• Journal of Korean Society of Water and Wastewater
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• v.29 no.6
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• pp.625-632
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• 2015

The study of water environment system using a multivariate analysis in Changnyeong-Haman weir section has been conducted. The purpose of this study is to establish better understanding related water qualities in the Changnyeong-Haman weir section which can provide useful information. The data were consisted of water quality data and algae data including WT(water temperature), pH, DO, EC, COD, SS, T-N, $NH_3-N$, T-P, $PO_4-P$, Chl-a, TOC, d-silica, t-silica, Cyanobacteria, Diatoms, and Green algae. Statistical analyses used in this study were correlation analysis, principal components, and factor analysis. According to correlation analysis on COD and TOC, it revealed that the each value of correlation coefficient was 0.843. On the other result, a negative correlation was observed between diatoms and d-silica. Furthermore, the results of principal component analysis to the overall water quality were classified into four main factors with contribution rate 81.071%.

• Restorative Dentistry and Endodontics
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• v.38 no.2
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• pp.79-84
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• 2013

Objectives: This study aimed to investigate the effect of clinical clerkship-associated achievements, such as performance of procedures at the student clinic, observation, and attitude towards a clerkship, on the objective structured clinical examination (OSCE) scores of dental students graduating in restorative dentistry. Materials and Methods: The OSCEs consisted of two stations designed to assess students' clinical skills regarding cavity preparation for a class II gold inlay and a class IV composite restoration. The clerkship achievements, consisting of the number of student clinical procedures performed, observation-related OSCE, and scores of their attitudes towards a conservative dentistry clerkship, were assessed. Correlation and multiple regression analyses were conducted. Results: The correlation coefficient between the OSCE scores for cavity preparation for a class II gold restoration and clerkship attitude scores was 0.241 (p < 0.05). Regarding a class IV composite restoration, OSCE scores showed statistically significant correlations with the observation (r = 0.344, p < 0.01) and attitude (r = 0.303, p < 0.01) scores. In a multiple regression analysis, attitudes towards a clerkship (p = 0.033) was associated with the cavity preparation for a class II gold inlay OSCE scores, while the number of procedure observations (p = 0.002) was associated with the class IV composite restoration OSCE scores. Conclusions: The number of clinical procedures performed by students, which is an important requirement for graduation, showed no correlation with either of the OSCEs scores.

• Journal of Environmental Science International
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• v.8 no.6
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• pp.639-643
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• 1999

After analyzing the correlation between air pollution and visibility, TSP and $NO_2$ is responsible for poor visibility in Pusan. After analyzing the correlation between meteorological factors and visibility, general pattern of humidity has clear negative correlation. The variation of wind speed has a positive correlation. In order to investigate the cause of poor visibility in Pusan area, the Andersen sampler and PM-2.5 are used to collect and analyze aerosol. This study was carried out to monitor the visibility using Forward scattering meter and to find out the characteristics and the cause of good visibility case and poor visibility case by measuring and analyzing a variety of parameters, such as particle size distributions, chemical compositions, and meteorological conditions in Pusan. According to the analysis of intensive sampling, $NO_3^-,NH_4^+$ ion concentration increased together with the mass concentration around $0.5\~2.5{\mu}m$ approximately during the case of poor visibility. $NH_4NO_3,\;NH_4Cl,\;and\;NaCl$ were thought to be the major components of fine particles.

• Journal of Yeungnam Medical Science
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• v.35 no.1
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• pp.63-69
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• 2018

Background: Kinovea software that tracking semi-automatically the motion in video screen has been used to study motion-related tasks in several studies. However, the validation of this software in open field test to assess locomotor activity have not been studied yet. Therefore, this study aimed to examine the reliability and validity of this software in analyzing locomotor activities. Methods: Thirty male Institute Cancer Research mice were subjected in this study. The results examined by this software and the classical method were compared. Test-retest reliability and inter-rater reliability were analyzed with Pearson's correlation coefficient and intraclass correlation coefficient (ICC). The validity of this software was analyzed with Pearson's correlation coefficient. Results: This software showed good test-retest reliability (ICC=0.997, 95% confidence interval [CI]=0.975-0.994, p<0.001). This software also showed good inter-rater reliability (ICC=0.987, 95% CI=0.973-0.994, p<0.001). Furthermore, in three analyses for the validity of this software, there were significant correlations between two methods (Pearson's correlation coefficient=0.928-0.972, p<0.001). In addition, this software showed good reliability and validity in the analysis locomotor activity according to time interval. Conclusion: This study showed that this software in analyzing drug-induced locomotor activity has good reliability and validity. This software can be effectively used in animal study using the analysis of locomotor activity.

• Earthquakes and Structures
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• v.7 no.3
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• pp.365-384
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• 2014

The intensity of a ground motion can be measured by a number of parameters, some of which might exhibit robust correlations with the damage of structures subjected to that motion. In this study, 204 near-fault pulse-type records are selected and their seismic parameters are determined. Time history and damage analyses of a tested 3-storey reinforced concrete frame representing for low-rise reinforced concrete buildings subjected to those earthquake motions are performed after calibration and comparison with the available experimental results. The aim of this paper is to determine amongst several available seismic parameters, the ones that have strong correlations with the structural damage measured by a damage index and the maximum inter-story drift. The results show that Velocity Spectrum Intensity is the leading parameter demonstrating the best correlation, followed by Housner Intensity, Spectral Acceleration and Spectral Displacement. These seismic parameters are recommended as reliable parameters of near-fault pulse-type motions related to damage potential of low-rise reinforced concrete structures. The results also reaffirm that the conventional and widely used parameter of Peak Ground Acceleration does not exhibit a good correlation with the structural damage.

• Geomechanics and Engineering
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• v.17 no.6
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• pp.565-572
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• 2019

Spatial variability is an inherent characteristic of soil, and auto-correlation length (ACL) is a very important parameter in the reliability or probabilistic analyses of geotechnical engineering that consider the spatial variability of soils. Current methods for estimating the ACL need a large amount of laboratory or in-situ experiments, which is a great obstacle to the application of random field theory to geotechnical reliability analysis and design. To estimate the ACL reasonably and efficiently, we propose a micro-structure based numerical simulation method. The quartet structure generation set algorithm is used to generate stochastic numerical micro-structure of soils, and scanning electron microscope test of soil samples combined with digital image processing technique is adopted to obtain parameters needed in the QSGS algorithm. Then, 2-point correlation function is adopted to calculate the ACL based on the generated numerical micro-structure of soils. Results of a case study shows that the ACL can be estimated efficiently using the proposed method. Sensitivity analysis demonstrates that the ACL will become stable with the increase of mesh density and model size. A model size of $300{\times}300$ with a grid size of $1{\times}1$ is suitable for the calculation of the ACL of clayey soils.

• ETRI Journal
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• v.41 no.5
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• pp.637-647
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• 2019

Separating highly correlated users can reduce the loss caused by spatial correlation (SC) in multiuser multiple-input multiple-output (MU-MIMO) systems. However, few accurate analyses of the loss caused by SC have been conducted. In this study, we define signal-to-interference-plus-noise ratio (SINR) loss to characterize it in multiuser multiple-input single-output (MU-MISO) systems, and use coefficient of correlation (CoC) to describe the SC between users. A formula is deduced to show the accurate relation between SINR loss and CoC. Based on this relation, we propose a user selection method that utilizes CoC to minimize the average SINR loss of users in massive MU-MISO systems. Simulation results verify the correctness of the relation and show that the proposed user selection method is very effective at reducing the loss caused by SC in massive MU-MISO systems.

• Journal of The Korean Society of Integrative Medicine
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• v.12 no.1
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• pp.161-169
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• 2024

Purpose : This study investigated the correlation between social support and older people's quality of life. Methods : We conducted a questionnaire survey with 350 older participants and analyzed 320 completed surveys. The collected data were analyzed using SPSS 25.0 for Windows. The general characteristics of the participants and quality of life subdomains were analyzed using descriptive statistics and frequency analyses. Furthermore, the differences between the subdomains of social support and quality of life were analyzed using independent t-tests and a one-way ANOVA. Post-hoc tests were performed using the Scheffé test. A significance level of α=.05 was used to verify statistical significance. Results : Upon examining the sub-domain level of social support and considering general characteristics, it was found that older age correlates with increased dependency among patients with associated diseases (p<.05). Similarly, an investigation into participants' quality of life at the subdomain level, considering general characteristics, revealed higher correspondence to lower quality of life (p<.05). Differences emerged between social support and quality of life among older individuals, with a negative correlation observed between the two (p<.05). Conclusion : This study suggests the importance of actively supporting older people with chronic diseases who experience emotional and psychological instability. It advocates for promoting the use of various services, including visiting medical services, convalescent care, and assistance, to meet their needs effectively.

• Journal of the Korean Society of Clothing and Textiles
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• v.36 no.1
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• pp.36-45
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• 2012

This study locates factors that affect the intention to use fashion SNS (social network service) and intention for word-of-mouth on fashion SNS. Independent variables were fashion shopping orientation, attitude toward innovative products, fashion leadership, and demographics. A questionnaire method was used to collect data on college students while factor analyses, multiple regression, $x^2$ analyses, and Pearson correlation coefficients were applied in analyzing data. Factor analyses resulted in four factors for fashion shopping orientation, three on attitude toward innovative products and two on fashion leadership. Multiple regression analyses showed that information compatibility of attitude toward innovative products had a significant impact on two models of intention to use fashion SNS and two models of intention for word-of-mouth on fashion SNS. Opinion leadership and gender were significant factors for two models of intention to use fashion SNS, which means that women are likely to have more intention to use fashion SNS. Meanwhile, fashion innovativeness was found to be a significant factor on two models of intention for word-of-mouth on fashion SNS. Shopping orientation factors were not important for any model. $x^2$ analyses showed that women rather than men wanted more information on online fashion shows, general fashion information, and user participation programs. Fashion major students wanted more information on online fashion shows and user participation programs than non-fashion major students.

• Computers and Concrete
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• v.12 no.6
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• pp.803-818
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• 2013

In this study, analytical and experimental modal analyses of a scaled bridge model are carried out to extract the dynamic characteristics such as natural frequency, mode shapes and damping ratios. For this purpose, a scaled bridge model is constructed in laboratory conditions. Three dimensional finite element model of the bridge is constituted and dynamic characteristics are determined, analytically. To identify the dynamic characteristics experimentally; Experimental Modal Analyses (ambient and forced vibration tests) are conducted to the bridge model. In the ambient vibration tests, natural excitations are provided and the response of the bridge model is measured. Sensitivity accelerometers are placed to collect signals from the measurements. The signals collected from the tests are processed by Operational Modal Analysis; and the dynamic characteristics of the bridge model are estimated using Enhanced Frequency Domain Decomposition and Stochastic Subspace Identification methods. In the forced vibration tests, excitation of the bridge model is induced by an impact hammer and the frequency response functions are obtained. From the finite element analyses, a total of 8 natural frequencies are attained between 28.33 and 313.5 Hz. Considering the first eight mode shapes, these modes can be classified into longitudinal, transverse and vertical modes. It is seen that the dynamic characteristics obtained from the ambient and forced vibration tests are close to each other. It can be stated that the both of Enhanced Frequency Domain Decomposition and Stochastic Subspace Identification methods are very useful to identify the dynamic characteristics of the bridge model. The first eight natural frequencies are obtained from experimental measurements between 25.00-299.5 Hz. In addition, the dynamic characteristics obtained from the finite element analyses have a good correlation with experimental frequencies and mode shapes. The MAC values obtained between 90-100% and 80-100% using experimental results and experimental-analytical results, respectively.