbal Science, 100 Gy of gamma ray was irradiated at the stage of callused cuttings. Four weeks after sticking cuttings in the rooting media, 8 cultivars showed 100% of root formation, but 'Early Bird' rooted 24.4% and even died off during the cutting propagation. After planting rooted cuttings, survival rate until flowering time varied among irradiated cultivars. While 'Pixy Red' and 'Heidi' survived about 98%, 'Clara', 'Happy Day', and 'Early Bird' survived lesser than 30%. All irradiated plants showed remarkably shorter plant height, lesser branch numbers than non-irradiated control plants. Thirty color mutants were obtained among 281 plants survived until flowering time. Nine mutants were complete color mutated branches, whereas 21 mutants were partially color mutated bracts and transitional leaves. Color patterns mutated by 100 Gy of gamma ray were divided into pink, hot pink, light red and spotted (pink spots with red main color). Pink mutants were commonly obtained. Complete color mutants were discovered from 4 plants of 'Pixy Red', 2 plants of 'Red Bell' and 3 plants of Lollipop.

• Tuberculosis and Respiratory Diseases
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• v.53 no.2
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• pp.127-135
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• 2002

Background : Idiopathic interstitial pneumonia is characterized by chronic inflammation and pulmonary fibrosis. The clara cell 10 kD protein (CC10, also designated CC16) is synthesized by the bronchial epithelium and has been suggested to have a potent anti-inflammatory effect. Therefore, CC-10 might be a candidate for controlling the inflammatory events in patients with idiopathic interstitial pneumonia. The aim of this study was to determine if the degrees of pulmonary fibrosis in idiopathic interstitial pneumonia is associated with CC-10 in the BAL fluid. Materials and Methods : The BAL fluid was collected from 29 patients and 10 controls. Densitometric analysis of the western blot assay for the CC-10 was subsequently performed. The RI (relative intensity) of each band was compared according to the diagnosis, the radiological degrees of pulmonary fibrosis and the relative proportion of inflammatory cells in the BAL fluid. Results : There were no differences in the CC-10 expression levels in the BAL fluid between the patients (RI $77.5{\pm}75.8%$) and the controls ($70.7{\pm}39.8%$) (p>0.05). In addition, the degrees of pulmonary fibrosis and airway inflammation in patients with usual interstitial pneumonia were not associated with CC-10 expression in the BAL fluid (p>0.05). Conclusion : This study suggests that CC-10 expression is not associated with the degrees of pulmonary fibrosis in patients with usual interstitial pneumonia.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.11a
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• pp.193-194
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• 2009

This report makes an important correction to estimating angular dependent emission pattern of Organic Light-Emitting Diodes (OLEDs). Today, experiments on measuring angular light intensity of OLEDs are conducted without considering the difference between the view angle identified by photodiode and the actual angle being measured. ITO-TPD-$Alq_3$-LiF-Al Organic Light-Emitting Diode was used to find out the degree of the error. In this case, the difference in average was about $1^*$, which is highly significant. Since the difference varies from case to case, the need for adjustment must be evaluated for each case.

• Structural Engineering and Mechanics
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• v.23 no.4
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• pp.369-386
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• 2006

The influence of reinforcement buckling on the flexural response of reinforced concrete members is studied. The stress-strain response of compression reinforcement is determined computationally using a large-strain finite element model for bars of varied diameter, length, and initial eccentricity, and a mathematical expression is fitted to the simulation results. This relationship is used to represent the response of bars in compression in a moment-curvature analysis of a reinforced concrete cross section. The compression bar may carry more or less force than a tension bar at a corresponding strain, depending on the relative influence of Poisson effects and bar slenderness. Several cross-section analyses indicate that, for the distances between stirrups prescribed in modern concrete codes, the influence of inelastic buckling of the longitudinal reinforcement on the monotonic moment capacity is very small and can be neglected in many circumstances.