• Journal of the Korean Wood Science and Technology
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• v.39 no.4
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• pp.326-332
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• 2011

Radial variation of sound absorption capability and air permeability of yellow poplar (Liriodendron tulipifera) wood in cross sectional surface and effect of steam explosion treatment were estimated by the two microphone transfer function method and the capillary flow porometry, respectively. The sound absorption coefficients of steam explosion treated wood was higher than those of control wood and these values increased with frequency. Abundant and big vessel may behave as sound absorbing pore observed on the cross sectional surface of yellow poplar wood. The sound absorption coefficients and air permeability of sapwood were higher than those of heartwood for Liriodendron tulipifera.

• Journal of Korean Academy of Nursing
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• v.36 no.7
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• pp.1232-1241
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• 2006

Purpose: The purpose of this study was to examine the effects of cerebral ischemia on Type I(soleus) and Type II(plantaris, gastrocnemius) muscles, and to determine the effects of isometric contraction training by electro- stimulation on Type I and II muscles in cerebral ischemia model rats. Method: Twenty-five male Sprague-Dawley rats were randomly divided into four groups: ST(stroke), STES(stroke+electrostimulation), SH(sham) and SHES (sham+electrostimulation). The ST and STES groups received a transient right middle cerebral artery occlusion operation. The SH and SHES groups received a sham operation. The STES and SHES groups had daily isometric contraction training by electrostimulation(100Hz, 45mA, 7.5V) on hindlimb muscles for 7days. Result: Plantaris and gastrocenmius muscle weight, myofibrillar protein contents of soleus and gastrocnemius, and the muscle fiber cross-sectional area of gastrocnemius in the ST group significantly decreased compared with the SH group. Soleus, plantaris, gastrocnemius muscle weight, myofibrillar protein contents of soleus and gastrocnemius, and the Type I muscle fiber cross-sectional area of soleus and the Type II muscle fiber cross-sectional area of gastrocnemius in the STES group significantly increased compared with the 57 group. Conclusion: Hindlimb muscle atrophy occurs after acute stroke and isometric contraction training by electrostimulation during early stages of a stroke attenuates muscle atrophy of Type I and Type II muscles.

• Imaging Science in Dentistry
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• v.50 no.1
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• pp.37-43
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• 2020

Purpose: The purpose of this study was to evaluate the accuracy of linear measurements in the horizontal and vertical dimensions based on object position and slice inclination in cone-beam computed tomography (CBCT) images. Materials and Methods: Ten dry sheep hemi-mandibles, each with 4 sites (incisor, canine, premolar, and molar), were evaluated when either centrally or peripherally positioned within the field of view (FOV) with the image slices subjected to either oblique or orthogonal inclinations. Four types of images were created of each region: central/cross-sectional, central/coronal, peripheral/cross-sectional, and peripheral/coronal. The horizontal and vertical dimensions were measured for each region of each image type. Direct measurements of each region were obtained using a digital caliper in both horizontal and vertical dimensions. CBCT and direct measurements were compared using the Bland-Altman plot method. P values <0.05 were considered to indicate statistical significance. Results: The buccolingual dimension of the incisor and premolar areas and the height of the incisor, canine, and molar areas showed statistically significant differences on the peripheral/coronal images compared to the direct measurements (P<0.05). Molar area height in the central/coronal slices also differed significantly from the direct measurements (P<0.05). Cross-sectional images of either the central or peripheral position had no marked difference from the gold-standard values, indicating sufficient accuracy. Conclusion: Peripheral object positioning within the FOV in combination with applying an orthogonal inclination to the slices resulted in significant inaccuracies in the horizontal and vertical measurements. The most undesirable effect was observed in the molar area and the vertical dimension.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.19 no.6
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• pp.596-605
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• 2007

The behavior of a non-buoyant turbulent round jet discharging horizontally was investigated experimentally. The instantaneous velocity field of the jet was obtained using the particle image velocimetry (PIV) method and used to calculate the mean velocity field by phase-averaging. This study tested regular waves with a relatively small wave height for a wavy environmental flow. The centerline and cross-sectional velocity profiles were reported to demonstrate the effect of the waves on the jet diffusion in respect of wave height and wave phase. The wave phase effect was studied for three phases: zero-upcrossing point, zero-downcrossing point, trough. From the results, it is found that the centerline velocity decreases and width of the cross-sectional profile increases as the wave height increases. In addition, the self-similarity of the cross-sectional profile appears to break down although the width of each case along the axial distance does not vary significantly. The phase effect is found to be relatively small compared to the wave height effect.

• Journal of the Earthquake Engineering Society of Korea
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• v.18 no.4
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• pp.201-212
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• 2014

The plastic hinge region of RC pier ensures its nonlinear behavior during strong earthquake events. It is assumed that the piers secure sufficient strength and ductility in order to prevent the collapse of the bridge during strong earthquake. However, the presence of a lap-splice of longitudinal bars in the plastic hinge region may lead to the occurrence of early bond failure in the lap-splice zone and result in significant loss of the seismic performance. The current regulations for seismic performance evaluation limit the ultimate strain and displacement ductility considering the eventual presence of lap-splice, but do not consider the lap-splice length. In this study, seismic performance test and analysis are performed according to the cross-sectional size and the lap-splice length in the case of longitudinal bars with lap-splice located in the plastic hinge region of existing RC bridge columns with circular cross-section. The seismic behavioral characteristics of the piers are also analyzed. Based upon the results, this paper presents a more reasonable seismic performance evaluation method considering the lap-splice length and the cross-sectional size of the column.

• Journal of Society of Preventive Korean Medicine
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• v.23 no.2
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• pp.101-115
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• 2019

Objective : This study is aimed to application possibility and status of pattern identification in middle and high school students. Method : This study was cross-sectional study. We recruited 277 students through school doctor program of Seongnam city in 2017. Male students are 66 in middle school, 32 in high school. Female students are 117 in middle school, 62 in high school. For pattern identification, we used the tool of Qui Xui Shui pattern identification in students. Students fill questionnaires in inquiry of pattern identification and Korean medicine doctor diagnosis inspection and palpation of students. Results : Among 277 students, no pattern identification were 114(41.2%). It appeared in the order of phlegm, blood deficinecy, qi deficiency, qi stagnation and qi reversal. Qi deficiency, qi stagnation, qi reversal, blood deficiency and phlegm pattern are statistically significant by gender except blood stagnation. of 277 students, 105 (37.9%) had one more pattern identification. Conclusions : This study showed possibility of Qui Xui Shui pattern for student health management. In the future, large scale follow up study will be needed to clarify the relationship of pattern identification and student's health.

• Nutrition Research and Practice
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• v.16 no.2
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• pp.248-259
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• 2022

BACKGROUND/OBJECTIVES: Adequate nutritional intake is essential for good health and well-being. We aimed to compare the nutrient intake from homemade meals, meals sourced externally ("eating out"), and meals from workplace foodservices, as well as the potential association between foodservices used and nutritional quality among adult Korean workers. SUBJECTS/METHODS: We used data from the Korea National Health and Nutrition Examination Survey, a nationwide cross-sectional survey on the health and nutritional status of the Korean population. Data from 6,845 workers aged 20-64 years were included. A survey on dietary behavior and nutrition was conducted using the 24-h dietary recall method. Nutritional quality was examined using the index of nutritional quality (INQ) score. Higher INQ scores reflected poorer nutritional quality, with insufficient intake of a higher number of nutrients. Multivariate linear regression was used to identify the association between the foodservices used and INQ scores after adjusting for other covariates. RESULTS: We found that foodservice users exhibited a higher 1-day intake of total energy and macronutrients (all P < 0.05) and lower INQ scores (P < 0.01) than non-users. The INQ scores for total daily meals decreased with the frequency of foodservice use (P < 0.01). A significant association was observed between the non-use of foodservices and INQ scores (β = 0.29, P < 0.01) after adjusting for other covariates. CONCLUSIONS: The use of workplace foodservices contributed to higher dietary nutritional quality among workers. This study highlights the importance of expanding the scope of workplace foodservices to promote higher nutritional quality and healthy dietary habits among workers.

• Journal of the Economic Geographical Society of Korea
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• v.24 no.4
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• pp.400-410
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• 2021

This study analyzed the determinants of carbon dioxide emissions through the expanded STIRPAT model using panel data from 16 metropolitan cities and provinces in Korea from 2000 to 2019. After testing cross-sectional dependence and coefficient heterogeneity of panel data, we performed analysis using MG, CCEMG, and AMG estimation methods reflected these characteristics. The results of analysis using the AMG estimation method are as follows. The coefficients of income, population, and energy intensity were statistically significant with a positive sign, but urbanization was statistically insignificant. Reduction of carbon dioxide emissions in Korea can be achieved through an increase in energy efficiency and sustainable economic growth. It is necessary to establish a policy that can contribute to sustainable economic growth by inducing productivity improvement through technology innovation reducing carbon dioxide emissions in the long-term as well as building a low-carbon society through active development of carbon dioxide reduction technology.

• Journal of Space Technology and Applications
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• v.4 no.1
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• pp.62-73
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• 2024

This study analyzed the effectiveness of orbital change through attitude change in nano-satellites operating in low Earth orbit (LEO) without thrusters, focusing on collision avoidance maneuvers. The results revealed that changes in the satellite's cross-sectional area significantly impact its in-track direction, influenced by the aspect ratio of cross-sectional area change and mission altitude. Notably, satellites at lower altitudes demonstrated significant reduction in collision risks with a small amount of attitude change. Through this study, it is judged that the changing the cross-sectional area through attitude maneuver is a sufficiently suitable method in the operation of nano-satellites without thrusters, and is expected to contribute to improving the safety of satellite operations in the New Space era.

• Clinical Nutrition Research
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• v.11 no.4
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• pp.289-301
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• 2022

This study was conducted to evaluate the associations between dietary diversity score (DDS) and cardiovascular risk factors in this population. In this cross-sectional study, 187 patients, aged 18-65 years with pemphigus vulgaris were included. DDS was assessed by a 24-hour dietary recall method. Anthropometric measures and biochemical parameters assessed according to standard protocols. Multivariate linear regression analyses used for detecting any associations between DDS and cardiovascular risk factors. The mean ± standard deviation age and body mass index of studied participants were (46.71 ± 11.49 years) and (27.83 ± 4.39 kg/m²) respectively. Our findings showed that a higher DDS intake was related with higher consumption of vegetables (p = 0.001), dairy products (p < 0.001), cereals (p = 0.002), red and processed meat (p < 0.001), sweets and desserts (p < 0.001). After controlling for confounding variables, the results showed positive associations between DDS and high-density lipoprotein cholesterol (HDL-C, β = 1.87, 95% confidence interval [CI], 0.30-3.45, p = 0.02) and total cholesterol (TC) levels (β = 6.41, 95% CI, 1.62-11.03, p = 0.02) (β = 1.75, 95% CI, 0.20-3.30, p = 0.02). However, there were no associations between DDS and prevalence of obesity and glucose homeostasis. The results of this cross-sectional study showed that DDS might be associated with increased HDL-C and TC. However, further prospective studies are needed to prove these findings.