• The Journal of the Convergence on Culture Technology
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• v.9 no.6
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• pp.627-636
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• 2023

This study was conducted to lay the basis of the need of the self-directed learning ability, critical thinking, communicative ability, problem solving skills for nursing students by confirming the effect of problem based learning classes of nursing students. The data collection period was from March 1 to June 7, 2022. It was provided problem based learning classes to 165 nursing students located at B city. Problem based learning classes were conducted at total of 14 times, and 100 minutes/time. The collected data were analyzed using the frequency and percentage, Cronbach's α, mean and standard deviation with the SPSS Win 21.0 program, and the effectiveness verification of problem based learning classes was analyzed with a paired t-test. As a result of the effectiveness of the problem based learning class, the self-directed learning ability(t=-2.08, p=.039), critical thinking(t=-2.49, p=.014), communicative ability(t=-4.90, p<.001), problem solving skills(t=-4.84, p<.001) of nursing students who took 14 weeks of problem based learning was enhanced. Based on the results of this study, by applying it in various ways to first-year nursing students, it will be possible to use them to improve their competence, major satisfaction, and adapt to college life.

• Composites Research
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• v.36 no.5
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• pp.289-296
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• 2023

In this study, we investigated the electromagnetic properties and microwave absorption characteristics of M-type hexagonal ferrites, which are known as millimeter-wave absorbing materials, according to their calcination temperature. The M-type ferrites synthesized using a molten salt-based sol-gel method exhibited a single-phase M-type crystal structure at calcination temperatures above 850℃. The synthesized particle size increased as well with the calcination temperature. Saturation magnetization increased gradually with increasing calcination temperature, but coercivity reached a maximum at 1050℃ and then rapidly decreased. After preparing a thermoplastic polyurethane (TPU) composite containing 70 wt% of M-type ferrites, we measured the complex permittivity and permeability in the Q-band (33-50 GHz) and V-band (50-75 GHz) frequency ranges, where ferromagnetic resonance occurred. Strong magnetic loss from ferromagnetic resonance occurred in the 50 GHz band for all composite samples. Based on the measured results, we calculated the reflection loss of the TPU/M-type ferrite composite. By calculating the reflection loss of the M-type ferrite composite, the M-type ferrite calcined at 1250℃ showed excellent electromagnetic wave absorption performance of more than -20 dB at 52 GHz with a thickness of about 0.5 mm.

• Nuclear Engineering and Technology
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• v.55 no.10
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• pp.3874-3897
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• 2023

A high-fidelity computational fluid dynamics (CFD) analysis was performed using the Large Eddy Simulation (LES) model for the lower plenum of the High-Temperature Test Facility (HTTF), a ¼ scale test facility of the modular high temperature gas-cooled reactor (MHTGR) managed by Oregon State University. In most next-generation nuclear reactors, thermal stress due to thermal striping is one of the risks to be curiously considered. This is also true for HTGRs, especially since the exhaust helium gas temperature is high. In order to evaluate these risks and performance, organizations in the United States led by the OECD NEA are conducting a thermal hydraulic code benchmark for HTGR, and the test facility used for this benchmark is HTTF. HTTF can perform experiments in both normal and accident situations and provide high-quality experimental data. However, it is difficult to provide sufficient data for benchmarking through experiments, and there is a problem with the reliability of CFD analysis results based on Reynolds-averaged Navier-Stokes to analyze thermal hydraulic behavior without verification. To solve this problem, high-fidelity 3-D CFD analysis was performed using the LES model for HTTF. It was also verified that the LES model can properly simulate this jet mixing phenomenon via a unit cell test that provides experimental information. As a result of CFD analysis, the lower the dependency of the sub-grid scale model, the closer to the actual analysis result. In the case of unit cell test CFD analysis and HTTF CFD analysis, the volume-averaged sub-grid scale model dependency was calculated to be 13.0% and 9.16%, respectively. As a result of HTTF analysis, quantitative data of the fluid inside the HTTF lower plenum was provided in this paper. As a result of qualitative analysis, the temperature was highest at the center of the lower plenum, while the temperature fluctuation was highest near the edge of the lower plenum wall. The power spectral density of temperature was analyzed via fast Fourier transform (FFT) for specific points on the center and side of the lower plenum. FFT results did not reveal specific frequency-dominant temperature fluctuations in the center part. It was confirmed that the temperature power spectral density (PSD) at the top increased from the center to the wake. The vortex was visualized using the well-known scalar Q-criterion, and as a result, the closer to the outlet duct, the greater the influence of the mainstream, so that the inflow jet vortex was dissipated and mixed at the top of the lower plenum. Additionally, FFT analysis was performed on the support structure near the corner of the lower plenum with large temperature fluctuations, and as a result, it was confirmed that the temperature fluctuation of the flow did not have a significant effect near the corner wall. In addition, the vortices generated from the lower plenum to the outlet duct were identified in this paper. It is considered that the quantitative and qualitative results presented in this paper will serve as reference data for the benchmark.

• Journal of Korean Tunnelling and Underground Space Association
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• v.26 no.2
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• pp.91-111
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• 2024

Most of utility cable tunnels are constructed utilizing shield TBM as part of the underground transmission line project. The TBM chamber is the only space inside the tunnel that encounters rock and soil, and is the place with the highest frequency of accident exposure, such as collapse and collision accidents. Since there is currently no way to measure the disc cutter wear from outside the chamber, frequent inspection by workers is essential. Accordingly, in this study, in order to prevent safety accidents inside the TBM chamber and expect the effect of shortening the construction period by reducing the number of chamber openings, the concept of disk cutter wear measurement technology was established and a prototype was produced. By considering prior technology and determining that magnetic sensors are most suitable for the excavation environment, wear measurement sensor package were developed integrating magnetic sensors, wireless communication modules, power supply, external casing, and monitoring systems. To verify the performance of the prototype in an actual excavation environment, a full-scale tunnelling test was performed using a 3.6 m EPB shield TBM. Based on the full-scale tests, five prototypes were operated normally among eight prototypes. It was analyzed that sensor measurement, wireless communication, and durability performance were secured within a maximum thrust of 3,000 kN and a rotation speed of 1.5 RPM.

• BMB Reports
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• v.57 no.1
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• pp.60-65
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• 2024

The CRISPR-Cas9 system has significantly advanced regenerative medicine research by enabling genome editing in stem cells. Due to their desirable properties, mesenchymal stem cells (MSCs) have recently emerged as highly promising therapeutic agents, which properties include differentiation ability and cytokine production. While CRISPR-Cas9 technology is applied to develop MSC-based therapeutics, MSCs exhibit inefficient genome editing, and susceptibility to plasmid DNA. In this study, we compared and optimized plasmid DNA and RNP approaches for efficient genome engineering in MSCs. The RNP-mediated approach enabled genome editing with high indel frequency and low cytotoxicity in MSCs. By utilizing Cas9 RNPs, we successfully generated B2M-knockout MSCs, which reduced T-cell differentiation, and improved MSC survival. Furthermore, this approach enhanced the immunomodulatory effect of IFN-r priming. These findings indicate that the RNP-mediated engineering of MSC genomes can achieve high efficiency, and engineered MSCs offer potential as a promising therapeutic strategy.

• The Journal of Korean Obstetrics and Gynecology
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• v.37 no.1
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• pp.75-88
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• 2024

Objectives: This study aimed to identify the current use of Korean medicine for obesity and its effect for women in climacteric period. Methods: We studied women aged 45-55 who visited Daejeon Korean medicine Hospital of Daejeon University to lose body weight from January 1, 2021 to December 31, 2022 via an analysis of the medical records. The treatment duration was continuous for more than 2 weeks, and a body composition was measured by Inbody 770 at 2 to 4 weeks after the first visit. Results: 28 patients were finally selected and their average age was 49.32±3.38 years. Based on the body mass index (BMI) classification, 19 were in the 1st obesity group, 5 in the 2nd obesity group, 3 in the overweight group and 1 in the normal group. Patients usually complained comcomitant symptoms, and the symptoms of menopausal disorder was the most frequent. The average treatment duration was 3.68±0.67 weeks and the average treatment frequency was 3.93±0.98 times. All patients took herbal medicines Gambi-tang and 23 took modified fasting therapy including Gamro-su. 14 were treated by whole body far-infrared therapy and 6 were gotten partial obesity treatment. Among patients treated for accompanying symptoms, menopausal disorders were the most common (35.71%), and herbal medicine such as Gamisoyou-san, Hominis Placenta Pharmacopuncture, moxibustion, and cupping were used. After treatment, on average, body composition changed significantly; body weight 3.28±1.82 kg, BMI 1.36±1.04 kg/m², body fat 1.70±1.67 kg, skeletal muscle mass 0.81±0.91 kg, abdominal circumference 2.04±2.6 cm, and visceral fat area 8.91±12.83 cm². Conclusions: We analyzed general characteristics, BMI distribution, types of Korean medicine treatment and change of body composition. This study could be used as reference to provide practical data of treatment for obese women in climacteric period.

• Industry Promotion Research
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• v.9 no.1
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• pp.179-187
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• 2024

This study aims to develop policies and programs to improve self-differentiation that will have an impact on establishing a positive view of marriage among college students by examining and confirming the impact of college students' self-differentiation on their views on marriage among college students in early adulthood. This is an attempted research study. For this purpose, a self-report online survey was conducted and analyzed among 204 college students attending a university in northern Gyeonggi Province. The analysis method used SPSS 25.0 program to calculate internal consistency, frequency analysis to identify the general characteristics of the research subject, descriptive statistical analysis to determine the level of the research variable, and differences in research variables according to the characteristics of the research subject. To find out, an independent samples t-test, analysis of variance, and post hoc test were conducted, and analysis using SPSS Process Macro was conducted to verify the mediation effect. The results of the analysis showed a positive (+) correlation between self-differentiation and views on marriage, which suggests that self-differentiation has a significant impact on establishing a positive view on marriage, and for this purpose, it is necessary to establish a positive view on marriage among college students. To this end, we aimed to provide basic data to support education for healthy families through national policy.

• The Transactions of the Korea Information Processing Society
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• v.13 no.3
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• pp.91-101
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• 2024

The utilization of container virtualization technology ensures the consistency and portability of data-intensive and memory volatile workflows. Kubernetes serves as the de facto standard for orchestrating these container applications. Cloud users often overprovision container applications to avoid container restarts caused by resource shortages. However, overprovisioning results in decreased CPU and memory resource utilization. To address this issue, oversubscription of container resources is commonly employed, although excessive oversubscription of memory resources can lead to a cascade of container restarts due to node memory scarcity. Container restarts can reset operations and impose substantial overhead on containers with high memory volatility that include numerous stateful applications. This paper proposes a technique to mitigate container restarts in a memory oversubscription environment based on Kubernetes. The proposed technique involves identifying containers that are likely to request memory allocation on nodes experiencing high memory usage and temporarily pausing these containers. By significantly reducing the CPU usage of containers, an effect similar to a paused state is achieved. The suspension of the identified containers is released once it is determined that the corresponding node's memory usage has been reduced. The average number of container restarts was reduced by an average of 40% and a maximum of 58% when executing a high memory volatile workflow in a Kubernetes environment with the proposed method compared to its absence. Furthermore, the total execution time of a container workflow is decreased by an average of 7% and a maximum of 13% due to the reduced frequency of container restarts.

• The Journal of the Convergence on Culture Technology
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• v.10 no.3
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• pp.47-52
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• 2024

The purpose of this study was to examine the relationship between children's self-esteem, peer attachment, parenting attitudes, and children's grit, and to specifically identify the influence of children's self-esteem, peer attachment, and parenting attitudes on children's grit. The characteristics of the survey subjects were identified through frequency analysis and descriptive statistics analysis of the 11th year of the Korea Children's Panel (2018) data, and Pearson's moment correlation coefficient was calculated for correlation analysis between major variables. Multiple regression analysis was conducted to examine the influence of children's self-esteem, peer attachment, and parenting attitudes on children's grit. The research results are as follows. First, children's self-esteem, peer attachment, and parenting attitudes were found to be positively correlated. Second, the child's self-esteem was found to have a positive influence on the child's grit, and among the peer attachment sub-variables, peer trust was found to have an influence, and among the sub-factors of parenting attitude, 'mother' affection/involvement, 'father' Democratic relationships were found to have an effect. In other words, it can be seen that children's self-esteem at the personal level, peer trust at the school level, and maternal affection and paternal relationship at the family level are useful variables that strengthen children's grit. Accordingly, in order to improve children's grit level, we must consider promotion measures through intervention and support at a multifaceted level.

• Journal of Nutrition and Health
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• v.57 no.2
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• pp.211-227
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• 2024

Introduction: Seaweed is a sustainable and underexplored source of bioactive compounds with potent anti-inflammatory activities. However, studies on the interaction between seaweed and genes on inflammation are limited. Purpose: We aimed to evaluate the relationships between seaweed consumption and the polygenic risk scores (PRS) and their interactions with high-sensitivity C-reactive protein (hs-CRP) levels. Methods: Information on seaweed consumption was collected using a food frequency questionnaire, which included laver, kelp, and sea mustard among the items consumed. A total of 31 hs-CRP-related single nucleotide polymorphisms (SNPs) were selected using genome-wide association studies and clumping analysis, and the individual PRS were calculated by weighting the effect size of each allele in the selected SNPs of 39,369 middle-aged (≥40 years) Koreans using the Korean Genome and Epidemiology Study (KoGES)-Health Examinees (HEXA) cohort data. To investigate the interaction between seaweed intake and the PRS on hs-CRP levels >1 mg/L, hazard ratios (HRs) and 95% confidence intervals (CIs) were assessed using multivariable Cox proportional hazards models. Results: During a mean follow-up period of 4.8 years, we recorded 436 patients with elevated hs-CRP levels. Women in the highest tertile of the PRS with the lowest quartile of seaweed intake had an increased incidence of elevated hs-CRP levels compared with women in the lowest tertile of the PRS with the lowest seaweed intake quartile (HR 2.34, 95% CI 1.23-4.45). No significant association was observed among the men. Conclusion: In conclusion, we identified a new interaction between the PRS, seaweed intake, and inflammation in Korean women, and this study suggests that the interaction between the identification of genetic predisposition and dietary seaweed intake may have an impact on determining the risk of developing hyperinflammation in the future.