• Nuclear Engineering and Technology
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• v.53 no.12
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• pp.3879-3891
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• 2021

A heat pipe residual heat removal system is proposed to be incorporated into the reactor driven subcritical (RDS) facility, which has been proposed by MIT Nuclear Reactor Laboratory for testing and demonstrating the Fluoride-salt-cooled High-temperature Reactor (FHR). It aims to reduce the risk of the system operation after the shutdown of the facility. One of the main components of the system is an air-cooled heat pipe heat exchanger. The alkali-metal high-temperature heat pipe was designed to meet the operation temperature and residual heat removal requirement of the facility. The heat pipe model developed in the previous work was adopted to simulate the designed heat pipe and assess the heat transport capability. 3D numerical simulation of the subcritical facility active zone was performed by the commercial CFD software STAR CCM + to investigate the operation characteristics of this proposed system. The thermal resistance network of the heat pipe was built and incorporated into the CFD model. The nominal condition, partial loss of air flow accident and partial heat pipe failure accident were simulated and analyzed. The results show that the residual heat removal system can provide sufficient cooling of the subcritical facility with a remarkable safety margin. The heat pipe can work under the recommended operation temperature range and the heat flux is below all thermal limits. The facility peak temperature is also lower than the safety limits.

• Earthquakes and Structures
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• v.22 no.1
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• pp.25-38
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• 2022

The RC private constructions represent a large part of the housing stock in the north part of Algeria. For various reasons, they are mostly built without any seismic considerations and their seismic vulnerability remains unknown for different levels of seismic intensity possible in the region. To support future seismic risk mitigation efforts in northern Algeria, this document assesses the seismic vulnerability of typical private RC constructions built after the Boumerdes earthquake (May 21, 2003) without considering existing seismic regulation, through the development of analytical fragility curves. The fragility curves are developed for four representative RC frames in terms of slight, moderate, extensive, and complete damage states suggested in HAZUS-MH 2.1, using nonlinear time history analyses. The numerical simulation of the nonlinear seismic response of the structures is performed using the SeismoStruct software. An original intensity measure (IM) is proposed and used in this study. It is the zone acceleration coefficient "A", through which the seismic hazard level is represented in the Algerian Seismic Regulations. The efficiency, practicality, and proficiency of the choice of IM are demonstrated. Incremental dynamic analyses are conducted under fifteen ground motion accelerograms compatible with the elastic target spectrum of the Algerian Seismic Regulations. In order to cover all the seismic zones of northern Algeria, the accelerograms are scaled from 0.1 to 2.5 in increments of 0.1. The results mainly indicate that private constructions built after the Boumerdes earthquake in the moderate and high seismic zones with four (04) or more storeys are highly vulnerable.

• Child Health Nursing Research
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• v.29 no.2
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• pp.111-127
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• 2023

Purpose: This study investigated the effects of healthy lifestyle interventions (HLSIs) on health-related quality of life (HR-QoL) in childhood and adolescent cancer survivors (CACS). Methods: Major databases were searched for English-language original articles published between January 1, 2000 and May 2, 2021. Randomized controlled trials (RCTs) and non-RCTs were included. Quality was assessed using the revised Cochrane risk-of-bias tool, and a meta-analysis was conducted using RevMan 5.3 software. Results: Nineteen studies were included. Significant effects on HR-QoL were found for interventions using a multi-modal approach (exercise and education) (d=-0.46; 95% confidence interval [CI]=-0.84 to -0.07, p=.02), lasting not less than 6 months (d=-0.72; 95% CI=-1.15 to -0.29, p=.0010), and using a group approach (d=-0.46; 95% CI=-0.85 to -0.06, p=.02). Self-efficacy showed significant effects when HLSIs provided health education only (d=-0.55; 95% CI=-0.92 to -0.18; p=.003), lasted for less than 6 months (d=-0.40; 95% CI=-0.69 to -0.11, p=.006), and were conducted individually (d=-0.55; 95% CI=-0.92 to -0.18, p=.003). The physical outcomes (physical activity, fatigue, exercise capacity-VO₂, exercise capacity-upper body, body mass index) revealed no statistical significance. Conclusion: Areas of HLSIs for CACS requiring further study were identified, and needs and directions of research for holistic health management were suggested.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.26 no.5
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• pp.231-238
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• 2023

Purpose: This systematic review and meta-analysis aimed to compare endoscopy as primary versus secondary prophylaxis to prevent future bleeding in children with esophageal varices. Methods: A systematic literature search using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses method was conducted using the Scopus, PubMed, and Cochrane databases for relevant studies on the outcome of rebleeding events after endoscopy in primary prophylaxis compared to that in secondary prophylaxis. The following keywords were used: esophageal varices, children, endoscopy, primary prophylaxis and bleeding. The quality of eligible articles was assessed using the Newcastle-Ottawa Scale and statistically analyzed using RevMan 5.4 software. Results: A total of 174 children were included from four eligible articles. All four studies were considered of high-quality based on the Newcastle-Ottawa Quality Assessment Scale. Patients who received primary prophylaxis had 79% lower odds of bleeding than those who received secondary prophylaxis (odds ratio, 0.21; 95% confidence interval [CI], 0.07-0.66; I²=0%, p=0.008). Patients in the primary prophylaxis group underwent fewer endoscopic procedures to eradicate varices than those in the secondary prophylaxis group, with a mean difference of 1.73 (95% CI, 0.91-2.56; I²=62%, p<0.0001). Conclusion: Children with high-risk varices who underwent primary prophylaxis were less likely to experience future bleeding episodes and required fewer endoscopic procedures to eradicate the varices than children who underwent secondary prophylaxis.

• Journal of Information Science Theory and Practice
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• v.10 no.spc
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• pp.56-65
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• 2022

Korea Institute of Science and Technology Information (KISTI) is a Worldwide LHC Computing Grid (WLCG) Tier-1 center mandated to preserve raw data produced from A Large Ion Collider Experiment (ALICE) experiment using the world's largest particle accelerator, the Large Hadron Collider (LHC) at European Organization for Nuclear Research (CERN). Physical medium used widely for long-term data preservation is tape, thanks to its reliability and least price per capacity compared to other media such as optical disk, hard disk, and solid-state disk. However, decreasing numbers of manufacturers for both tape drives and cartridges, and patent disputes among them escalated risk of market. As alternative to tape-based data preservation strategy, we proposed disk-only erasure-coded archival storage system, Custodial Disk Storage (CDS), powered by Exascale Open Storage (EOS), an open-source storage management software developed by CERN. CDS system consists of 18 high density Just-Bunch-Of-Disks (JBOD) enclosures attached to 9 servers through 12 Gbps Serial Attached SCSI (SAS) Host Bus Adapter (HBA) interfaces via multiple paths for redundancy and multiplexing. For data protection, we introduced Reed-Solomon (RS) (16, 4) Erasure Coding (EC) layout, where the number of data and parity blocks are 12 and 4 respectively, which gives the annual data loss probability equivalent to 5×10^-14. In this paper, we discuss CDS system design based on JBOD products, performance limitations, and data protection strategy accommodating EOS EC implementation. We present CDS operations for ALICE experiment and long-term power consumption measurement.

• Journal of the Korean Society of Radiology
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• v.17 no.3
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• pp.459-464
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• 2023

Due to the development of advanced technology, a lot of digital radiographic equipment has been developed, which is very helpful for accurate diagnosis and treatment, and it is very important to train personnel who have acquired professional knowledge in order to use it safely and effectively. Students are exposed to the risk of radiation exposure in radiography training using diagnostic X-ray equipment, and some educational institutions do not use X-ray equipment due to management difficulties in accordance with the Nuclear Safety Act. As a solution to this, this study developed a medical radiation simulator for education that does not generate radiation by using a vision sensor and self-developed software. Through this, educational institutions can reduce the burden of administrative implementation according to the law, and students can obtain a high level of educational effects in a healthy practice environment without radiation exposure.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.33 no.1
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• pp.45-50
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• 2023

Roblox, the world's No. 1 metaverse platform, has more than 3 billion subscription accounts and more than 150 millionmonthly active users (MAU). Despite such high interest in metaverse, existing studies on analyzing the risk of cyberattacks and security in the metaverse environment is insufficient. Therefore, in this paper, we propose a new steganography-basedcovert communication method in Roblox. In our proposed method, a secret message is hidden into an image by using a function provided in the Roblox Experience environment and then the image is automatically stored in the RobloxExperience participants' devices (PC or Smartphone) so that a malicious software can extract the hidden message fromthe image. By our experiments in the Roblox metaverse environment, we validated our proposed method works and thus want to inform our proposed method can be used in various cyberattacks and crimes such as the spread of secret commands, the establishment of a steganography botnet, and the mass distribution of malicious malware in metaverse platforms.

• The Research Journal of the Costume Culture
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• v.31 no.3
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• pp.330-345
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• 2023

This study aimed to categorize consumers using super app functional characteristics to identify demographic differences, and analyze shopping orientations by consumer type. This data can be used by fashion and beauty companies for product planning and marketing strategies. To categorize super app consumers, data were analyzed with SPSS v.26.0 software using frequency, factor, reliability K-mean cluster, and distributed analyses, one-way-ANOVAs, and Scheffe verification. Cross-analysis was conducted to correlate super app consumer types with demographic characteristics. One-way-ANOVAs and Scheffe verification were used to analyze the differences in shopping preferences between super app consumer groups. As a result of our analyses, super app consumers were classified into four types: the ration type, the low-use type, the multifunction type, and the habit type. There were statistically significant differences between these types in age, occupation, marital status, average monthly household income, and shopping impact factors. Five super app user shopping orientations were identified: brand pursuit, pleasure pursuit, trend pursuit, risk perception, and economic orientation. The differences in the preferred orientation between super app consumer types were found to be statistically significant. The majority of respondents were multifunction type consumers. This group used the super app most frequently and effectively. They also demonstrated the highest scores for all five of the shopping orientations. The classification of consumer types in this study will allow the fashion and beauty industries to utilize super apps for more targeted product design and marketing.

• The Journal of Korean Medicine
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• v.44 no.2
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• pp.201-201
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• 2023

Objectives: Cupping therapy (CT) has been widely used in traditional medicine worldwide for various indications, including stroke. The aim of this study was to systematically review the clinical evidence of CT for stroke. Methods: To identify randomized controlled trials (RCTs) reporting the effectiveness and/or safety of CT, seven databases including PubMed, EMBASE, and Cochrane Library were searched for articles published from January 2000 to February 2021 without language restrictions. Meta-analysis was performed using Review Manager 5.4 software and the results were presented as mean difference (MD) or standard mean difference (SMD) for continuous variables and odds ratio (OR) for diverse variables with 95% confidence intervals (CIs). Assessment of the methodological quality of the eligible trials was conducted using the Cochrane Collaboration tool for risk of bias in RCTs. Results: Twenty-two RCTs with 1653 participants were included in the final analysis. CT provided additional benefit in improving upper limb motor function (Fugl-Meyer assessment for upper limb motor function, MD 6.91, 95% CI 4.64 to 1.67, P<0.00001) and spasticity (response rate, OR 3.28, 95% CI 1.31 to 8.22, P=0.08) in stroke survivors receiving conventional medical treatment. These findings were supported with a moderate level of evidence. CT did not significantly increase the occurrence of adverse events. Conclusions: This study demonstrated the potential of CT to be beneficial in managing a variety of complications in stroke survivors. However, to compensate for the shortcomings of the existing evidence, rigorously designed large-scale RCTs are warranted in the future.

• Journal of The Korean Society of Integrative Medicine
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• v.11 no.4
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• pp.1-15
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• 2023

Purpose : This study investigates the effectiveness of digital therapy for stroke patients in Korea. Methods : A comprehensive database search was performed using KCI, Science on, e-article, RISS, KISS and Korea OpenMed databases for randomized controlled trials (RCTs) that studied the effects of digital therapy on patients who had a stroke. This study includes RCTs published from January 2000 to July 15, 2022, which fulfilled the inclusion and exclusion criteria. A total 697 studies were screened and 30 studies were included in the final analysis. Methodological quality was assessed with the Cochrane's RoB (risk of bias) tool. Meta-analysis was performed using CMA 4.0 software. Results : A total of 56 effect sizes were calculated from the 30 selected studies. As a result of the analysis, the overall effect size of digital therapy was .59 (95 % CI=.43-.74). When classified according to type of intervention, VR (virtual reality) (g=.58, 95 % CI=.40-.75), and CACR (computer assisted cognitive rehabilitation) (g=.62, 95 % CI=.30-.95) were statistically significant. VR showed medium to large effect sizes in cognitive function (g=.78, 95 % CI=.20-1.37), psychosocial function (g=.63, 95 % CI=.20-1.07), and physical function (g=.61, 95 % CI=.38-.83). In the CACR, there was a large effect size in cognitive function (g=.84, 95 % CI=.52-1.15), but there was no significant difference in psychosocial function. Also, there was no significant difference between the two interventions in activities of daily living and no significant difference in the effect size of both interventions according to the intervention session. Furthermore, medium to large effect sizes were found for subacute and chronic stroke patients according to the duration of disease. Conclusion : This study presents evidence that digital therapy has a positive effect on various functions of stroke patients in Korea. The researchers expect to actively accept the new paradigm of digital therapy and continue to apply digital therapy in clinical practice.