• East Asian mathematical journal
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• v.34 no.5
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• pp.571-575
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• 2018

Let D be an integral domain, ${\ast}$ a star-operation on D, and S a (not necessarily saturated) multiplicative subset of D. In this article, we prove the Cohen type theorem for $S-{\ast}_{\omega}$-principal ideal domains, which states that D is an $S-{\ast}_{\omega}$-principal ideal domain if and only if every nonzero prime ideal of D (disjoint from S) is $S-{\ast}_{\omega}$-principal.

• Journal of Integrative Natural Science
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• v.7 no.4
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• pp.278-282
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• 2014

We define a numerical invariant $row^*_j(A)$ over Cohen-Macaulay local ring A, which is related to the presenting matrices of the j-th syzygy module (with or without free summands). We show that $row_d(A)$=$row_{CM}(A)$ and $row^*_d(A)$=$row^*_{CM}(A)$ for a Cohen-Macaulay local ring A of dimension d.

• Bulletin of the Korean Mathematical Society
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• v.54 no.4
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• pp.1323-1330
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• 2017

For a nondegenerate projective irreducible variety $X{\subset}{\mathbb{P}}^r$, it is a natural problem to find an upper bound for the value of $${\ell}_{\beta}(X)=max\{length(X{\cap}L){\mid}L={\mathbb{P}}^{\beta}{\subset}{\mathbb{P}}^r,\;{\dim}(X{\cap}L)=0\}$$ for each $1{\leq}{\beta}{\leq}e$. When X is locally Cohen-Macaulay, A. Noma in [10] proves that ${\ell}_{\beta}(X)$ is at most $d-e+{\beta}$ where d and e are respectively the degree and the codimension of X. In this paper, we construct some surfaces $S{\subset}{\mathbb{P}}^5$ of degree $d{\in}\{7,{\ldots},12\}$ which satisfies the inequality $${\ell}_2(S){\geq}d-3+{\lfloor}{\frac{d}{2}}{\rfloor}$$. This shows that Noma's bound is no more valid for locally non-Cohen-Macaulay varieties.

• The Korean Journal of Pain
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• v.36 no.2
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• pp.195-207
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• 2023

Background: This study aimed to compare the effectiveness of the pericapsular nerve group (PENG) block and intra-articular injection (IAI) of steroid-bupivacaine in the treatment of hip osteoarthritis (OA). Methods: After randomization, patients received either a PENG block or IAI under ultrasound-guidance. Clinical evaluations were recorded at baseline, day 1, and weeks 1, 4, and 8 post-intervention. The numerical rating scale (NRS), Western Ontario and McMaster Universities Arthritis Index (WOMAC), Harris Hip Scale (HHS) scores, pain medication use determined by a quantitative analgesic questionnaire, and patient satisfaction were evaluated. Results: Sixty patients were included in this study. NRS scores improved significantly for both groups during the follow-up compared to pretreatment (P < 0.001), with better pain scores for the PENG group (P < 0.001) at day 1 with larger effect size (Cohen's d = 4.62), and IAI group at 4 (Cohen's d = 5.15) and 8 (Cohen's d = 4.33) weeks (P < 0.001). There was no significant difference in pain medication consumption (P = 0.499) and patient satisfaction (P = 0.138) between groups. Patients in the IAI group experienced significant improvement in HHS (Cohen's d = 2.16, P = 0.007) and WOMAC (Cohen's d = 1.02, P = 0.036) scores at 8 weeks compared to the PENG group. Conclusions: The ultrasound-guided PENG block provides effective pain relief which improves functionality and quality of life in hip OA patients up to 2 months. The PENG block can be considered an easy, safe, and useful alternative treatment modality for hip OA.

• Journal of Korean Physical Therapy Science
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• v.29 no.2
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• pp.57-65
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• 2022

Background: This study was to determine whether the diaphragmatic breathing exercise using a DiP Belt(Diaphragmatic Pressure Belt) is effective in increasing the diaphragmatic motion and forced vital capacity. Design: Pretest-Posttest design. Methods: A total of 44 subjects(15 male, 29 female) participated in this study. All subjects were measured the diaphragmatic motion with a sonography and the Forced Vital Capacity(FVC) was measured with a digital spirometer. After 4 weeks, the subjects were intervened the diaphragmatic breathing exercise using a DiP belt and were remeasured for diaphragm motion and FVC. Results: After exercise intervention, quiet breathing significantly increased with the change in diaphragmatic motion and showed a moderate effect size (p<.01, Cohen's d = -0.53). In addition, it was significantly increased in deep breathing and showed a high effect size (p<.001, Cohen's d = -1.32). The mean diaphragmatic contraction pressure increased, but there was no significant difference and the peak diaphragmatic contraction pressure increased significantly (p<.05). Both diaphragmatic contraction pressure showed small effect sizes (respectively Cohen's d = -0.28, -0.33). In spirometry, FVC, Forced Expiratory Volume in 1 second (FEV₁), and FEV₁/FVC% all increased, but there was no significant difference. Only peak expiratory flow increased significantly and showed a small effect size (p<.05, Cohen's d = -0.41). Conclusion: The DiP belt diaphragmatic breathing exercise that the principle of visual feedback can correct diaphragm breathing in a short time, so it is a useful breathing exercise device that can help the diaphragm breathing exercise in the right way in clinical practice.

• Journal of Korean Elementary Science Education
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• v.41 no.1
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• pp.65-78
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• 2022

This study aims to 1) verify the validity of the Science self-efficacy scale and 2) perform a latent mean analysis of the background variables about a pre-service teacher. The study uses pre-tests to analyze data from 187 pre-service teachers, which uses Tark's Science self-efficacy scale (2011). To identify the factor structure, exploratory factor analysis was performed. Based on the results of the pilot test, the expert group council revised the scale for the pre-service teachers to respond to the 3-factor structure. In the main test, 354 data were analyzed through a modified Science self-efficacy scale, and exploratory and confirmatory factor analyses were performed. The results of the study are as follows: First, in the pilot test, the pre-service teacher responded to a 3-factor instrument, but the validity of two items was examined further below. Second, the pre-service teachers responded to a 3-factor instrument on 29 items for the modified Science self-efficacy scale. The total reliability of the instrument was .886 and the reliability of each factor was analyzed as .882-.886. Finally, the latent mean analysis by gender showed that females have a higher self-regulation efficacy factor and males have a higher self-confidence factor (Cohen's d > .3). Furthermore, there is a significant difference in task difficulty preference and self-regulatory efficacy factor (Cohen's d > .8) between the college preparatory and science subject preference. This study provides important insights into and contributions to the accurate scientific self-efficacy diagnosis of pre-service teachers, as well as proposes a curriculum to improve the scientific self-efficacy of prospective teachers.

• The Journal of Korean Institute for Practical Engineering Education
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• v.2 no.1
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• pp.52-57
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• 2010

Using the Operating Systems course that is offered by online, a blended learning mixed up with face-to-face lecture and e-learning for O.S. course has been carried out. In order to find a efficient management way of the blended learning, we build up two groups: one group named 01 takes a class which consists of two hours face-to-face lecture and one hour online study per week and the other group named 02 takes a class which consists of two hours online study and one hour face-to-face lecture. According to the result of a mid-term examination, the Cohen's d between two groups is 0.165. It means the small effect size. The 01 group has higer average and smaller variance than 02 group. However, 02 group has more students who earn high score than 01 group. In conclusion, if students can well carry out the self-regulated learning, then the blended learning mixed up with 02 group style is suitable. Otherwise, face-to-face lecture or the blended learning like 01 group style is suitable.

• The Korean Journal of Pain
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• v.35 no.2
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• pp.191-201
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• 2022

Background: This study aimed to assess the efficacy of the adductor canal block (ACB) in comparison to intra-articular steroid-lidocaine injection (IASLI) to control chronic knee osteoarthritis (KOA) pain. Methods: A randomized, single-blinded trial in an outpatient rehabilitation clinic recruiting chronic KOA with pain ≥ 6 months over one year. Following randomization, subjects received either a single ACB or IASLI under ultrasound guidance. Numerical rating scale (NRS) scores for pain, and Knee Injury and Osteoarthritis Outcome Scores (KOOS) were recorded at baseline, 1 hour, 1 month, and 3 months postinjection. Results: Sixty-six knees were recruited; 2 were lost to follow-up. Age was normally distributed (P = 0.463), with more female subjects in both arms (P = 0.564). NRS scores improved significantly for both arms at 1 hour, with better pain scores for the IASLI arm (P = 0.416) at 1st month and ACB arm at 3rd month (P = 0.077) with larger effect size (Cohen's d = 1.085). Lower limb function improved significantly in the IASLI arm at 1 month; the ACB subjects showed greater functional improvement at 3 months (Cohen's d = 0.3, P = 0.346). Quality of life (QoL) improvement mirrored the functional scores whereby the IASLI group fared better at the 1st month (P = 0.071) but at the 3rd month the ACB group scored better (Cohen's d = 0.08, P = 0.710). Conclusions: ACB provides longer lasting analgesia which improves function and QoL in chronic KOA patients up to 3 months without any significant side effects.

• Journal of the Korean Society of Food Culture
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• v.35 no.6
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• pp.553-568
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• 2020

This systematic review and meta-analysis aimed to determine whether food intake is effective in preventing diseases related to cognitive impairment. We searched English databases namely MEDLINE, PubMed and ScienceDirect from 2000 to May 2020, and Korean databases namely RISS, KISS, and DBPIA from 1990 to May 2020. We divided the data into 15 groups using the food group classification of the Korean Nutrition Society (KNS). The effect size (Cohen's d) was estimated using a random-effect model, and a 95% confidence interval was calculated for each study. We included 17 cross-sectional studies and 7 cohort studies which involved 45,115 participants. As a result of analyzing the subgroups in the Asian population of both sexes, it was observed that grain intake has a protective effect against cognitive impairment. For females, pulses and fish also have a protective role against cognitive impairment. In the case of seaweed, a negative relationship was found with a moderate protective effect against cognitive impairment (Cohen's d:-0.533, 95% CI: -0.939, -0.126; p=0.010) in Korean studies. Dairy products are associated with an increased risk of cognitive impairment in the American and European population but drinking alcohol is associated with a lower impairment risk. These results provide a basis for formulating the dietary guidelines for preventing dementia for each country.

• The Journal of Korean Academy of Sensory Integration
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• v.19 no.2
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• pp.12-25
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• 2021

Objective : This study explored the effects of family-centered coaching using a sensory integration-based approach on the levels of performance and satisfaction for children with autism spectrum disorder (ASD). Methods : From April 16, 2020 to August 6, 2020, participants included 10 children with ASD, between the ages of three to six who met the inclusion criteria, and their guardians. I used the Canadian Occupational Performance Measure (COPM) to evaluate the children's levels of performance and satisfaction and the Goal Attainment Scaling (GAS) to evaluate their occupational performance. The experimental group (n=5) continued the sensory integration therapy while receiving their personalized family-centered coaching training for 60 minutes per week. This continued for four weeks via home visits and video calls. The control group (n=5) also continued to receive the sensory integration therapy while receiving sensory integration-based general counseling in relation to activity objectives. Results : Statistically significant differences were found in the scores of COPM performance and satisfaction and the GAS scores between the experimental group and the control group, before and after the intervention (p<.05). Statistically significant differences were found in score changes in COPM and GAS, between the two groups (p<.05). Cohen's d also showed a big effect size on the scores of COPM satisfaction (d=2.768) and the GAS scores (d=2.786). Conclusion : This study demonstrated that the sensory integration-based, family-centered coaching had more positive effects on the level of performance and satisfaction of children with ASD, than general counseling.