• Journal of the Korean Magnetics Society
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• v.18 no.5
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• pp.180-184
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• 2008

The relation of ferromagnet anisotropic magnetization and the antiferromagnet atomic spin configuration has been investigated for variously angles of unidirectional deposition magnetic field of FeMn layer in Corning glas/Ta(5 nm)/NiFe(7 nm)/FeMn(25 nm)/ Ta(5 nm) multilayer prepared by ion beam deposition. Three unidirectional deposition angles of FeMn layer are $0^{\circ},\;45^{\circ}$, and $90^{\circ}$, respectively. The exchange bias field ($H_{ex}$) obtained from the measuring easy axis MR loop was decreased to 40 Oe in deposition angle of $45^{\circ}$, and to 0 Oe in the angle of $90^{\circ}$. One other side hand, $H_{ex}$ obtained from the measuring hard axis MR loop was increased to 35 Oe in deposition angle of $45^{\circ}$, and to 79 Oe in the angle of $90^{\circ}$. Although the difference of uniderectional axis between ferromagnet NiFe and antiferromagnet FeMn was 90o, the strong antiferromagnetic dipole moment of FeMn caused to rotate the weak ferromagnetic dipole moment of NiFe in the interface. This result implies that one of origins for exchange coupling mechanism depends on the effect of magnetic field angle during deposition of antiferromgnet FeMn layer.

• Journal of Korea Port Economic Association
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• v.31 no.1
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• pp.1-14
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• 2015

The standard GARCH model imposing symmetry on the conditional variance, tends to fail in capturing some important features of the data. This paper, hence, introduces the models capturing asymmetric effect. They are the EGARCH model and the GJR model. We provide the systematic comparison of volatility models focusing on the asymmetric effect of news on volatility. Specifically, three diagnostic tests are provided: the sign bias test, the negative size bias test, and the positive size bias test. This paper shows that there is significant evidence of GARCH-type process in the data, as shown by the test for the Ljung-Box Q statistic on the squared residual data. The estimated unconditional density function for squared residual is clearly skewed to the left and markedly leptokurtic when compared with the standard normal distribution. The observation of volatility clustering is also clearly reinforced by the plot of the squared value of residuals of export volume and values. The unconditional variance of both export volumes and export value indicates that large shocks of either sign tend to be followed by large shocks, and small shocks of either sign tend to follow small shocks. The estimated export volume news impact curve for the GARCH also suggests that $h_t$ is overestimated for large negative and positive shocks. The conditional variance equation of the GARCH model for export volumes contains two parameters ${\alpha}$ and ${\beta}$ that are insignificant, indicating that the GARCH model is a poor characterization of the conditional variance of export volumes. The conditional variance equation of the EGARCH model for export value, however, shows a positive sign of parameter ${\delta}$, which is contrary to our expectation, while the GJR model exhibits that parameters ${\alpha}$ and ${\beta}$ are insignificant, and ${\delta}$ is marginally significant. That indicates that the asymmetric volatility models are poor characterization of the conditional variance of export value. It is concluded that the asymmetric EGARCH and GJR model are appropriate in explaining the volatility of export volume, while the symmetric standard GARCH model is good for capturing the volatility.

• Journal of Obesity & Metabolic Syndrome
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• v.25 no.3
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• pp.138-148
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• 2016

Background: The purpose of this study is to analyze the effects of an abdominal obesity management program in middle-aged women in Korea. Methods: Examination of databases, including the Research Information Sharing Service, Database Periodical Information Academic, and Korean Studies Information, resulted in identification of 772 studies performed up to 2014, of which 43 satisfied the inclusion data. Data analysis was performed using R version 3.2 to calculate the effect sizes, explore possible causes of heterogeneity, and check for publication bias, using a funnel plot and its trim-and-fill analysis. Results: The mean effect size of the management program was small (g=0.22), along with the anthropometric index (g=0.18), metabolism index (g=0.21), fat-distribution (g=0.36), and inflammatory index (g=0.36). Moderator analysis was performed to determine heterogeneity, but no significant differences were found between the randomized controlled trial (RCT) group and non-RCT group. In addition, the length of the session was found to be statistically significant after performing a meta-regression. Finally, a funnel plot with a trim-and-fill analysis was produced to check for publication bias, but no significant bias was detected. Conclusion: Based on these findings, the abdominal obesity management program affects middle-aged women in Korea. Further research is needed to target other age groups with abdominal obesity.

• Korean Journal of Culture and Social Issue
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• v.23 no.2
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• pp.271-293
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• 2017

Despite the benefits of social activity on happiness, humans still spend over one third of their time by themselves-sleeping. The effect of sleep quality on happiness as well as its underlying mechanism are examined in this study. Based on previous findings on the role of sleep in consolidation of memories, it was hypothesized that a good sleep would promote happiness by increasing the likelihood of recalling everyday episodes in a positively biased manner. In Study 1, regardless of one's demographic variables, social variables, and economic status, sleep quality was positively related to life satisfaction. To examine the causal direction of this effect, participants were asked to complete a survey twice with different time intervals. Controlling for baseline variables, sleep quality during previous two weeks (Study 2) or previous day (Study 3) significantly predicted the participants' life satisfaction. Moreover, this relationship was partially mediated by a positive memory bias (Study 3). This study opens interesting questions on a relatively unexamined nonsocial predictor of happiness, sleep quality.

• Journal of Electrical Engineering and Technology
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• v.2 no.2
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• pp.267-273
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• 2007

A depletion-mode MOSFET has been analyzed to evaluate its electrical behavior using a novel 3-D numerical simulation package. The characterizing analysis of the BC MOSFET was performed through short-channel narrow-channel and small-geometry effects that are investigated, in detail, in terms of the threshold voltage. The DIBL effect becomes significant for a short-channel device with a channel length of $<\;3({\mu}m)$. For narrow-channel devices the variation of the threshold voltage was sharp for $<4({\mu}m)$ due to the strong narrow-channel effect. In the case of small-geometry devices, the shift of the threshold voltage was less sensitive due to the combination of the DIBL and substrate bias effects, as compared with that observed from the short-channel and narrow-channel devices. The characterizing analysis of the narrow-channel and small-geometry devices, especially with channel width of $<\;4({\mu}m)$ and channel area of $<\;4{\times}4({\mu}m^2)$ respectively, can be accurately performed only from a 3-D numerical simulation due to their sharp variations in threshold voltages.

• The Journal of Korean Academic Society of Nursing Education
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• v.27 no.1
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• pp.5-15
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• 2021

Purpose: This study aimed to provide a systematic review and meta-analysis of research on flipped learning effects applied to university students. Methods: The random effect model was applied to 21 papers to calculate the effect size. To verify the moderation effect, a meta regression analysis and meta ANOVA were performed. Publication bias was verified through a funnel plot, and then an Egger's regression test was conducted. Results: The overall average effect size was .69 (95% CI: .51-.87), showing a median effect size, which was statistically significant. The outcome variables were in the order of learning motivation (Hedges' g=.83), self-directed learning (Hedges' g=.78), learning achievement (Hedges' g=.66), and efficacy (Hedges' g=.50), which were statistically significant. Conclusion: Flipped learning was found to be statistically significant in improving self-directed learning, learning motivation, efficacy, and learning achievement amng university students. It is suggestd that this method be actively applied in university education.

• Child Health Nursing Research
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• v.28 no.1
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• pp.23-40
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• 2022

Purpose: This systematic review and meta-analysis investigated the effects of parenting education programs (PEPs) for refugee and migrant parents. Methods: A systematic review was conducted according to PRISMA guidelines. Relevant studies published from 2000 to 2020 were identified through a systematic search of six electronic databases (PubMed, Embase, Cochrane Library, CINAHL, RISS, KMBASE). A meta-analysis of the studies was then undertaken. Results: Of the 14,996 published works identified, 23 studies satisfied the inclusion criteria, and 19 studies were analyzed to estimate the effect sizes (standardized mean differences) of the PEPs using random-effect models. PEPs were effective for parenting efficacy (effect size [ES]=1.40; 95% confidence interval [CI]: 1.14-1.66), positive parenting behaviors (ES=0.51; 95% CI: 0.30-0.73), parent-child relationships (ES=0.38; 95% CI: 0.22-0.53), and parenting stress (ES=0.64; 95% CI: 0.50-0.79). There were statistically significant differences in the effect sizes of PEPs that included mothers only (ES=0.93), included children under 7 years of age(ES=0.91), did not include child participation (0.77), continued for 19 or more sessions (ES=0.80), and were analyzed in quasi-experimental studies (ES=0.86). The overall effect of publication bias was robust. Conclusion: PEPs were found to be effective at improving parenting efficacy, positive parenting behaviors, parent-child relationships, and parenting stress.

• Physical Therapy Rehabilitation Science
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• v.12 no.1
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• pp.48-55
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• 2023

Objective: The purpose of this study is to compare the effects of extracorporeal shock wave therapy (ESWT) and injection therapy through qualitative and quantitative analysis by synthesizing randomized controlled trials (RCTs) conducted on patients with various shoulder diseases. Design: A systematic review and meta-analysis of randomized controlled trials Methods: This review conducted a literature search through international electronic databases in January 2023 to compare the effects of ESWT and injection therapy. Qualitative analysis was performed as a risk of bias tool, and quantitative analysis was synthesized with a random effect model to show the effect size as a standardized mean difference (SMD). Results: Five RCTs involving 298 individuals with shoulder disorders were included in this systematic review and meta-analysis. ESWT showed a moderate effect on pain (SMD=-0.44; 95% CI, -0.95 to 0.06) and a large effect on shoulder function (SMD =-0.81; 95% CI, -1.70 to 0.07) than injection therapy. A significant difference was found in the shoulder range of motion, showing a large effect size (SMD=1.50; 95% CI, 0.58 to 2.43). Conclusions: When considering treatment options for the management of patients complaining of shoulder disorders, it is appropriate to recommend ESWT first rather than injection therapy to increase the range of motion of the joint. In addition, ESWT is safe for pain control and shoulder function improvement, and a positive prognosis could be expected.

• Physical Therapy Rehabilitation Science
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• v.12 no.1
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• pp.12-18
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• 2023

Objective: Chemotherapy is usually given to inhibit cancer progression. It is the most common side effect of chemotherapyinduced peripheral neuropathy (CIPN) after chemotherapy, and its symptoms include pain such as paresthesia, dysesthesia, allodynia, hyperalgesia, and electrical stimulation. Therefore, in this review, randomized controlled trials (RCTs) were combined to analyze the effect qualitatively and quantitatively in order to find out the effect of manual therapy on patients with CIPN through a meta-analysis. Design: A systematic review and meta-analysis Methods: This review conducted a literature search through international databases (CINAHL, Embase, MEDLINE, Web of Science) in December 2022 to synthesize the effect of manual therapy on the symptomatic improvement of CIPN. Qualitative evaluation (risk of bias) and quantitative evaluation using ReVMan provided by the Cochrane Group were expressed as a random effect model and standardized mean difference (SMD). Results: In four RCTs 165 patients with CIPN were evaluated for symptoms of neuropathy. The experimental group consisting of manual therapy and its subcategories showed significant improvement compared to the control group. The results analyzed through the random effects model were SMD=-1.11; 95% confidence interval, -1.97 to -0.24. Conclusions: We came to the conclusion that manual therapy could significantly contribute to improving the symptoms of CIPN, and since it may vary depending on the technique of manual therapy, further studies on manual therapy suitable for neuropathy are needed.

• Proceedings of the IEEK Conference
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• 2004.08c
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• pp.460-462
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• 2004

The control of the data retention time is a main issue for realizing future high density dynamic random access memory. There are several leakage current mechanisms in which the stored data disappears. The mechanisms of data disappear is as follow, 1 )Junction leakage current between the junction, 2) Junction leakage current from the capacitor node contact, 3)Sub-threshold leakage current if the transfer transistor is affected by gate etch damage etc. In this paper we showed the plasma edge damage effect to find out data retention time effectiveness. First we measured the transistor characteristics of forward and reverse bias. And junction leakage characteristics are measured with/without plasma damage by HP4145. Finally, we showed the comparison TRET with etch damage, damage_cure_RTP and hydrogen_treatment. As a result, hydrogen_treatment is superior than any other method in a curing plasma etch damage side.