• Journal of Convergence for Information Technology
• /
• v.11 no.5
• /
• pp.138-149
• /
• 2021

Our society is developing exponentially, but schools are not keeping up with the pace of society's development, and they are not providing digital literacy education suitable for the growth and development of students. Thus, this study identified the actual conditions and problems of digital literacy education at school sites and sought the direction of development of digital literacy education. By identifying the current state of schools in which the 2015 curriculum is operated, we sought the direction of the development of digital literacy education for our school. First, old digital devices should be replaced, laptops or smart devices should be provided for each student, and internet access should be available throughout the school. Second, digital literacy education should be provided to teachers by providing various training opportunities.Third, coding education where you can express what you think as logical thinking, Software training should increase the level of the algorithmic domain that shows the computational thinking process of discovering problems and automating a given problem into a computer programming language, there is enough robot that can be seen operating the program, digital parish will need to be delivered.

• Nuclear Engineering and Technology
• /
• v.53 no.9
• /
• pp.3051-3057
• /
• 2021

The concrete is considered as an important radiation shielding material employed widely in nuclear reactors, particle accelerators, laboratory hot cells and other different radiation sources. The present research is dedicated to the shielding properties study of the ordinary concrete reinforced with different weight fractions of lead oxide micro/nano particles. Lead oxide particles were fabricated by chemical synthesis method and their properties including the average size, morphological structure, functional groups and thermal properties were characterized by XRD, FESEM-EDS, FTIR and TGA analysis. The gamma ray mass attenuation coefficient of concrete composites has been calculated and measured by means of the Monte Carlo simulation and experimental methods. The simulation process was based on the use of MCNP Monte Carlo code where the mass attenuation coefficient (μ/ρ) has been calculated as a function of different particle sizes and filler weight fractions. The simulation results showed that the employment of the lead oxide filler particles enhances the mass attenuation coefficient of the ordinary concrete, drastically. On the other hand, there are approximately no differences between micro and nano sized particles. The mass attenuation coefficient was increased by increasing the weight fraction of nanoparticles. However, a semi-saturation effect was observed at concentrations more than 10 wt%. The experimental process was based on the fabrication of concrete slabs filled by different weight fractions of nano lead oxide particles. The mass attenuation coefficients of these slabs were determined at different gamma ray energies using ²²Na, ¹³⁷Cs and ⁶⁰Co sources and NaI (Tl) scintillation detector. The experimental results showed that the HVL parameter of the ordinary concrete reinforced with 5 wt% of nano PbO particles was reduced by 64% at 511 keV and 48% at 1332 keV. Reasonable agreement was obtained between simulation and experimental results and showed that the employment of nano PbO particles is more efficient at low gamma energies up to 1Mev. The proposed concrete is less toxic and could be prepared in block form instead of toxic lead blocks.

• Nuclear Engineering and Technology
• /
• v.53 no.3
• /
• pp.949-959
• /
• 2021

The current study aims to explore the shielding properties of multi-component borate-based glass series. Seven glass-samples with composition of (80-y)H₃BO₃-10ZnO-10Na₂O-yBaO where (y = 0, 5, 10, 15, 20, 25 and 30 mol.%) were synthesized by melt-quench method. Various shielding features for photons, neutrons, and protons were determined for all prepared samples. XCOM, Phy-X program, and SRIM code were performed to determine and explain several shielding properties such as equivalent atomic number, exposure build-up factor, specific gamma-ray constants, effective removal cross-section (Σ_R), neutron scattering and absorption, Mass Stopping Power (MSP) and projected range. The energy ranges for photons and protons were 0.015-15 MeV and 0.01-10 MeV, respectively. The mass attenuation coefficient (μ/ρ) was also determined experimentally by utilizing two radioactive sources (¹⁶⁶Ho and ¹³⁷Cs). Consistent results were obtained between experimental and XCOM values in determining μ/ρ of the new glasses. The addition of BaO to the glass matrix led to enhance the μ/ρ and specific gamma-ray constants of glasses. Whereas the remarkable reductions in Σ_R, MSP, and projected range values were reported with increasing BaO concentrations. The acquired results nominate the use of these glasses in different radiation shielding purposes.

• Journal of Convergence for Information Technology
• /
• v.11 no.4
• /
• pp.122-129
• /
• 2021

As the total organic carbon (TOC) becomes a new water quality standard as an organic matter (OM) index for public sewage treatment facilities (PSTFs) in Korea from 2021, a comparison study needs to be conducted by examining the correlation between TOC and the existing OM indices (DOC, BOD5, CODMn, CODCr). 500 PSTFs were categorized by process configuration and capacity, and correlation between OM indices in influent and effluent was analyzed. The CODMn/TOC showed higher correlation than other OM indices. This results can be used to basic data for various research associated with TOC.

• Journal of Convergence for Information Technology
• /
• v.11 no.9
• /
• pp.84-93
• /
• 2021

The purpose of this study is to analyze whether the spread of COVID-19 infectious diseases acts as a fear to investors and affects the direction and volatility of stock returns. The investor fear index was proposed using the domestic confirmed patient information of COVID-19, and the influence on stock prices was empirically analyzed. The direction and volatility models of stock prices used the Granger causality and GARCH models, respectively. The results of empirical analysis using the KOSPI index from February 20, 2020 to June 30, 2021 are as follows: First, the COVID-19 fear index showed causality to future stock prices. Second, the COVID-19 fear index has a negative effect on the volatility of KOSPI index returns. In future studies, it is necessary to document the cause by using individual business performance and stock price instead of the stock index.

• Journal of Convergence for Information Technology
• /
• v.11 no.1
• /
• pp.128-135
• /
• 2021

The possibility and effectiveness of cryopreservation was determined to assess survival rates and improve stock management of thawed embryos of Manila clam, Ruditapes philippinarum. The ideal freezing rates were designed and tested to allow cryoprotectants to equilibrate across the membrane during freezing. Survival rates ranging from 0 to 64.3% were obtained using a stepwise freezing protocol compared with 82.3% control rates. Embryos of Ruditapes philippinarum were equilibrated in 2 CPAs plus sea water for 10 min at 25℃ and then cooled at -1℃/min from 20℃ to -12℃. Straws containing more than 100 embryos were held at 12℃ for 5 min allowing equilibration after seeding and slowly cooled at 2℃/min. to -35℃ for 30 min for equilibration before quenching in liquid nitrogen. Dimethyl sulfoxide (DMSO) is the best cryoprotectant indicated for embryos of R. philippinarum with a survival rate of 64.3±3.28% in the presence of 2.0 M DMSO.

• Journal of Convergence for Information Technology
• /
• v.10 no.12
• /
• pp.166-174
• /
• 2020

Cosmetic functional ingredients are products of emotional convergence technology. Unlike pharmaceuticals, it is very important that cosmetics ingredients contain emotional attractiveness because they are household products that have limitations in their effectiveness. Ginseng has long been used as a major prescription of oriental medicine for human health. Detailed records such as the origin and propagation of ginseng can lead to various cosmetical application of ginseng as an emotional convergence ingredients that utilizes the authenticity and excellence of ginseng as an asset of K-beauty. In the unfortunate reality that the first records of ginseng use depend on ancient Chinese literature, it is very meaningful to describe and leave the records of ginseng used in the field of beauty. This study examined the general historical records needed for the study of the cosmetics application of ginseng and the recent findings of ginsenoside in the area of skin function, and provided basic data that can be applied to new cosmetics development research.

• Journal of Convergence for Information Technology
• /
• v.11 no.1
• /
• pp.216-224
• /
• 2021

This study analyzes the differences in perception of cosmetic quality (safety, stability, functionality, usability) and satisfaction according to consumer characteristics, targeting 317 men and women from their 18 to 50s who use cosmetics in Seoul and Gyeonggi Province, and the differences in effect of cosmetic quality perception on satisfaction according to side effects experience was analyzed. Among the cosmetic quality factors, the usability was satisfied, but the perception of safety, stability, and functionality was low, so overall quality improvement was necessary. In particular, the quality perception and satisfaction by men and 40s was low, so a customized solution was needed for this. In the order of usability and functionality, to both those experiencing or not side effect, had a significant positive effect on the satisfaction level, and the improvement of usability and functional awareness was the main factor that increased satisfaction. Improving product quality and supplementing factors that positively influence consumer perception are thought to be of great help in improving quality perception and satisfaction.

• Journal of Convergence for Information Technology
• /
• v.10 no.12
• /
• pp.22-30
• /
• 2020

With the development of information and communication technology, DDoS and DRDoS continue to become security issues, and gradually develop into advanced techniques. Recently, IT companies have been threatened with DRDoS technology, which uses protocols from normal servers to exploit as reflective servers. Reflective traffic is traffic from normal servers, making it difficult to distinguish from security equipment and amplified to a maximum of Tbps in real-life cases. In this paper, after comparing and analyzing the DNS amplification and Memcached amplification used in DRDoS attacks, a countermeasure that can reduce the effectiveness of the attack is proposed. Protocols used as reflective traffic include TCP and UDP, and NTP, DNS, and Memcached. Comparing and analyzing DNS protocols and Memcached protocols with higher response sizes of reflective traffic among the protocols used as reflective traffic, Memcached protocols amplify ±21% more than DNS protocols. The countermeasure can reduce the effectiveness of an attack by using the Memcached Protocol's memory initialization command. In future studies, various security-prone servers can be shared over security networks to predict the fundamental blocking effect.

• Journal of Convergence for Information Technology
• /
• v.10 no.12
• /
• pp.191-200
• /
• 2020

This study was conducted to identify the oral health status and management behavior and dental use behavior according to the level of education and income of the elderly, and to present the supporting data to prepare policies and systems for the promotion of elderly oral health. The data survey was conducted on 224 elderly people living in the Daejeon area from August 19, 2019 to October 25, 2019, and the collected data were analyzed by chi-square test and logistic regression analysis. As a result, oral health status and management behavior showed significant differences according to education and income level in denture use, implant use, oral hygiene product use, oral health education experience, and oral health management method. There was a significant difference in dental use behavior according to education and income level, and age, education level, implant use, and the main reasons for dental use were found to be factors affecting dental use. Therefore, it is expected that the quality of life of the elderly's oral health can be improved by preparing an institutional plan at the national that considers education and income level based on this study.