• Journal of Ocean Engineering and Technology
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• v.25 no.2
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• pp.67-72
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• 2011

This study had the goal of investigating the effect of the curvature along the heating line on the transverse angular distortion of plates having an initial curvature from line heating. A thermo-elasto-plastic analysis was carried out using 54 models with various radii of curvature, plate thicknesses, and heating speeds. The results show the effect of the curvature along the heating line on the angular distortion in relation to changes in the magnitudes of the curvature, heating speed, and plate thickness. The present numerical results show that the time history of the angular distortion after cooling and reaching the final deformed shape for a plate having an initial curvature is quite different from that of a flat plate. This emphasized the importance of considering the curvature effect on the transverse angular distortion. From the viewpoint of the curvature effect on the deformation, it has been seen that the curvature does not affect the transverse shrinkage. In this study the predicting formula for the transverse angular distortion was derived through a regression analysis. It showed that as the curvature increased, the angular distortion was reduced because of the higher bending rigidity at the same heat input parameter, and the peak points moved toward the origin as the curvature increased.

• Clinical and Experimental Pediatrics
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• v.64 no.3
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• pp.123-129
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• 2021

Background: The use of indwelling central venous access devices (CVADs) in children can result in complications such as infection, occlusion, and dislodgement. Purpose: To evaluate whether reinforcing CVAD care bundles by using a regular direct feedback system could reduce such complications in children. Methods: The intervention in this retrospective interrupted time-series study was initiated in January 2019. The study was divided into the preintervention (October-December 2018), 3-month postintervention (January-March 2019), and 6-month postintervention (April-June 2019) phases. Risk difference and Poisson regression analyses were used to illustrate the effectiveness of the intervention. Results: The hospital-wide central line-related bloodstream infection rate decreased from 10.0/1,000 catheter-days to 4.5/1,000 catheter-days at 3-month postintervention (P=0.39) and to 1.4/1,000 catheter-days at 6-month postintervention (P=0.047). The central line occlusion rate significantly decreased from 30% to 12.8% (P=0.04) and 8.3% (P=0.002) at 3 and 6 months, respectively. Approximately 7% of CVADs became dislodged during the preintervention phase versus 8.5% (P=0.364) and 3.3% (P=0.378) at 3 and 6 months, respectively. Conclusion: Reinforcing CVAD care bundles with direct feedback could significantly decrease CVAD-associated complications in terms of infection at 6-month postintervention, and occlusion at 3- and 6-month postintervention. Thus, reinforcement and regular direct feedback might improve care quality in children with CVADs.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.3
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• pp.932-951
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• 2021

The effectiveness of testing in Model-based Testing (MBT) for Software Product Line (SPL) can be achieved by considering fault detection in test case. The lack of fault consideration caused test case in test suite to be listed randomly. Test Case Prioritization (TCP) is one of regression techniques that is adaptively capable to detect faults as early as possible by reordering test cases based on fault detection rate. However, there is a lack of studies that measured faults in MBT for SPL. This paper proposes a Test Case Prioritization (TCP) approach based on dissimilarity and string based distance called Last Minimal for Local Maximal Distance (LM-LMD) with Dice-Jaro-Winkler Dissimilarity. LM-LMD with Dice-Jaro-Winkler Dissimilarity adopts Local Maximum Distance as the prioritization algorithm and Dice-Jaro-Winkler similarity measure to evaluate distance among test cases. This work is based on the test case generated from statechart in Software Product Line (SPL) domain context. Our results are promising as LM-LMD with Dice-Jaro-Winkler Dissimilarity outperformed the original Local Maximum Distance, Global Maximum Distance and Enhanced All-yes Configuration algorithm in terms of Average Fault Detection Rate (APFD) and average prioritization time.

• Journal of Environmental Health Sciences
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• v.30 no.3
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• pp.191-206
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• 2004

The present study investigated the hypothesis that a extremely low frequency magnetic field partially suppresses the synthesis of melatonin in a group of 28 primary schoolchildren living nearby and 60 primary schoolchildren aged 12 years living far away from overhead transmission power lines from December 2003 to April 2004 in Seoul, Korea. The mean personal exposure levels of the primary schoolchildren living nearby overhead transmission power line were 0.37 ${\mu}$T, whereas the value for the primary schoolchildren living away from overhead transmission power line 0.05 mT. From simple analyses, the mean melatonin levels in the primary schoolchildren living nearby were lower than away from overhead transmission power line, but not statistically significant differences in the levels of the melatonin (p=0.2421), whereas the statistically significant differences in the levels of the melatonin related to the distance from residence to power line less and more than 100 m by cut-off point (p=0.0139). In multiple linear regression analyses, distance from residence to power line (p=0.0146) and dietary habit about burned meat (p=0.0170) proved to be significant risk factors in the mean nocturnal melatonin levels in the primary schoolchildren. In conclusion, these results demonstrate that urinary levels of nocturnal melatonin are not altered in primary schoolchildren exposed to extremely low frequency magnetic field(ELF-MF) at overhead transmission power line.

• The Journal of the Acoustical Society of Korea
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• v.29 no.2
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• pp.118-124
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• 2010

In this paper, design parameters of dynamic vibration absorber, which is used to reduce bending vibrations of a vehicle drive line, is optimized. For obtaining the correct dynamic response characteristics, a flexible-body drive line is made by applying the flexibility data extracted from vibration analysis of propeller shafts to the drive line dynamic model. Inner tube mass, rubber stiffness and rubber damping coefficient of the dynamic vibration absorber are taken as design parameters for optimization. To minimize the vertical acceleration of the drive line, a second-order regression equation of the objective function is generated by performing the central composite experimental design with 3 factors, 2 levels and 15 test runs. And the design parameters of the dynamic vibration absorber are determined by using optimization program. The vehicle model with optimized dynamic vibration absorber reduces the vertical acceleration peak of the drive line by 17.1 % in compared with the initial model.

• Physical Therapy Korea
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• v.8 no.3
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• pp.63-76
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• 2001

Many studies have shown that the initial median frequency (MDF) and slope correlate with the muscle fiber composition. This study tested the hypothesis that the initial MDF and slope are fixed, regardless of the interval at which data are collected. MDF data using moving fast Fourier transformation of EMG signals, following local fatigue induced by isotonic exercise, were obtained. An inverse FFT was used to eliminate noise, and characteristic decreasing regression lines were obtained. The regression analysis was done in three different periods, the first one third, first half, and full period, looking at variance in the initial MDF, slope, and fatigue index. Data from surface EMG signals during fatiguing isotonic exercise of the biceps brachii and vastus lateralis in 20 normal subjects were collected. The loads tested were 30% and 60% maximum voluntary contraction (MVC) in the biceps brachii and 40% and 80% MVC in the vastus lateralis. The rate was 25 flexions per minute. There were no significant differences in the initial MDF or slope during the early or full periods of the regression, but there was a significant difference in the fatigue index. Therefore, to observe the change in the initial MDF and slope of the MDF regression line during isotonic exercise, this study suggest that only the early interval need to be observed.

• Journal of Preventive Medicine and Public Health
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• v.7 no.2
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• pp.299-304
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• 1974

The physical status (standing height, body weight, chest girth, sitting height, length of leg, length of thigh, thigh girth, length of crus, length of arm, brachial length, antebrachial girth and skinfold thickness) of 360 healthy middle and high school boys aged between 12 and 17 years in Taegu area was measured and evaluated by means of dispersion. For regression equation and coefficient ofidetermination of each status against standing height were computed. The growth progress of physical status had a tendency to be exponential and, generally, between 13 and 14 years of age the fastest progress was observed. The regression coefficient of body weight against standing height (0.90) was largest and that of skinfold thickness against standing height (0.09) was smallest. In general, the dimension of the regression coefficient was accordant with the dimension of respective physical status. Except in length of thigh and skinfold thickness, coefficient of determination of each physical status against standing height was almost 1 and the regression line could express the relation between standing height and each physical status very satisfactorily. But the regression curve was more desirable for the elucidation of the relation between standing height and skinfold thickness.

• Journal of Broadcast Engineering
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• v.25 no.1
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• pp.48-57
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• 2020

Recently, with the rapid development of image recognition technology, the demand for object analysis in road CCTV videos is increasing. In this paper, we propose a method that can adaptively find the counting line for traffic analysis in road CCTV videos. First, vehicles on the road are detected, and the corresponding positions of the detected vehicles are modeled as the two-dimensional pointwise Gaussian map. The paths of vehicles are estimated by accumulating pointwise Gaussian maps on successive video frames. Then, we apply clustering and linear regression to the accumulated Gaussian map to find the principal direction of the road, which is highly relevant to the counting line. Experimental results show that the proposed method for detecting the counting line is effective in various situations.

• Journal of Global Scholars of Marketing Science
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• v.16 no.3
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• pp.87-106
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• 2006

Importance of on-line community has been increased and also on-line community has been used as an important marketing tool. Fashion companies also considered that on-line community provides opportunities to develop customer relationship and to improve customer loyalty. The purpose of this study is 1) to identify the characteristics of fashion on-line community, 2) to investigate the differences of factors affecting brand loyalty among fashion lifestyle groups. For data collection, on-line survey was conducted for fashion on-line community members in Daum portal site and total 404 subjects were used for this study. Factor analysis, cluster analysis, and regression analysis were used for data analysis. The results of this study were as follow: first, characteristics of fashion on-line community were classified as three factors: 'interactivity', 'information provision' and 'interest provision'. Second, the impact of fashion on-line community characteristics on brand loyalty were found to be significantly different among lifestyle groups. The results from this empirical study provide basic information for strategic planning about fashion on-line community by analyzing characteristics of on-line community users.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.2
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• pp.117-122
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• 2004

The fatigue life in wheels was predicted by simulating the experimental method using Finite-Element analysis. Based on a high frequency fatigue property, calculations of the stresses in wheels were performed by simulating the rotating bending fatigue test. Wheels made of an aluminum alloy(A356.2) were tested using a bending fatigue tester. Results from bending fatigue test showed a linear correlation between bending moment and stress amplitude. Consequently, Finite-Element calculations were performed by a linear analysis. In order to find stress-cycles curves, spoke parts of wheel were tested using a rotary bending fatigue tester. Also, highly accurate Finite-Element analysis requires regression lines and confidence intervals from these results. In conclusion, if the fatigue data related to the material and manufacturing procedure are reliable, the prediction on fatigue lift in wheels can be carried out with high accuracy.