• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.39 no.1
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• pp.44-49
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• 2003

Masan Bay is one of the most heavily polluted bay in Korea owing to the large industrial complex and urban area. Water transparency, Secchi depth in meter, was observed 33 times totally at four sites during 1995 through 2002 and analysed statistically. The range was 0.2∼7.2m, mean 204m, and variation coefficient 60% in totally. Roughly speaking, monthly mean showed lower value April or July than other months. Seasonal mean showed lower in spring or summer than other seasons. Yearly mean was lowest in '95 and '98 during 7 years. Each sampling site showed a different patterns by the monthly, seasonal or yearly transparencies. Inner bay area, S1 site, showed lowest transparency and highest variation coefficient owing to the streamlets and urban area. And it was supposed that one of the important factor affecting different transparency distribution of most seaward site, S4 site, among four sites in the Masan Bay may be the underwater effluents of urban sewage water treated.

• Journal of Korean Society on Water Environment
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• v.33 no.1
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• pp.51-62
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• 2017

The purpose of this study is to evaluate on the applicability of Load Duration Curve (LDC) method using Maintenance of Variance Extension types 2 method and sampling data for efficient total maximum daily loads at the Nakbon-A unit watershed in Korea. The LDC method allows for characterizing water quality data such as BOD, TOC, T-N and T-P in this study at different flow regimes(or quarters). BOD usually exceeded the standard value (exceedance probability 50%) at low flow zone. On the other hand, TOC, T-N, T-P usually exceeded the standard value at dry and low flow zone. Seasonally all water quality variables usually exceeded the standard value at Q1(Jan-Mar) and Q2(Apr-Jun) zones. Improvement of effluent control from wastewater treatment plants are effective to improve BOD and T-P.

• Child Health Nursing Research
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• v.15 no.3
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• pp.314-324
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• 2009

Purpose: This study was done to test the reliability and validity of the Korean parent as a teacher (KPAAT) inventory for a group of parents of preschoolers. Methods: For this methodological study with 187parents were recruited from October to December, 2004 using convenience sampling. Self-report questionnaires measured level of child-rearing attitude. Internal consistency reliability was assessed with Cronbach's alpha coefficients. Construct validity of KPAAT inventory was analyzed using item analyses and factor analysis. Statistical analysis was done using SPSS Program Version 14.0. Results: The Cronbach's alpha coefficient for the KPAAT inventory was 0.881. For item analyses, inter-item correlation coefficients were -0.029${\sim}$0.781. Corrected item-total correlation coefficients were 0.012-0.737. Item-to"subscale correlation coefficients ranged from 0.509 to 0.817. Subscale-to-total correlation coefficients were 0.965, 0.711, respectively. Orthogonal varimax rotation of the 85 items in 16 areas of the KPAAT inventory, showed two factors, positive parenting attitude and negative parenting attitude. These two factors explained 48.2% of the total variance. Conclusion: In the original KPAAT inventory six factors were identified through factor analysis, however, in this study only two factors were extracted. Whereas, internal consistency reliability was within an acceptable range, these results suggest additional studies are needed to improve the validity of the KPAAT inventory.

• Journal of the Korean Society for Railway
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• v.13 no.3
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• pp.304-308
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• 2010

This paper presents a methodology for identifying track irregularity using a wavelet transfer function. An equivalent wavelet SISO (single-input single-output) transfer function is defined by the measured track geometry and the acceleration data measured at a bogie of a train. All the measured data with various sampling frequencies were rearranged according to the constant 25cm reference recording distance of the track recording vehicle used in the field. Before applying the wavelet transform, measured data were regressed by eliminating those out of the range. The inverse wavelet transfer function is also formulated to estimate track geometry. The closeness of the estimated track geometry to the actual one is evaluated by the coherence function and also by FRF (frequency response function). A track irregularity index is defined by comparing the variance of the estimation error from the intact condition and that from the current condition. A simulation study has been carried out to examine the proposed algorithm.

• Journal of Plant Biology
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• v.15 no.4
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• pp.1-12
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• 1972

To study on the annual height growth of Pinus densiflora within natural pine stands in central Korea, twenty two pure closed Pinus densiflora stands were selected subjectively in the west-central region of Korea. In each stand twenty trees were chosen randomly. For each tree, abotu ten to fifteen measurements of internodal lengths were made from leader top to trunk base. A total of one hundred thirty four soil samples was collected. Each soil sample was bulked with three subsamples. The ranges of the growth measurements per stand, per tree and per observation were 14.9-35.4cm, 9.0cm-54.4cm and 2.4cm-69.0cm respectively. The total mean value was 23.5cm. The Student-Newman-Keul's tests for the multiple comparison among the mean values of the height growth per stand were very highly significant. The resutls of the analysis of variance of the height growth data for the selected fifteen stands among the twenty two stands indicate that sampling efficiency might be increased to 744% if measurement of the growth were made on fifteen trees per stand from twenty stands instead of twenty trees per stand from fifteen stands. The annual height growths of Pinus densiflora and Pinus koraiensis for the period from 1960 to 1968 were 21.74$\pm$5.29cm (10) and 20.56$\pm$5.59cm (10) respectively. The total means of easily-soluble phosphorus, total nitrogen, loss on ignition and pH for the soil samples were 2.8 ppm, 0.09%, 5.4% and 4.7 respectively. The ranges of those amounts were 18.7-1.7ppm, 0.17-0.05%, 11.6%-3.1%, 3.9-5.1 respectively. The relationship of the annual height growth of P. densiflora to soil was studied in terms of standard partial multiple regression. Among soil properties such as non-capillary pore space, capillary pore space, maximum field capacity, loss on ignition, soil reaction, total nitrogen and easily-soluble phosphoros investigated, the easily soluble phosphorus in one analysis and loss on ignition and soil reaction in the other analysis seem to have significant positive influence on the annual height growth.

• Journal of Ginseng Research
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• v.40 no.4
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• pp.375-381
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• 2016

Background: We evaluated the drug interaction profile of Red Ginseng (RG) with respect to the activities of major cytochrome P450 (CYP) enzymes and the drug transporter P-glycoprotein (P-gp) in healthy Korean volunteers. Methods: This article describes an open-label, crossover study. CYP probe cocktail drugs, caffeine, losartan, dextromethorphan, omeprazole, midazolam, and fexofenadine were administered before and after RG supplementation for 2 wk. Plasma samples were collected, and tolerability was assessed. Pharmacokinetic parameters were calculated, and 90% confidence intervals (CIs) of the geometric mean ratios of the parameters were determined from logarithmically transformed data using analysis of variance after RG administration versus before RG administration. Results: Fourteen healthy male participants were evaluated, none of whom were genetically defined as poor CYP2C9, 2C19, and CYP2D6 metabolizers based on genotyping. Before and after RG administration, the geometric least-square mean metabolic ratio (90% CI) was 0.870 (0.805-0.940) for caffeine to paraxanthine (CYP1A2), 0.871 (0.800-0.947) for losartan (CYP2C9) to EXP3174, 1.027 (0.938-1.123) for omeprazole (CYP2C19) to 5-hydroxyomeprazole, 1.373 (0.864-2.180) for dextromethorphan to dextrorphan (CYP2D6), and 0.824 (0.658-1.032) for midazolam (CYP3A4) to 1-hydroxymidazolam. The geometric mean ratio of the area under the curve of the last sampling time ($AUC_{last}$) for fexofenadine (P-gp) was 0.963 (0.845-1.098). Administration of concentrated RG for 2 wk weakly inhibited CYP2C9 and CYP3A4 and weakly induced CYP2D6. However, no clinically significant drug interactions were observed between RG and CYP and P-gp probe substrates. Conclusion: RG has no relevant potential to cause CYP enzyme- or P-gp-related interactions.

• Safety and Health at Work
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• v.5 no.2
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• pp.80-85
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• 2014

Background: Currently available questionnaires for evaluating the quality of worklife do not fully examine every factor related to worklife in all cultures. A tool in Thai is therefore needed for the direct evaluation of the quality of worklife. Our aim was to translate the Work-related Quality of Life Scale-2 (WRQLS-2) into Thai, to assess the validity and reliability of the Thai-translated version, and to examine the tool's accuracy vis-$\grave{a}$-vis nursing in Thailand. Methods: This was a descriptive correlation study. Forward and backward translations were performed to develop a Thai version of the WRQLS. Six nursing experts participated in assessing content validity and 374 registered nurses (RNs) participated in its testing. After a 2-week interval, 67 RNs were retested. Structural validity was examined using principal components analysis. The Cronbach's alpha values were calculated. The respective independent sample t test and intraclass correlation coefficient were used to analyze known-group validity and test-retest reliability. Multistate sampling was used to select 374 RNs from the In- and Outpatient Department of Srinagarind Hospital of the Khon Kaen University (Khon Kaen, Thailand). Results: The content validity index of the scale was 0.97. Principal components analysis resulted in a seven-factor model, which explains 59% of the total variance. The overall Cronbach's alpha value was 0.925, whereas the subscales ranged between 0.67 and 0.82. In the assessment results, the known-group validity was established for the difference between civil servants and university employees [F (7.982, 0.005) and t (3.351; p < 0.05)]. Civil servants apparently had a better quality worklife, compared to university employees. Good test-retest reliability was observed (r = 0.892, p < 0.05). Conclusion: The Thai version of a WRQLS appears to be well validated and practicable for determining the quality of the work-life among nurses in Thailand.

• Journal of Species Research
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• v.2 no.2
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• pp.159-166
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• 2013

Typical of large, oligotrophic lakes, Lake H$\ddot{o}$vsg$\ddot{o}$l, Mongolia, exhibits complex morphometry which should support a spatially heterogeneous community of benthic macroinvertrates. The lake also exhibits a broad range of land uses. Based on the variation in land use and complex physical habitat of the lake (e.g. substrate variation and presence of affluent streams in bays), we asked two questions. First, does density of total benthic macroinvertebrates vary between different bays in Lake H$\ddot{o}$vsg$\ddot{o}$l? Second, does density of individual benthic taxa vary by bay? Samples collected in 1997, the last year for benthic sampling of the lake, were designed to test for variation in macroinvertebrate density between bays and can now be used to establish baseline variation in density for future studies. A total of 56 Ponar grab samples were analyzed from six bays in Lake H$\ddot{o}$vsg$\ddot{o}$l. Results of a general linear model analysis of variance showed that total density of macroinvertebrates varied only slightly between bays of the lake, but that most individual taxa showed significant variation between bays. Variation in density for most taxa was linked to substrate composition rather than other geographic or physical variables in the lake. Recent increases in grazing intensity and ecotourism along the shores should be managed to reduce the nutrient load into the lake to avoid impairment of the benthic biota of this unique, ancient ecosystem.

• Korean Journal of Clinical Pharmacy
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• v.10 no.1
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• pp.25-29
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• 2000

Bioequivalence of cisapride-containing $Cisaplus^{(R)}$ tablets (Daewoong Co.) to reference $Prepulsid^{(R)}$ tablets (Janssen Co.) was evaluated according to the guidelines of Korea Food and Drug Administration (KFDA). Sixteen healthy volunteers were divided randomly into two groups and administered orally at a cisapride dose of 10 mg in a $2\times2$ crossover design. There was a 1-week washout period between the treatments. Blood samples were taken at predetermined time intervals for 48 hr and the plasma cisapride concentrations were determined by an HPLC with UV detector. The area under the plasma drug concentration-time curve (AUC) was caltulated from time zero to the last sampling time by a linear trapezoidal method. The maximum observed plasma drug concentration ($C_{max}$) and the time to $C_{max}\;(T_{max})$ were estimated directly from the drug concentration-time data. Analysis of variance (ANOVA) showed that the apparent differences for AUC, $C_{max}\;and\;T_{max}$ were $-7.52\%,\;-8.91\%\;and\;-15.55\%$, respectively. The minimum detectable differences for AUC, $C_{max}\;and\;T_{max}$ between formulations were $14.52\%,\;11.57\%\;and\;28.00\%$ respectively, at $\alpha=0.05\;and\;1-\beta=0.8\;levels.\;The\;90\%$ confidence intervals for AUC, $C_{max}\;and\;T_{max}\;were\;-16.00\sim0.97\%,\;-15.67\sim-2.15\%\;and\;-31.88\%\sim0.84\%$, respectively. These results satisfy the bioequivalence criteria of KFDA guidelines, indicating that the two formulations of cisapride are bioequivalent.

• Research in Community and Public Health Nursing
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• v.16 no.4
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• pp.458-466
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• 2005

Purpose: The purpose of this study was to determine the relation between test anxiety and mental health in adolescents. Method: The subjects were 450 students of two academic high schools in J City, who were selected through convenient sampling. Data were collected through a survey using a structured questionnaire from September 1st to 15th 2005. Collected data were analyzed using SPSS 10.0 for Windows through descriptive analysis, Pearson's Correlation Coefficient, t-test, ANOVA, Scheffe's test and stepwise multiple regression. Result: The mean score of test anxiety was 2.40 (range:1.13-3.81) and that of mental health was 2.77 (range:0.64-5.03). A significant negative correlation was observed between test anxiety and mental health (r=-0.28, p=.000). Test anxiety was significantly different according to adolescents' general characters such as gender (t=-1.98, p=.048), grade (F=3.54, p=.030), school life satisfaction (F=10.73, p=.000) and relationship with the teacher (F=11.60, p=.000). Mental health was significantly different according to adolescents' general characters such as religion (t=2.14, p=.032) and school life satisfaction (F=4.13, p=.017). The most powerful predictor of mental health was test anxiety and it, combined with religion, accounted for 9.0% of variance in mental health in adolescents. Conclusion: Test anxiety and mental health was found to be in a significant negative correlation with each other in adolescents. Therefore, nursing intervention programs for adolescents needs to reduce their test anxiety to improve their mental health.