• International Journal of Highway Engineering
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• v.19 no.4
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• pp.27-36
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• 2017

PURPOSES : The purpose of this study is to perform a reliability analysis of the proposed wind load combination which governs the design of support structures of subsidiary road facilities, and to evaluate whether the target reliability of the design is satisfied. METHODS : The statistical estimation method is applied and the design period of the support structure is used to obtain the statistical property of the wind load. In addition, the statistical properties of the strength of support structures are obtained from a literature review and simulation study. Actual support structures are designed by the proposed load combination and are used as the examples to examine if the target reliability is obtained. RESULTS : The result of the reliability analysis performed by using the statistical properties of load and resistance for the support structure in this study indicates that the proposed wind load combination satisfied the target reliability index of the design. Also, the convenience of the design is achieved by adopting the same design wind velocity given in the bridge design code by applying the wind velocity ratio defined for the design period of the support structure. CONCLUSIONS : It is presented that the design using the wind load combination proposed in this study achieved the target reliability index and the design wind load for different design periods can be conveniently defined by applying the velocity ratio proposed in this study.

• Women's Health Nursing
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• v.17 no.4
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• pp.388-394
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• 2011

Purpose: This study was done to evaluate the accuracy and adequacy of research studies reporting statistical testing for mean differences in studies of the Korean Journal of Women Health. Methods: Among articles published in the journal from 2007 to 2009, 75 studies using t-test, $x^2$-test, and ANOVA were identified. The studies were evaluated using structured analysis format for adequacy of research title, accuracy of statistical methods and presentation styles, and errors in reported statistical outcomes. Results: In this study, the research titles generally reflected the purpose of research and study designs. Thus the research titles were quite comprehensive. Also, there was compatibility between the research purpose and research design. Most important though, many errors were identified in the tables of results of the statistical analysis in articles published from 2004 to 2006. Conclusion: Over six years, 2004 to 2009, accuracy and adequacy of research studies has improved in many aspects. In order to enhance the completeness of the published papers and to be an internationally recognized nursing journal, close attention of the researchers, reviewers and editors is necessary to avoid errors and present adequate and accurate research.

• Journal of the Korean association of regional geographers
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• v.22 no.2
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• pp.424-438
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• 2016

In an effort to prevent urban decline and hollowing-out phenomenon and to vitalize stagnant local economy, a new urban regeneration paradigm is on the rise. This study aims to analyze urban decline characteristics using the spatial statistical method and GIS on the basis of decline standards in the Urban Regeneration Special Act, and spatial autocorrelation technique. The Gwangju Metropolitan City was set as a research target, and the decline standards in the Urban Regeneration Special Act - population reduction, business declines, and outworn buildings - were applied as the indicator to secure the objectivity. In particular, this study has a distinctive feature from the other existing ones, as applying GIS and the spatial statistical technique, in a sense to make urban decline characteristics analysis by the spatial autocorrelation technique. The overall analysis procedure was carried out by applying the standards of designating urban regeneration regions, and following the spatial exploratory procedure step by step. Therefore, the spatial statistical method procedure and the urban decline characteristics analysis data being presented in this study, as the results, are expected to contribute to the urban decline diagnosis at the level of metropolitan city, as well as to provide useful information for spatial decision making in accordance with urban regeneration.

• Journal of Korean society of Dental Hygiene
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• v.19 no.2
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• pp.287-295
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• 2019

Objectives: The purpose of this study was to investigate the factors affecting subjective oral symptoms according to the gender of youth from multi-cultural families in Korea using data from the 14th (2018) Korean Youth Health Behavior Survey. Methods: The independent variables used in this study consisted of gender and sweet drink intake. The dependent variable was experience of subjective oral symptoms. Compensation variables consisted of general characteristics of school type, academic performance, economic status, drinking status, smoking status, and number of tooth brushings day before. The subjects of the study were 835 children of multi-cultural families whose parents were foreigners. All statistical analyses were performed by complex samples cross-tabulation analysis and complex samples logistic regression analysis. Statistical analysis was performed using the PASW statistical package 21.0 (Statistical Packages for Social Science Inc., Chicago, IL, USA). A significance level of 0.05 was used for statistical significance. Results: The composite sample logistic regression analysis showed that there was a statistically significant difference between gender and intake of sweet drinks in experience of subjective oral symptoms. Conclusions: These results suggest that factors influence subjective oral symptoms in Korean multi-cultural adolescents. Therefore, I hope that they will be used as basic data for the introduction and development of a customized oral health education program for improving oral health of multi-cultural adolescents.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.1
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• pp.100-108
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• 2021

The purpose of this study is to analyze the reliability index of a design by applying the reduction factor of the recently developed fiber reinforced high strength concrete design guideline(draft). By collecting material and member test data performed for the development of the design guideline(draft), statistical characteristics of material strength and member strength analysis equations are obtained. A simul ation that appl ies the material statistical characteristics and the member anal ysis equation of the design guidel ine(draft) is performed, and the statistical characteristics of the section strength are calculated by combining the statistical characteristics of the analysis equation. Reliability analysis was performed by applying the load combination of the domestic highway bridge design code and concrete structural code, and it was confirmed that the design that applies the reduction factor for materials and members suggested in the design guideline(draft) satisfies the target reliability index.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.39 no.1
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• pp.130-139
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• 2016

The purpose of this paper is to analyze the problems and the sources of defective products and draw improvement plans in a small plastic boat manufacturing process using TOC (Theory Of Constraints) and statistical analysis. TOC is a methodology to present a scheme for optimization of production process by finding the CCR (Capacity Constraints Resource) in the organization or the all production process through the concentration improvement activity. In this paper, we found and reformed constraints and bottlenecks in plastic boat manufacturing process in the target company for less defect ratio and production cost by applying DBR (Drum, Buffer, Rope) scheduling. And we set the threshold values for the critical process variables using statistical analysis. The result can be summarized as follows. First, CCRs in inventory control, material mix, and oven setting were found and solutions were suggested by applying DBR method. Second, the logical thinking process was utilized to find core conflict factors and draw solutions. Third, to specify the solution plan, experiment data were statistically analyzed. Data were collected from the daily journal addressing the details of 96 products such as temperature, humidity, duration and temperature of heating process, rotation speed, duration time of cooling, and the temperature of removal process. Basic statistics and logistic regression analysis were conducted with the defection as the dependent variable. Finally, critical values for major processes were proposed based on the analysis. This paper has a practical importance in contribution to the quality level of the target company through theoretical approach, TOC, and statistical analysis. However, limited number of data might depreciate the significance of the analysis and therefore it will be interesting further research direction to specify the significant manufacturing conditions across different products and processes.

• Computers and Concrete
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• v.15 no.2
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• pp.259-277
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• 2015

The lack of experimental studies on the mechanical behavior of reinforced concrete (RC) haunched beams leads to difficulties in statistical and reliability analyses. This study performs stochastic and reliability analyses of the ultimate shear capacity of RC haunched beams based on nonlinear finite element analysis. The main aim of this study is to investigate the influence of uncertainty in material properties and geometry parameters on the mechanical performance and shear capacity of RC haunched beams. Firstly, 65 experimentally tested RC haunched beams and prismatic beams are analyzed via deterministic nonlinear finite element method by a special program (ATENA) to verify the efficiency of utilized numerical models, the shear capacity and the crack pattern. The accuracy of nonlinear finite element analyses is verified by comparing the results of nonlinear finite element and experiments and both results are found to be in a good agreement. Afterwards, stochastic analyses are performed for each beam where the RC material properties and geometry parameters are assigned to take probabilistic values using an advanced simulating procedure. As a result of stochastic analysis, statistical parameters are determined. The statistical parameters are obtained for resistance bias factor and the coefficient of variation which were found to be equal to 1.053 and 0.137 respectively. Finally, reliability analyses are accomplished using the limit state functions of ACI-318 and ASCE-7 depending on the calculated statistical parameters. The results show that the RC haunched beams have higher sensitivity and riskiness than the RC prismatic beams.

• Korean Journal of Medicinal Crop Science
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• v.24 no.2
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• pp.93-100
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• 2016

Background: A set of logical criteria that can accurately identify and verify the cultivation region of raw materials is a critical tool for the scientific management of traditional herbal medicine. Methods and Results: Volatile compounds were obtained from 19 and 32 samples of Angelica gigas Nakai cultivated in Korea and China, respectively, by using steam distillation extraction. The metabolites were identified using GC/MS by querying against the NIST reference library. Data binning was performed to normalize the number of variables used in statistical analysis. Multivariate statistical analyses, such as Principal Component Analysis (PCA), Partial Least Squares-Discriminant Analysis (PLS-DA), and Orthogonal Partial Least Squares-Discriminant Analysis (OPLS-DA) were performed using the SIMCA-P software. Significant variables with a Variable Importance in the Projection (VIP) score higher than 1.0 as obtained through OPLS-DA and those that resulted in p-values less than 0.05 through one-way ANOVA were selected to verify the marker compounds. Among the 19 variables extracted, styrene, ${\alpha}$-pinene, and ${\beta}$-terpinene were selected as markers to indicate the origin of A. gigas. Conclusions: The statistical model developed was suitable for determination of the geographical origin of A. gigas. The cultivation regions of six Korean and eight Chinese A. gigas. samples were predicted using the established OPLS-DA model and it was confirmed that 13 of the 14 samples were accurately classified.

• Journal of Korean Medicine Rehabilitation
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• v.27 no.4
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• pp.121-130
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• 2017

Objectives This study was designed to investigate the correlation between the gait analysis indices and Lumbar X-ray indicators. Methods 21 cases of patients who received treatment from October 2013 to February 2017 for abnormal posture were analyzed. Three indicators were measured in the lumbar spine X-ray. These indicators include Ferguson's angle, Lumbar lordotic angle, L4-5 IVD angle. Gait analysis indices were estimated by Treadmill Gait Analysis system. The data were analyzed to find out correlation between the gait analysis indices and Lumbar X-ray indicators. Spearman correlation was used. Results Ferguson's angle and Difference of gait balance of front and rear had a negative linear relationship, but there was no statistical significance. Lumbar lordotic angle and Difference of gait balance of front and rear had a negative linear relationship, but there was no statistical significance. L4-5 IVD angle and Difference of gait balance of right and left had a negative linear relationship, but there was no statistical significance. Conclusions Difference of gait balance of front and rear had strong level of a negative linear relationship with Ferguson's angle and Lumbar lordotic angle.

• Journal of Applied Reliability
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• v.10 no.1
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• pp.39-56
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• 2010

Statistical process control (SPC) is a powerful technique for monitoring, managing, analysing and improving the process performance. However, its has limitations such as lack of engineering, statistical skill and training, and lesser importance of activity. To solve the problems, this study proposes an intelligent SPC system using specified agents which are derived through analysis and evaluation of the SPC activities. The activities investigated by the relevant researches are categorized as collection, process analysis, diagnosis, detection, cause analysis and rule generation. Also, the evaluation criteria are established as feasibility of automation, frequency, level and time. The requirements of the agent functions are derived by the evaluation, and the types of customized agents are as data collection, store, analysis, diagnosis, monitoring, alarm and reporting. A prototype SPC system represents that the functions of the proposed agents are successfully validated.