• Structural Engineering and Mechanics
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• v.90 no.6
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• pp.551-568
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• 2024

The present study deals with static and dynamic behaviors including forced vibrations of an elastic rectangular nano plate on the two-parameter foundation. Firstly, the rectangular plate is assumed to be subjected to uniformly distributed and eccentrically applied concentrated loads. The governing equations of the problem are derived by considering the dynamic response of the plate, employing a series of the Chebyshev polynomials for the displacement function and applying the Galerkin method. Then, effects of the non-essential boundary conditions of the plate, i.e., the boundary conditions related to the shearing forces, the bending moments and the corner forces, are included in the governing equation of motion to compensate for the non-satisfied boundary conditions and increase the accuracy of the Galerkin method. The approximate numerical solution is accomplished using an iterative process due to the non-linearity of the unilateral property of the two-parameter foundation. The plate under static concentrated load is investigated in detail numerically by considering a wide range of parameters of the plate and the foundation stiffnesses. Numerical treatment of the problem in the time domain is carried out by assuming a stepwise variation of the concentrated load and the linear acceleration procedure is employed in the solution of the system of governing differential equations derived from the equation of motion. Time variations of the contact region and those of the displacements of the plate are presented in the figures for various numbers of the two-parameter of the foundation, as well as the classical and nano parameters of the plate particularly focusing on the non-linearity of the problem due to the plate lift-off from the unilateral foundation. The effects of classical and nonlocal parameters and loading are investigated in detail. Definition of the separation between the plate and the two-parameter foundation is presented and applied to the given problem. The effect of the lift-off on the static and dynamic behavior of the rectangular plate is studied in detail by considering various loading conditions. The numerical study shows that the effect of nonlocal parameters on the behavior of the plate becomes significant, when nonlinearity becomes more profound, due to the lift-off of the plate. It is seen that the size effects are significant in static and dynamic analysis of nano-scaled rectangular plates and need to be included in the mechanical analyses. Furthermore, the corner displacement of the plate is affected more significantly from the lift-off, whereas it is less marked in the time variation of the middle displacement of the plate. Several numerical examples are presented to examine the sensibility of various parameters associated with nonlocal parameters of the plate and foundation. Both stiffening and softening nonlocal parameters behavior of the plate are identified in the numerical solutions which show that increasing the foundation stiffness decreases the extent of the contact region, whereas the stiffness of the shear layer increases the contact region and reduces the foundation settlement considerably.

• Journal of Nutrition and Health
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• v.57 no.1
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• pp.88-104
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• 2024

Purpose: High-sensitivity C-reactive protein (hs-CRP) is primarily synthesized in the liver upon stimulation of infectious disease cytokines, such as interleukin-6 (IL-6), and is used as a biological marker of systemic inflammation. Previous studies reported that hs-CRP is closely related to diet and abdominal obesity. Furthermore, a dietary score favoring the consumption of vegetables, fruits, and whole grains over meat and saturated fat reduced inflammation and decreased the prevalence of obesity and abdominal obesity. Nevertheless, no studies have examined whether hs-CRP mediates the relationship between dietary scores and abdominal obesity, and research on the Korean Healthy Eating Index (KHEI) is lacking. Therefore, the present study examined the association between the KHEI and abdominal obesity and the mediating effect of hs-CRP. Methods: In total, 17,770 adults aged ≥19 years were included in the study using the Korea National Health and Nutrition Examination Survey 2015-2018. KHEI was developed to assess the overall diet quality of Korean adults. Multivariable linear and logistic regression analyses assessed the relationship between KHEI, hs-CRP, and abdominal obesity. The mediation analysis with the bootstrapping method was performed using SAS MACRO. Results: Among women, the odds ratio (OR) of abdominal obesity prevalence was lower in the highest KHEI compared to the lowest KHEI after adjusting for age, body mass index, educational level, income level, occupational status, marital status, household type, region type, alcohol consumption, smoking status, physical activity, total energy intake, and hsCRP (OR 0.744, 95% confidence interval 0.598-0.926). The association between KHEI and abdominal obesity was partially mediated via hs-CRP, and the mediated proportion was 68.7% in men and 38.1% in women. Conclusion: A substantial relationship was observed between the KHEI and abdominal obesity among females. Moreover, according to the KHEI, abdominal obesity may be mediated partially by hs-CRP.

• Sim-seong Yeon-gu
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• v.25 no.1
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• pp.1-26
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• 2010

The Ten Ox Herding Pictures by Kuo-an, a Zen Master of China in the Middle Ages are interpreted from the view point of the analytical psychology of C.G. Jung. Basically, I agree with the previous Jungian comments on it by M. J..Spiegelman, M.Miyuki, and H.Kawai at the Ox Herding Pictures are symbolic manifestations of the individuation process in terms of C.G.Jung. In connection with the process of Jungian analysis, I went through, not only the pictures but also the eulogies and critical comments of Zen masters in order to elucidate the symbolical meanings of each stage of spiritual development in Zen meditation. I noticed that the Ox Herding Pictures suggest the preference of suppression and conscious control of shadow in Jung's terms rather than its assimilation through making conscious the unconscious inferior personality. Also, the feminine psyche seems to be not particularly taken into consideration. In another words, different psychic aspects are represented in one single image : Ox. Due to the simplicity of pictorial expressions, the Ox Herding Pictures provide us possibilities to pour abundant imaginations into the pictures. The images comprise multiple irrational meanings; therefore it is warranted to render multiple interpretations of the Pictures as shown in the eulogies and comments by other Zen masters. The sequences of the Pictures need not coincide with a linear process but rather with a circular process of enlightenment, as Miyuki has suggested. Kuo-an's Pictures clearly suggest the danger of ego inflation and the fact that the final goal of Zen meditation should be the capability of the enlightened to serve the people.

• Journal of the Korean Society of Radiology
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• v.84 no.5
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• pp.1080-1090
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• 2023

Purpose This study aimed to compare the volume and normative percentiles of brain volumetry in the Korean population using quantitative brain volumetric MRI analysis tools NeuroQuant^Ⓡ (NQ) and DeepBrain^Ⓡ (DB), and to evaluate whether the differences in the normative percentiles of brain volumetry between the two tools is related to cranial shape. Materials and Methods In this retrospective study, we analyzed the brain volume reports obtained from NQ and DB in 163 participants without gross structural brain abnormalities. We measured threedimensional diameters to evaluate the cranial shape on T1-weighted images. Statistical analyses were performed using intra-class correlation coefficients and linear correlations. Results The mean normative percentiles of the thalamus (90.8 vs. 63.3 percentile), putamen (90.0 vs. 60.0 percentile), and parietal lobe (80.1 vs. 74.1 percentile) were larger in the NQ group than in the DB group, whereas that of the occipital lobe (18.4 vs. 68.5 percentile) was smaller in the NQ group than in the DB group. We found a significant correlation between the mean normative percentiles obtained from the NQ and cranial shape: the mean normative percentile of the occipital lobe increased with the anteroposterior diameter and decreased with the craniocaudal diameter. Conclusion The mean normative percentiles obtained from NQ and DB differed significantly for many brain regions, and these differences may be related to cranial shape.

• Dementia and Neurocognitive Disorders
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• v.21 no.1
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• pp.30-41
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• 2022

Background and Purpose: In this study we aimed to find the association between neuropsychological performance and body mass index (BMI) in patients with mild cognitive impairment (MCI). In addition, we investigated the effects of the apolipoprotein E (APOE) genotype in the relationship between the BMI and cognition in MCI. Methods: We enrolled a cohort of 3,038 subjects with MCI aged 65-90 from the Clinical Research Center for Dementia of South Korea and a dementia cohort of the Ewha Womans University Mokdong Hospital. MCI patients were classified into three subgroups according to the Asian standard of BMI. We compared cognitive performances between groups by one-way analysis of variance. To investigate the effects of the APOE genotype, we used multivariate linear regression models after adjusting for possible confounders. Results: Even though normal BMI groups were younger, had more females, and had less comorbidities, the higher BMI groups had better cognitive functions. Among subjects with APOE ε4 carriers, there was a positive relationship between the BMI and the memory task alone. Conclusions: Our findings suggested that higher BMI in patients with MCI were associated with better cognitive performance. The effects of the APOE ε4 genotype in the associations between BMI and cognition were distinguishing. Therefore, according to physical status, APOE ε4 genotype-specific strategies in the assessments and treatments may be necessary in elderly patients with MCI.

• Journal of Korea Port Economic Association
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• v.40 no.1
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• pp.133-149
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• 2024

According to previous studies, the key factor in determining the loan interest rate for shipping companies is the default risk premium. Therefore, this study analyzes the determinants of the risk premium of shipping loans using a multiple linear regression model. With the risk premium as the dependent variable, a total of 10 independent variables are selected, including three factors: loan characteristics, borrower's creditworthiness, and economic situation. Samples are 82 shipping loans supported by Bank A from 2014 to 2022. As a result, borrower's creditworthiness(current ratio, debt ratio, firm age) and economic situation(freight index) affect the risk premium in analysis for all samples. It is found that borrower's creditworthiness has some influence on the risk premium for container ships(current ratio, cash holding ratio, debt ratio, operating income to sales) and bulk carriers(debt ratio, firm age). Market situation affects the risk premium in gas carriers. However, in the model targeting tanker ships, unlike previous studies, all factors have no effect on the risk premium.

• International Journal of Stem Cells
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• v.15 no.4
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• pp.395-404
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• 2022

Background and Objectives: Chronic obstructive pulmonary disease (COPD) is a common, frequently-occurring disease and poses a major health concern. Unfortunately, there is current no effective treatment for COPD, particularly emphysema. Recently, experimental treatment of COPD using mesenchymal stem cells (MSCs) mainly focused on bone marrow-derived MSCs (BM-MSCs). Human umbilical cord-derived MSCs (hUC-MSCs) have more advantages compared to BM-MSCs. However, studies on the role of hUC-MSCs in management of COPD are limited. This study sought to explore the role of hUC-MSCs and its action mechanisms in a rat model of VEGF receptor blocker SU5416-injured emphysema. Methods and Results: hUC-MSCs were characterized by immunophenotype and differentiation analysis. Rats were divided into four groups: Control, Control+MSC, SU5416 and SU5416+MSC. Rats in model group were administered with SU5416 for three weeks. At the end of the second week after SU5416 administration, model group were infused with 3×10⁶ hUC-MSCs through tail vein. After 14 days from hUC-MSCs transplantation, rats were euthanized and data were analyzed. HE staining and mean linear intercepts showed that SU5416-treated rats exhibited typical emphysema while emphysematous changes in model rats after hUC-MSCs transplantation disappeared completely and were restored to normal phenotype. Furthermore, hUC-MSCs inhibited apoptosis as shown by TUNEL and Western blotting. ELISA and Western blotting showed hUC-MSCs rescued VEGF-VEGFR2-AKT pathway in emphysematous lungs. Conclusions: The findings show that hUC-MSCs effectively repair the emphysema injury. This study provides the first evidence that hUC-MSCs inhibit apoptosis via rescuing VEGF- VEGFR2-AKT pathway in a rat model of emphysema.

• Journal of the Korean Physical Society
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• v.80
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• pp.516-525
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• 2022

This study is to assess the clinical use of commercial PerFRACTION^TM for patient-specific quality assurance of volumetric-modulated arc therapy. Forty-six pretreatment verification plans for patients treated using a TrueBeam STx linear accelerator for lesions in various treatment sites such as brain, head and neck (H&N), prostate, and lung were included in this study. All pretreatment verification plans were generated using the Eclipse treatment planning system (TPS). Dose distributions obtained from electronic portal imaging device (EPID), ArcCHECK^TM, and two-dimensional (2D)/three-dimensional (3D) PerFRACTION^TM were then compared with the dose distribution calculated from the Eclipse TPS. In addition, the correlation between the plan complexity (the modulation complexity score and the leaf travel modulation complexity score) and the gamma passing rates (GPRs) of each quality assurance (QA) system was evaluated by calculating Spearman's rank correlation coefficient (r_s) with the corresponding p-values. The gamma passing rates of 46 patients analyzed with the 2D/3D PerFRACTION^TM using the 2%/2 mm and 3%/3 mm criteria showed almost similar trends to those analyzed with the Portal dose imaging prediction (PDIP) and ArcCHECK^TM except for those analyzed with ArcCHECK^TM using the 2%/2 mm criterion. Most of weak or moderate correlations between GPRs and plan complexity were observed for all QA systems. The trend of mean rs between GPRs using PDIP and 2D/3D PerFRACTION^TM for both criteria and plan complexity indices as in the GPRs analysis was significantly similar for brain, prostate, and lung cases with lower complexity compared to H&N case. Furthermore, the trend of mean rs for 2D/3D PerFRACTION^TM for H&N case with high complexity was similar to that of ArcCHECK^TM and slightly lower correlation was observed than that of PDIP. This work showed that the performance of 2D/3D PerFRACTION^TM for pretreatment patient-specific QA was almost comparable to that of PDIP, although there was small difference from ArcCHECK^TM for some cases. Thus, we found that the PerFRACTION^TM is a suitable QA system for pretreatment patient-specific QA in a variety of treatment sites.

• Journal of Bio-Environment Control
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• v.33 no.1
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• pp.1-11
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• 2024

In this study, five artificial intelligence (AI) models: Inception v3, SqueezeNet (local), VGG-16, Painters, and DeepLoc were used to classify tea leaf diseases. Eight image categories were used: healthy, algal leaf spot, anthracnose, bird's eye spot, brown blight, gray blight, red leaf spot, and white spot. Software used in this study was Orange 3 which functions as a Python library for visual programming, that operates through an interface that generates workflows to visually manipulate and analyze the data. The precision of each AI model was recorded to select the ideal AI model. All models were trained using the Adam solver, rectified linear unit activation function, 100 neurons in the hidden layers, 200 maximum number of iterations in the neural network, and 0.0001 regularizations. To extend the functionality of Orange 3, new add-ons can be installed and, this study image analytics add-on was newly added which is required for image analysis. For the training model, the import image, image embedding, neural network, test and score, and confusion matrix widgets were used, whereas the import images, image embedding, predictions, and image viewer widgets were used for the prediction. Precisions of the neural networks of the five AI models (Inception v3, SqueezeNet (local), VGG-16, Painters, and DeepLoc) were 0.807, 0.901, 0.780, 0.800, and 0.771, respectively. Finally, the SqueezeNet (local) model was selected as the optimal AI model for the detection of tea diseases using tea leaf images owing to its high precision and good performance throughout the confusion matrix.

• Korean Journal of Environment and Ecology
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• v.38 no.4
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• pp.426-433
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• 2024

In this study, to estimate the effects of plant-induced surface area increase and physiological activity on fine dust purification, a control group was set up. We utilized both foliage plants (Spathiphyllum wallisii) and artificial plants (shaped like Spathiphyllum wallisii) to measure and compare the purification time for fine dust. The results showed that the time required for fine dust purification in each experimental group decreased by 57-64% for Type AP and 31-32% for Type P compared to the control group. Subsequently, using a Linear Mixed Model (LMM), we tested the interaction between time and each experimental group, revealing statistically significant interactions between surface area increase and time(PM10 : t=3.123, p<0.05, PM2.5 : t=3.180, p<0.05), as well as physiological activity and time(PM10 : t=4.065, p<0.05, PM2.5 : t=4.307, p<0.05), indicating the presence of interactions between each factor and the time variable. Finally, we estimated the efficiency of fine dust purification by plant factors through nonlinear regression analysis. Compared to the control group without purification factors (Type C), it was estimated that surface area increase shortened the purification time by 1.40 times and physiological activity by an average of 1.95 times, resulting in a total 2.74 times shorter purification time. Based on these results, we hypothesized that physiological activity(transpiration and absorption) has a greater impact on fine dust purification than surface area increase(biosorption). Accordingly, we emphasize the importance of vegetation management practices such as pruning and irrigation management in green spaces aimed at fine dust purification.