• Bulletin of the Society of Naval Architects of Korea
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• v.19 no.1
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• pp.3-14
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• 1982

In this paper, the sway added mass of a rectangular cylinder in a restricted water is considered by applying Hamilton's principle as the frequency tends to zero. The present method is an extension of Isshiki's method proposed in 1978. In the present method, it is assumed that the fluid velocity distribution in each subdomain of the fluid can be represented by higher order polynomials while Isshiki assumed linear velocity distribution. The fluid flow is assumed as a rotational motion in the present analysis. However, the results obtained from the present method show good agreement with Bai's numerical results for the case of large clearances between a canal wall and a cylinder. From Kelvin's minimum energy theorem, we can see that the value of sway added mass obtained from the present method approaches the upper bound. The approximate formula obtained in the present study takes a simple form which consists of the dimensions of the canal and the cylinder. The present formulae are derived for the cases of a rectangular cylinder swaying at the center of a narrow or wide canal relative to a cylinder, at off-center location in a canal, and in the restricted water with a single wall. From the results of numerical calculation, it is concluded that the sway added mass in restricted waters is more affected by water depth than clearance between a wall and a cylinder.

• Women's Health Nursing
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• v.29 no.3
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• pp.190-199
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• 2023

Purpose: This study aimed to describe the characteristics of mobile applications (apps) related to pregnancy in South Korea and evaluate their quality. Methods: We conducted a systematic search for pregnancy-related apps available in Korea in two app stores as of April 29, 2022. The quality of apps was assessed using the Korean translation of the Mobile Application Rating Scale for objective quality with four subdomains (engagement, function, aesthetics, and information) and four items for subjective quality. Results: In total, 163 apps were selected and reviewed. Both the objective and subjective quality of the apps were found to be desirable, with scores exceeding 3 out of 5 (range, 34-82). All subdomain scores in the objective quality assessment were also desirable. Among the four objective quality subdomains, aesthetics received the highest scores, followed by information, function, and engagement. In terms of subjective quality, the scores for a comprehensive overall evaluation, continuous use, and recommendation exceeded 3 out of 5, with the exception of payment. Only a small number of apps (n=4, 2.9%) were backed by a reliable authority, such as an expert review. Significant differences were observed in the objective quality of apps across different content categories (F=3.86, p=.003). Conclusion: Most pregnancy-related apps had desirable levels of objective and subjective quality. However, app content experts seldom provide reviews. It is crucial for nurses to recommend apps to expectant mothers that offer dependable content, regularly updated with the latest information.

• 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 Computational Structural Engineering Institute of Korea
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• v.31 no.3
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• pp.155-163
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• 2018

One of the major disadvantages of isogeometric analysis(IGA) is that local refinement is nearly impossible in a conventional manner because of the tensor product nature in NURBS. In this research, we investigate a local refinement scheme for isogeometric analysis, named multi-resolution approach where different resolutions are employed at each subdomain, using h-refinement relation to endow displacement compatibility on an interface of subdomains. Then, we develop shape sensitivity analysis possessing same compatibility condition as in the analysis. Numerical examples are shown to demonstrate the computational efficiency of the method in analysis especially stress concentration problem and accurate sensitivity results which is also compatible on the interface.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.22 no.3
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• pp.192-197
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• 2011

Objectives: This study was conducted to examine the prevalence and characteristics of savant skills and the relationship between the savant skills and autistic symptoms in Korean ASD children. Methods: 141 ASD subjects participated in this study and they were divided in to two groups based on the presence or lack of savant skills. The domain scores and total scores of the K-ADI-R, K-ASDS and SRS were used for evaluating the ASD symptoms between the groups. Results: Memory (N=47) was the most prevalent savant skill in the savant ASD group (N=60). The savant ASD group had a statistically higher mean age and IQ score than did the nonsavant ASD group. Despite their high IQ profile, the savant ASD group showed a higher restricted, repetitive and stereotype behavior score on the K-ADI-R and higher language and cognitive scores on the K-ASDS than did the nonsavant ASD group. Conclusions: These results suggest savant syndrome in ASD might be related to the severity of some subdomain of autistic symptoms even though their IQ scores were higher than nonsavant ASD patients.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.23 no.5
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• pp.475-482
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• 2010

In this paper, an efficient two-level parallel domain decomposition algorithm is suggested to solve large-DOF structural problems. Each subdomain is composed of the coarse problem and local problem. In the coarse problem, displacements at coarse nodes are computed by the iterative method that does not need to assemble a stiffness matrix for the whole coarse problem. Then displacements at local nodes are computed by Multi-Frontal Sparse Solver. A parallel version of PCG(Preconditioned Conjugate Gradient Method) is developed to solve the coarse problem iteratively, which minimizes the data communication amount between processors to increase the possible problem DOF size while maintaining the computational efficiency. The test results show that the suggested algorithm provides scalability on computing performance and an efficient approach to solve large-DOF structural problems.

• Bulletin of the Korean Mathematical Society
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• v.55 no.3
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• pp.957-965
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• 2018

We study the class $C{\mathcal{V}} ({\Omega})$ of analytic functions f in the unit disk ${\mathbb{D}}=\{z{\in}{\mathbb{C}}$ : ${\mid}z{\mid}$ < 1} of the form $f(z)=z+{\sum}_{n=2}^{\infty}a_nz^n$ satisfying $$1+\frac{zf^{{\prime}{\prime}}(z)}{f^{\prime}(z)}{\in}{\Omega},\;z{\in}{\mathbb{D}}$$, where ${\Omega}$ is a convex and proper subdomain of $\mathbb{C}$ with $1{\in}{\Omega}$. Let ${\phi}_{\Omega}$ be the unique conformal mapping of $\mathbb{D}$ onto ${\Omega}$ with ${\phi}_{\Omega}(0)=1$ and ${\phi}^{\prime}_{\Omega}(0)$ > 0 and $$k_{\Omega}(z)={\displaystyle\smashmargin{2}{\int\nolimits_{0}}^z}{\exp}\({\displaystyle\smashmargin{2}{\int\nolimits_{0}}^t}{\zeta}^{-1}({\phi}_{\Omega}({\zeta})-1)d{\zeta}\)dt$$. Let $z_0,z_1{\in}{\mathbb{D}}$ with $z_0{\neq}z_1$. As the first result in this paper we show that the region of variability $\{{\log}\;f^{\prime}(z_1)-{\log}\;f^{\prime}(z_0)\;:\;f{\in}C{\mathcal{V}}({\Omega})\}$ coincides wth the set $\{{\log}\;k^{\prime}_{\Omega}(z_1z)-{\log}\;k^{\prime}_{\Omega}(z_0z)\;:\;{\mid}z{\mid}{\leq}1\}$. The second result deals with the case when ${\Omega}$ is the right half plane ${\mathbb{H}}=\{{\omega}{\in}{\mathbb{C}}$ : Re ${\omega}$ > 0}. In this case $CV({\Omega})$ is identical with the usual normalized class of convex univalent functions on $\mathbb{D}$. And we derive the sharp upper bound for ${\mid}{\log}\;f^{\prime}(z_1)-{\log}\;f^{\prime}(z_0){\mid}$, $f{\in}C{\mathcal{V}}(\mathbb{H})$. The third result concerns how far two functions in $C{\mathcal{V}}({\Omega})$ are from each other. Furthermore we determine all extremal functions explicitly.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1997.04a
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• pp.86-86
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• 1997

Human annexin I is a member of annexin family of calcium dependent phospholipid binding proteins, which have been implicated in various physiological roles including phospholipase A$_2$ (PLA$_2$) inhibition, membrane fusion and calcium channel activity. In this work, the structure of N-terminally truncated human annexin I (Δ-annexin I) and its interactions with Ca$\^$2+/, ATP and cAMP were studied at atomic level by using $^1$H, $\^$15/N, $\^$l3/C NMR (nuclear magnetic resonance) spectroscopy. The effect of Ca$\^$2+/ binding on the structure of Δ-annexin I was investigated, and compared with that of Mg$\^$2+/ binding. The addition of Ca$\^$2+/ to Δ-annexin I caused some changes in the high field and low field regions of $^1$H NMR spectra. Whereas, upon addition of Mg$\^$2+/ to Δ-annexin I, almost no change could be observed. Also we found that the binding ratio of ATP to Δ-annexin I is 1. Because Δ-annexin I is a large protein with 35 kDa molecular weight, site-specific (carbonyl-$\^$l3/C, amide-$\^$15/N) labeling technique was used to determine the interaction sites of Δ-annexin I with Ca$\^$2+/ and ATP. Assignments of all the histidinyl carbonyl carbon resonances have been completed by using Δ-annexin I along with its specific 1,2-subdomain. The carbonyl carbon resonances originating from His52 and His246 of Δ-annexin I were significantly affected by Ca$\^$2+/ binding, and some Tyr and Phe resonances were also affected. The carbonyl carbon resonances originating from His52 is significantly affected by ATP binding, therefore His52 seems to be involved in the ATP binding site of Δ-annexin I.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.12
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• pp.7160-7169
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• 2014

This study examined the relationship of academic failure tolerance, academic self-efficacy and academic achievement of nursing students. The data was obtained from August 27 to September 17. The participants were 198 students in a university in D city. The data was analyzed using descriptive statistics, Pearson correlation coefficients and multiple regression. A positive correlation was observed between all the variables. The factor that significantly affected academic achievement was academic self-efficacy, which explained 7.5% of the variances. The subdomain of the academic failure tolerance affecting academic achievement was found to be the behavior, which explained 8.0% of variances. The subdomains of academic self-efficacy affecting the academic achievement was the self-regulatory efficacy. This factor explained 15.4% of the variances. This study suggests that it is necessary to enhance the academic failure tolerance and academic self-efficacy for the learning achievement and working performance of nursing students.

• International Journal of Contents
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• v.11 no.4
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• pp.31-37
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• 2015

The objectives of this study were: 1) to determine smartphone addiction, visual display terminal syndrome (VDTS) related symptoms, and state anxiety among adolescents, and 2) to identify the relationship among these variables. Data were collected via selfadministrated questionnaire survey from May to June, 2013. The survey was carried out with 540 voluntary participants at 13 to 24 years old from middle schools, high schools, and universities in Korea. The presence and severity of smartphone addiction, VDTS symptoms, and state anxiety were measured using Korean Smartphone Addiction Proneness Scale, VDTS Questionnaire, and State Anxiety Inventory, respectively. Data were analyzed by Cohen’s Kappa coefficient, Kruskal-Wallis test, and Mann-Whitney U test. The mean score of smartphone addiction for all students was 2.17 ± 0.51. The mean scores of smartphone addiction depending on school grade were 2.12 ± 0.53, 2.03 ± 0.48, and 2.42 ± 0.43 for middle school, high school, and college students, respectively. Subjects who experienced minor level of VDTS symptoms had a score of 0.49 ± 0.49 for VDTS symptoms. The score was increased when the level of addiction was higher. There were significant differences in VDTS subjective symptoms among smartphone addiction groups (p<.001). High-risk group of smartphone addiction had the highest scores in every subdomain of VDTS symptoms. Differences were also found in state anxiety among the three groups with smartphone addiction. The findings of this study showed that approximately one out of three adolescents might be classified into problematic smartphone users. Therefore, it is important to educate problematic smartphone users about smartphone addiction and VDTS symptoms to prevent further addiction and aggravation of anxiety.