• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.35 no.1
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• pp.55-62
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• 2017

The SRP (Solar Radiation Pressure) model has always been an issue in the dynamic GPS (Global Positioning System) orbit determination. The widely used CODE (Center for Orbit Determination in Europe) model and its variants have nine parameters to estimate the solar radiation pressure from the Sun and to absorb the remaining forces. However, these parameters show a very high correlation with each other and, therefore, only several of them are estimated at most of the IGS (International GNSS Service) analysis centers. In this study, we attempted to numerically verify the correlation between the parameters. For this purpose, a bi-directional, multi-step numerical integrator was developed. The correlation between the SRP parameters was analyzed in terms of post-fit residuals of the orbit. The integrated orbit was fitted to the IGS final orbit as external observations. On top of the parametric analysis of the SRP parameters, we also verified the capabilities of orbit prediction at later time epochs. As a secondary criterion for orbit quality, the positional discontinuity of the daily arcs was also analyzed. The resulting post-fit RMSE (Root-Mean-Squared Error) shows a level of 4.8 mm on average and there is no significant difference between block types. Since the once-per-revolution parameters in the Y-axis are highly correlated with those in the B-axis, the periodic terms in the D- and Y-axis are constrained to zero in order to resolve the correlations. The 6-hr predicted orbit based on the previous day yields about 3 cm or less compared to the IGS final orbit for a week, and reaches up to 6 cm for 24 hours (except for one day). The mean positional discontinuity at the boundary of two 1-day arcs is on the level of 1.4 cm for all non-eclipsing satellites. The developed orbit integrator shows a high performance in statistics of RMSE and positional discontinuity, as well as the separations of the dynamic parameters. In further research, additional verification of the reference frame for the estimated orbit using SLR is necessary to confirm the consistency of the orbit frames.

• Journal of Korean Society of Transportation
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• v.20 no.1
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• pp.131-139
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• 2002

This study introduces a developed artificial neural networks(ANN) model as a more efficient and reliable prediction model in operating speed Prediction with the 85th percentile horizontal curve of two-way rural highway in the aspect of evaluating highway design consistency. On the assumption that the speed is decided by highway geometry features, total 30 survey sites were selected. Data include currie radius, curve length, intersection angle, sight distance, lane width, and lane of those sites and were used as input layer data of the ANN. The optimized model structure was drawn by number of unit of hidden layer, learning coefficient, momentum coefficient, and change in learning frequency in multi-layer a ANN model. To verify learning Performance of ANN, 30 survey sites were selected while data in obtained from the 20 cites were used as learning data and those from the remaining 10 sites were used as predictive data. As a result of statistical verification, the model D of 4 types of ANN was evaluated as the most similar model to the actual operating speed value: R2 was 85% and %RMSE was 0.0204.

• Journal of Microbiology and Biotechnology
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• v.28 no.11
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• pp.1823-1833
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• 2018

Fluorescence in-situ hybridization (FISH) is a common and popular method used to investigate microbial communities in natural and engineered environments. In this study, two specific 16S rRNA-targeted oligonucleotide probes, CLZ and KCLZ, were designed and verified to quantify the genus Clostridium and the species Clostridium kluyveri. The optimal concentration of hybridization buffer solution for both probes was 30% (w/v). The specificity of the designed probes was high due to the use of pellets from pure reference strains. Feasibility was tested using samples of Chinese liquor from the famed Luzhou manufacturing cellar. The effectiveness of detecting target cells appears to vary widely in different environments. In pit mud, the detection effectiveness of the target cell by probes CLZ and KCLZ was 49.11% and 32.14%, respectively. Quantitative analysis by FISH technique of microbes in pit mud and fermented grains showed consistency with the results detected by qPCR and PCR-DGGE techniques, which showed that the probes CLZ and KCLZ were suitable to analyze the biomass of Clostridium spp. and C. kluyveri during liquor fermentation. Therefore, this study provides a method for quantitative analysis of Clostridium spp. and C. kluyveri and monitoring their community dynamics in microecosystems.

• Journal of Korean Society for Atmospheric Environment
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• v.34 no.2
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• pp.331-341
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• 2018

Hazardous air pollutants(HAPs) in the atmosphere are regulated as major air pollutants in Korea by the Air Pollution Control Act. In order to manage and control HAPs, accurate standards, which are traceable to the International System of Units(SI), are required. In this study, primary standard gas mixtures(PSMs) of volatile organic compounds(VOCs) which are specified as HAPs were developed at $1{\mu}mol/mol$ levels. The selected fourteen VOCs include Benzene, Toluene, Ethylbenzene, m-Xylene, Styrene, o-Xylene, Chloroform, 1,1,2-Trichloroethane, Trichloroethylene, Tetrachloroethylene, 1,1-Dichloroethane, Carbon tetrachloride, 1,3-Butadiene, and Dichloromethane. The HAPs PSMs were gravimetrically prepared in aluminum cylinders and their consistency was verified within the relative expanded uncertainty of 0.71% (k=2). Potential adsorption loss onto the internal surface of cylinders was estimated by cylinder-to-cylinder division method. No adsorption loss was observed within the uncerainty of 0.53%. The long-term stability of the HAPs PSMs was evaluated comparing with freshly prepared HAPs PSMs. The HAPs PSMs were stable for one year within the uncertainty of 0.38%. The final uncertainty of the PSMs was determined by combining the preparation uncertainty, verification uncertainty, and stability uncertainty. Finally, traceable and stable HAPs PSMs at $1{\mu}mol/mol$ levels were developed with the uncertainty of less than 0.76% in high-pressure aluminum cylinders.

• The Journal of Korean Academic Society of Nursing Education
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• v.26 no.1
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• pp.47-55
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• 2020

Purpose: The aim of this study was to examine the validity and reliability of the Korean version of the PTSD scale (K-PTSD) for measuring attitudes and knowledge of PTSD. Methods: A cross-sectional study design was used. The K-PTSD scale consisted of 8 items for attitudes, 8 items for general knowledge of PTSD, and 3 items for knowledge of PTSD treatment; 211 nursing students and paramedic students participated. Content validity, item analysis, and factor analysis were used to examine the construct validity. Criterion validity was tested by using educational experience with PTSD as a criterion. Cronbach's α was used to identify internal consistency reliability in the attitude scale. Results: Construct validity of the K-PTSD was verified by exploratory factor analysis, with factor loadings for attitude ranging from .59 to .84. Criterion validity in comparing knowledge of PTSD (t=2.02, p=.044) and PTSD treatment (t=3.19, p=.022) showed a significant difference according to PTSD educational experience. Cronbach's α for the attitude scale was .79 and .59. Conclusion: The findings suggest that the K-PTSD is a valid and reliable tool that can measure attitudes and knowledge of PTSD among nursing and paramedic students. However, further study is needed to retest the verification of this scale with more diverse participants.

• Journal of the Korea Concrete Institute
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• v.22 no.6
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• pp.761-768
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• 2010

When cracks occur in reinforced concrete structures, a steel carries all tensile force at crack section, while the concrete between cracks carries a part of the tensile force due to bond, so that the steel is less elongated. This is called the tension-stiffening effect, that plays an important role in verification of a serviceability limit state. But it is a complicated work to use a complex strain distribution between cracks, therefore an average strain is used to calculate deflection and crack width. In Eurocode 2, tension-stiffening effect expressed in the first order form or the second order form is used in calculating an average curvature for deflection. In this study for a flexural member deflection and crack width are calculated using various models for the tension-stiffening effect and the results are compared with the values of Eurocode 2 and KCI provisions. As results, the predicted values using the second order form are appeared to be well agreed with the experimental values and it could secure more analytical consistency.

• Journal of Korean Academic Society of Home Health Care Nursing
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• v.22 no.2
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• pp.246-255
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• 2015

Purpose: The study was conducted to develop the Nursing Practice Capacity scale for evaluating achievement of education objectives among students in nursing school. Methods: This was a methodological study. The scale development process included generation of initial items, verification of content validity, selections of secondary items, preliminary study, and extraction of final items. The participants were five graduates 1 to 4 years after graduation (for the preliminary study) and 125 graduates 1 to 4 years after graduation from the nursing school at A University, South Korea. Item analysis, criterion validity, and internal consistency were used to analyze the data. Results: Twenty-six items were selected for the final scale. The scores on the scale were significantly correlated with the Nursing Competency Scale(r=.62, p<.001) and Nursing Performance Scale(r=.63, p<.001). Chronbach's alpha coefficient for the 26 items was .87. Conclusion: The Nursing Practice Capacity scale for evaluating achievement of nursing education objectives has good validity and reliability. The measurement scale can be useful for evaluating the nursing practice capacity of nurses as well as measuring the extent to which graduates have achieved the established education objectives in the education fields.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.45 no.7
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• pp.550-557
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• 2017

Ionospheric delay, which affect the accuracy of GNSS positioning, is generated by electrons in Ionosphere. Solar activity level, region and time could make change of this delay level. Dual frequency receiver could effectively eliminate the delay using difference of refractive index between L1 to L2 frequency. But, Single frequency receiver have to use limited correction such as ionospheric model in standalone GNSS or PRC(pseudorange correction) in Differential GNSS. Generally, these corrections is effective in normal condition. but, they might be useless, when TEC(total electron content) extremely increase in local area. In this paper, monitoring algorithm is proposed for local ionospheric anomaly using multiple reference stations. For verification, the algorithm was performed with specific measurement data in Ionospheric storm day (20. Nov. 2003). this algorithm would detect local ionospheric anomaly and improve reliability of ionospheric corrections for standalone receiver.

• Journal of Gifted/Talented Education
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• v.25 no.4
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• pp.511-528
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• 2015

The development process from creative potential to realized talent is complex and non-linear. This feature of the process stands out more in the process of living a creative life in the long-term rather than in a situation to solve certain problems in the short-term. The purpose of this study is to develop Creativity Path Inventory (CPI) for undergraduate students based on Sawyer's Zigzag Model which is one of creative process theories and to verify reliability and validity of the inventory. Thus, reflecting the characteristics of each stage of the model, this study developed 88 items in 8 factors and finally confirmed 38 items in 7 factors through item analysis and verification process on construct validity. Internal consistency of a total of 38 items in CPI turned out to be .835, confirming the reliability of the inventory and goodness-of-fit index of the final model also demonstrated an appropriate result. CPI with verified reliability and validity will help enable people who want to manifest creativity in view of everyday creativity to realize self-improvement by self-reporting their strengths and weaknesses on their own.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.9
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• pp.4341-4347
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• 2016

Background: Patient safety is one of the key components of nursing care for cancer cases. Valid and reliable context-based instruments are necessary for accurate evaluation of patient safety in oncology units. The aim of the present study was to develop and evaluate the psychometric properties of the Patient Safety Violation Scale in medical oncology units in Iran. Materials and Methods: In this methodological study, a pool of 58 items was generated through reviewing the existing literature. The validity of the 58-item scale was assessed through calculating impact score, content validity ratio, and content validity index for its items as well as conducting exploratory factor analysis. The reliability of the scale was evaluated by assessing its internal consistency and testretest stability. Study sample consisted of 300 oncology nurses who were recruited from thirteen teaching hospitals affiliated to Tehran University of Medical Sciences, Tehran, Iran. Results: Sixteen items were excluded from the scale due to having low impact scores, content validity ratios, or content validity indices. In exploratory factor analysis, the remaining 42 items were loaded on five factors including patient fall, verification of patientidentity, harm during care delivery, delay in care delivery, and medication errors. These five factors explained 62% of the total variance. The Cronbach's alpha of the scale and the test-retest interclass correlation coefficient were equal to 0.933 and 0.92, respectively. Conclusions: The 42-item Patient Safety Violation Scale is a simple and short scale which has acceptable validity and reliability. Consequently, it can be used for assessing patient safety in clinical settings such as medical oncology units and for research projects.