• Journal of the Mineralogical Society of Korea
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• v.22 no.4
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• pp.343-352
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• 2009

High-resolution Solid-state NMR provides element specific and quantitative information and also resolves, otherwise overlapping atomic configurations in multi-component non-crystalline silicates. Here we report the preliminary results on the effect of composition on the structure of CMAS (CaO-MgO-$Al_2O_3-SiO_2$) silicate glasses, as a model system for basaltic magmas, using the high-resolution 1D and 2D solid-state NMR. The $^{27}Al$ MAS NMR spectra for the CMAS silicate glasses show that four-coordinated Al is predominant, demonstrating that $Al^{3+}$ is network forming cation. The peak position moves toward lower frequency about 4.7 ppm with increasing $X_{MgO}$ due to an increase in $Q^4$(4Si) fraction with increasing Si content, indicating that Al are surrounded only by bridging oxygen. $^{17}O$ MAS NMR spectra for $CaAl_2SiO_6$ and $CaMgSi_2O_6$ glasses qualitatively suggest that NBO fraction in the former is smaller than that in $CaMgSi_2O_6$ glasses. As $^{17}O$ 3QMAS NMR spectrum of model quaternary aluminosilicate glass resolved distinct bridging and non-bridging oxygen environments, atomic structure for natural magmas can also be potentially probed using high-resolution 3QMAS NMR.

• Geotechnical Engineering
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• v.11 no.4
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• pp.37-48
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• 1995

The dynamic behavior of dry sand under different vibration conditions is studied through laboratory experiments. Sinusoidal and random vibration experiments of sand are carried out in vertical direction under various surcharge loads. Five different sand samples are selected for the azperiment. They are composed of four different -size samples of particles and one sample which is simulated the field condition. In case of sinusoidal vibration, the change in relative density is measured with acceleration levels. To produce an acceleration, the vibration amplitude is maintained within the range of 0.4mm~0.6mm and the vibration frequency is changed within the range of 3Hz~40Hz. In case of random vibration, the combined sinusoidal acceleration is produced by a random vibration generator and the change in relative density is measured by an accelerometer. Based on the experimental results, it is found that the sandy soil is compacted to 94%~99% of relative density by vertical acceleration and the peak acceleration producing the maximum relative density is proportional to the difference between maximum and minimum void ratios. It is also found that the effect of surcharge loading : the greater the surcharge loading, the larger the change in relative density and the greater the acceleration required to change the relative density.

• Journal of Korean Home Economics Education Association
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• v.21 no.1
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• pp.71-88
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• 2009

This study was a quasi-experimental study to test a research question: Is the school library-assisted instruction effective in enhancing students' academic achievement? To solve the research question, 14 hours of school library-assisted instruction and traditional lecture were carried out to 164 9th grade middle school female students(82 of experimental group, 82 of control group). SPSS 12.0 was used for statistical analysis of frequency analysis, $x^2$-test, and t-test. The results showed that there was a statistically significant difference between the pre-test and the post-test in the total academic achievement scores of both experiment group and comparison group. There was a statistically significant difference between the pre-test and the post-test in paper and pencil test scores for comparison group. There were statistically significant differences between the pre-test and the post-test both in paper and pencil test scores and performance assessment for two groups. But there were no statistically significant differences between the experiment group and the comparison group in post-test pre-test gap of total academic achievement, paper and pencil test, and performance assessment scores.

• Korean Journal of Clinical Pharmacy
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• v.23 no.1
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• pp.33-41
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• 2013

Background: Prevalence of depression comorbid with neurologic disorders such as Alzheimer' disease (AD), Parkinson's disease (PD) and vascular dementia (VD) is higher than that of primary depression. Antidepressant medications, suggested by many researches for depression comorbid with neurologic disorders such as AD, PD and VD, are mainly selective serotonin reuptake inhibitors (SSRI). Objective: The primary objective of this study is the evaluation of antidepressant drug therapy for AD, PD and VD. Method: This study was a retrospective study based on medical records, carried out for 3 years and 6 months (Jan. 2007~Jul. 2010). Patients, diagnosed as comorbid depression through Beck Depression Inventory (BDI), Cornell Depression Scale (CDS), Geriatric Depression Scale (GDS) among neurologic out-patients of Chungnam National University Hospital because of AD, PD and VD, were selected. The results were evaluated by efficacy and safety of antidepressant drug therapy. Results: In result, the prescribing rates of antidepressants were 30%, 55% and 40% for each AD, PD and VD. Depression cure rates of patients receiving antidepressants vs patients not receiving antidepressants were 40% vs 39%, 33% vs 23% and 38% vs 30% for AD, PD and VD. The frequencies of prescriptoin of SSRI were 21%, 11% and 27% for each AD, PD and VD. The frequencies of prescriptoin of benzodiazepine (BZD) was 61%, 82% and 61% for each AD, PD and VD. The ratio of single BZD prescription was more than that of combination prescription of antidepressants. Tricyclic antidepressants (TCA) were rarely prescribed. The rate of patients with BZD-related side effects was 54%. The most frequent side effects of BZD were dizziness (30%), drowsiness (21%) and headache (16%). Side effects of SSRI were rare. Conclusion: In conclusion, the frequencies of prescription of antidepressants were not common for AD, PD and VD. There was little difference in depression cure rate between patient receiving antidepressants and not receiving. Even though SSRI has to be the highest priority of usage, the frequencies of prescription of SSRI were lower than those of BZD. Additional researches and efforts are required to improve antidepressant drug therapy for neurologic disorders such as AD, PD and VD.

• Research in Community and Public Health Nursing
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• v.11 no.2
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• pp.538-555
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• 2000

The purpose of this study, in which 573 students from 2 high schools in Kang Nung city participated was to identify the attitude and experience of sexual harassment. This information will provide useful data, and promote a more systematic sexual harassment education program. The subjects of this study were 278 male students and 295 female students. The data was collected from September 25 to October 6. 2000. The data was analyzed using the statistical Computer package. SPSS to manipulate the data along with frequency, percentage, and mean t-test. The results from this study were summarized as follows. 1. The results from this comparison between two groups were significant in their attitude on sexual harassment(t=-2.26. p=0.024). Female students had higher scores than male students. 2. As a cause of sexual harassment. 'A man's misjudgement regarding a women as sexual objects(n=130: 22.7%)'. 'Patriarchal system of unequal distribution of power and status between the sexes(n=105: 18.3%)'. 'The effect of sexual stimulatives. (pornography. pornovideo. TV program ect.)(n=89: 15.5%)'. 3. As a countermeasure for prevention, 'Punishment, law and regulation of the sexual harasser(n = 151; 26.4%)', 'A preventive education of sexual harassment in adolescence (n = 125: 21.8%)'. 'Reformation of gender inequality and sex discrimination in the socio-structure(n=76; 13.3%)'. 4. Out of 573 students who participated in this study, 209(36.5%) students reported experiencing an incident of sexual harassment. For 278 males who participated in this study, 88(31.7%) had experienced an incident of sexual harassment. For the 295 females who participated in this study, 121(41.0%) had experienced an incident of sexual harassment. The type of sexual harassment is reported physical sexual harassment(n = 248: 40.5%), verbal sexual harassment(n = 226; 36.7%), and visual sexual harassment(n=139: 22.6%). 5. Their age in which they had experienced harassment was usually 'after 16 years of age(n=122: 58.4%)'. The age of harassers were mostly teenagers(n=112; 53.6%). The relationship to the with sexual harasser was a stranger (n=85; 40.7%), or a friend(n=78: 37.3%). After the incident of sexual harassment occurred, some students informed friends (n=114: 54.5%), 63(30.1%) told no one. Male students' feelings after the experienced harassment ranged from: 'be interesting', 'be pleasant'. Female students' feelings after the experienced harassment ranged from; 'be surprised', 'get a shock', 'fear', 'shame'.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.5C
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• pp.393-402
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• 2012

In this study, we propose a signal processing algorithm to measure the arousal level of a human subject using a PPG(Photoplethysmography) sensor. From the measured PPG signals, the arousal level is determined by PPI(Pulse to Pulse Interval) and discrete-time signal processing. We ran psychophysical experiments displaying visual stimuli on TV display while measuring PPG signal from a finger, where the nature landscape scenes were used for restorative effect, and the urban environments were used to stimulate the stress. However, the measured PPG signals may include noise due to subject movement and measurement error, which results in incorrect detections. In this paper, to mitigate the noise impact on stimulus detection, we propose a detecting algorithm using digital signal processing methods and statistics of measured signals. A filter is adopted to remove a high frequency noise and adaptively designed taking into account the statistics of the measured PPG signals. Moreover we employ a hysteresis method to reduce the distortion of PPI in decision of emotional. Via experiment, we show that the proposed scheme reduces signal noise and improves stimulus detection.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.11
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• pp.1178-1185
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• 2004

In the atmosphere of $N_2$ gas, BaZ $r_{0.08}$ $Ti_{0.92}$ $O_3$ polycrystal was grown by floating zone technique using BaZ $r_{0.08}$ $Ti_{0.92}$ $O_3$ ceramics as a feed and SrTi $O_3$(1l0) single cystal as a seed. The dielectric constant and loss at 10 kHz, 100 kHz, and 1 MHz for the as-grown sample were measured as a function of temperature in the temperature range between -10$0^{\circ}C$ and 150 $^{\circ}C$ to find a dielectric peak with frequency dispersion at Curie point. The hysteresis loop showed that the grown sample had very small polarization which was 0-0.01 $\mu$C/$\textrm{cm}^2$ for the applied dc-electric fields from -7 kV/cm to +7 kV/cm. However, the normal hysteresis loop was appeared after oxygen annealing. The electric-field dependence of the dielectric constant for both the as-grown and the post-annealed samples was studied by measuring the dielectric constants as a function of the biased-electric fields and their tunability was figured out from it at room temperature(27 $^{\circ}C$) and cryotemperature( -73$^{\circ}C$). Tunability for the as-grown sample was 51 % and the figure of merit 20.4 at 10kHz with the biased electric-field of 12 kV/cm. The tunability for the grown sample may be increased up to 80 % if the electric field of 25 kV/cm is applied. Tunability for the post-annealed sample was 41 % and the figure of merit 10.3 at 10 kHz with the biased electric-field of 12 kV /cm. Post-annealing improved the crystallinity of the as-grown sample but decreased its tunability.ability.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.13 no.8
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• pp.754-763
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• 2002

This paper discusses the improved power performances of the size-reduced amplifier using defected ground structure (DGS). The slow-wave effect and enlarged electrical length occur due to the additional equivalent circuit elements of DGS. Using these properties, it is possible to reduce the length of transmission lines in order to keep the same original electrical lengths by inserting DGS on the ground plane. The matching and performances of the amplifier are preserved even after DGS patterns have been inserted. While there is no loss in the size-reduced transmission lines at the operating frequency, but there exists loss to some extent at harmonic frequencies. This leads to the more excellent inherent capability of harmonic rejection of the size-reduced amplifier. Therefore, it is expected tile harmonics of the size-reduced amplifier are smaller than those of the original amplifier. The measured second harmonic, third order intermodulation distortion (IMD3), and adjacent channel power ratio (ACPR) of the size-reduced amplifier are smaller than those of the original amplifier by 5 dB, 2~6 dB, and 1~4 dB, respectively, as expectation.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.4
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• pp.973-981
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• 2007

In the present study, we investigated the antiproliferative activity of the water extract of Samgibopae-tang (SGBPT) in NCI-H460 and A549 non-small-cell lung cancer cell lines. We found that exposure of A549 cells to SGBPT resulted in the growth inhibition in a dose-dependent manner as measured by MTT assay, however SGBPT did not affect the growth of NCI-H460 cells. The antiproliferative effect by SGBPT treatment in A549 cells was associated with morphological changes such as membrane shrinking and cell rounding up. SGBPT treatment did not induce the cell cycle arrest in both cell lines, however the frequency of sub-G1 population was concentration-dependently increased by SGBPT treatment in A549 cells. SGBPT treatment partially induced the expression of tumor suppressor p53 in A549 cells and the expression of cyclin-dependent kinase inhibitor p21(WAF1/CIP1) was markedly increased in both transcriptional and translational levels in A549 cells. The up-regulation of p21 by SGBPT occurred in a similar a concentration dependent manner to that observed with the inhibition of cell viability and induction of sub-G1 population of the cell cycle. However SGBPT treatment did not affect other growth regulation-related genes such as early growth response-1 (Egr-1), nonsteroidal anti-inflammatory drug-activated gene-1 (NAG-1), inducible nitric oxide synthease (iNOS), cyclooxygenases (COXs), telomere-regulatory factors in A549 as well as NCI-H460 cells. Taken together, these findings suggested that SGBPT-induced inhibition of human lung carcinoma A549 cell growth was aoosciated with the induction of p21 and the results provided important new insights into the possible molecular mechanisms of the anti-cancer activity of SGBPT.

• Environmental Mutagens and Carcinogens
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• v.26 no.4
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• pp.125-132
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• 2006

Previous studies showed that epigallocatechin gallate(EGCG) have substantial effects of suppressing the N-methyl-N'-nitro-N-nitrosoguanidine(MNNG)-initiated cell transformation process on the bases of foci formation frequency and loss of anchorage dependency. In this study we tried to clarify the molecular mechanism of suppressing the cell transformation process. Mouse cell line balb/c 3T3 A31-1-1 was exposed 2 days to MNNG followed by 15 days 12-O-tetradecanoylphorbol-13-acetate(TPA) treatment for our transformation process. EGCG was added after the time point of 24 hours exposure to TPA and incubated for 19 days. 2029 genes were selected in our transformation process that showed fold change value of 1.5 or more in the microarray gene expression analysis covering the mouse full genome. These genes were found to be involved mainly in the cell cycle pathway, focal adhesion, adherens junction, TGE-$\beta$ signaling, apoptosis, lysine degradation, insulin signaling, ECM-receptor interaction. Among the genes, we focused on the 631 genes(FC>0.5) reciprocally affected by EGCG treatment. Our study suggest that EGCG down-regulate the gene expressions of up stream signaling factors such as nemo like kinase with MAPK activity and PI3-Kinase, Ras GTPase and down stream factors such as cyclin D1, D2, H, T2, cdk6.