• Journal of Science Education
• /
• v.45 no.1
• /
• pp.90-104
• /
• 2021

This study conducted an online survey to understand what elementary school teachers think about the learning contents of elementary science education subjects needed to train elementary science teachers suitable for the era of the 4th Industrial Revolution. The results are as follows: First, there were many elementary school teachers who thought that the current learning content of elementary science education was not suitable for the era of the 4th Industrial Revolution and that it needed to modify the learning content. Many of the teachers said that the learning content of the subject did not include the characteristics of the 4th Industrial Revolution, but also did not reflect the changes of the times and remained in the past. Second, the content that elementary school teachers thought was important in training elementary school teachers suitable for the era of the 4th Industrial Revolution was mainly related to the interests and curiosity of students, and scientific experiments or inquiry. On the contrary, the items that they thought should be deleted or reduced included science learning theory, science teaching/learning model, nature of science, and guidance for gifted children. Third, the contents that elementary school teachers thought needed to be added as learning content of elementary science education subjects were SSI education, science education-related social change and future prediction, advanced science technology, STEAM guidance, and integrated education within the science field. Fourth, in order to train elementary school teachers suitable for the era of the 4th Industrial Revolution, the contents that they thought should be introduced first as learning content of elementary science education subjects were SSI education, integrated education within the science field, STEAM guidance, and core competencies. Other contents that need to be introduced were software education, safety education, and project learning methods.

• Journal of Korea Entertainment Industry Association
• /
• v.14 no.3
• /
• pp.463-473
• /
• 2020

This study was conducted to provide basic data to find measures to alleviate the job stress of 119 Emergency Medical Technicians by identifying the mediating effect of resilience for life care in the relationship between stress coping and job stress of 119 Emergency Medical Technicians. The data for this study were collected from October 5, 2019, to October 31, 2019. The subject was 205 119 Emergency Medical Technicians working in 119 safety centers located in G Metropolitan City. The collected data were analyzed by independent t-test, ANOVA, Scheffé test, Pearson's correlation coefficients, hierarchical multiple regression analysis, and Sobel test using the SPSS Statistics 21.0 program. As a result oh the study, The mediation effect of resilience was not statistically significant in the relationship between stress coping of seeking social support type and job stress; the mediation effect of resilience was not statistically significant in the relationship between stress coping of seeking positive thinking type and job stress. but, resilience was revealed that resilience completely mediates the relationship between problem-solving type and job stress, and partially mediates the relationship between avoidance type and job stress. The measures to reduce the job stress of 119 Emergency Medical Technicians derived from the above results are as follows. First, among the 119 Emergency Medical Technicians, problem-solving stress coping type 119 Emergency Medical Technicians need to reduce job stress through resilience improvement program. Second, avoidance stress coping type 119 Emergency Medical Technicians should take part in education programs that can reduce job stress in parallel with resilience improvement program.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.48 no.4
• /
• pp.321-330
• /
• 2022

This study attempted to establish an optimal multi-compound simultaneous analysis method that can secure reliable results for 15 - preservatives, 2 - sun screens and 1 - antioxidants of cosmetics using HPLC-PDA. Since the potential of hydrogen (pH) in the mobile phase affects the acid dissociation constant (pKa) of the preservatives, and the peak retention time shift and area change were observed. The peak separation condition was established by adjusting the pH to 0.1% H₃PO₄ addition (mL) when preparing the mobile phase. As a results of method validation, the linearity correlation coefficient (R²) of above 0.999 were obtained, and accuracy 87.9 ~ 101.1%, 0.1 ~ 7.6% precision for two types of cosmetics (cream and shampoo). It was found that the limit of detection (LOD) was 0.1 ~ 0.2 mg/kg and the limit of quantitation (LOQ) was 2.0 ~ 4.0 mg/kg. In addition, it was possible to simultaneously separate p-anisic acid, a natural compound that was difficult to separate in HPLC due to the small difference from methylparaben, a synthetic preservatives. Through this study, it will be effectively used to secure quality control and safety for compound that need restrictions on use cosmetics.

• Journal of the Korean Geotechnical Society
• /
• v.38 no.11
• /
• pp.107-118
• /
• 2022

The social need for stable hydrogen storage technologies that respond to the increasing demand for hydrogen energy is increasing. Among them, underground hydrogen storage is recognized as the most economical and reasonable storage method because of its vast hydrogen storage capacity. In Korea, low-depth hydrogen storage using artificial protective structures is being considered. Further, establishing corresponding safety standards and ground stability evaluation is becoming essential. This study evaluated the hydro-mechanical behavior of the ground during a hydrogen gas leak from a low-depth underground hydrogen storage facility through the HM coupled analysis model. The predictive reliability of the simulation model was verified through benchmark experiments. A parameter study was performed using a metamodel to analyze the sensitivity of factors affecting the surface uplift caused by the upward infiltration of high-pressure hydrogen gas. Accordingly, it was confirmed that the elastic modulus of the ground was the largest. The simulation results are considered to be valuable primary data for evaluating the complex analysis of hydrogen gas explosions as well as hydrogen gas leaks in the future.

• Informatization Policy
• /
• v.29 no.1
• /
• pp.84-102
• /
• 2022

Changes have been taking place in North Korea, which has been pushing for selective informatization with a priority on a system safety. North Korea has been developing its own mobile communication industry over the past decade by expanding base stations, producing smartphones on its own, and developing applications useful in real life. Recently, the introduction of 5G technology has been elevated to the status of a national agenda to be fostered as a key industry for national economic development. The time has arrived when the needs of North Korea, which has to advance technology, are aligned with the capabilities of South Korean mobile communication companies, which are seeking to new markets to overcome stagnant growth. The purpose of this paper is to illustrate a cooperative scenario for mobile communications companies between the two Koreas in the early stages of the 4th Industrial Revolution and its core technology 5G, while also making a timely proposal to position North Korea in the GVC. Mobile communications is a large-scale industry that can create synergies from inter-Korean economic cooperation by facilitating exchanges and cooperation between the two Koreas, inducing numerous derivative industries and driving job creation. Joint mobile communications activities with North Korea would be an effective cooperative aspect that can contribute to the economic prosperity of the entire Korean Peninsula.

• Nuclear Engineering and Technology
• /
• v.54 no.3
• /
• pp.842-848
• /
• 2022

Parametric studies of heat transfer and fluid flow are very important research of interest because the design and operation of fluid flow and heat transfer systems are guided by these parametric studies. The safety of the system operation and system optimization can be determined by decreasing or increasing particular fluid flow and heat transfer parameter while keeping other parameters constant. The parameters that can be varied in order to determine safe and optimized system include system pressure, mass flow rate, heat flux and coolant inlet temperature among other parameters. The fluid flow and heat transfer systems can also be enhanced by the presence of or without the presence of particular effects including gravity effect among others. The advanced Generation IV reactors to be deployed for large electricity production, have proven to be more thermally efficient (approximately 45% thermal efficiency) than the current light water reactors with a thermal efficiency of approximately 33 ℃. SCWR is one of the Generation IV reactors intended for electricity generation. High Performance Light Water Reactor (HPLWR) is a SCWR type which is under consideration in this study. One-eighth of a proposed fuel assembly design for HPLWR consisting of 7 fuel/rod bundles with 9 coolant sub-channels was the geometry considered in this study to examine the effects of system pressure and mass flow rate on wall and fluid temperatures. Gravity effect on wall and fluid temperatures were also examined on this one-eighth fuel assembly geometry. Computational Fluid Dynamics (CFD) code, STAR-CCM+, was used to obtain the results of the numerical simulations. Based on the parametric analysis carried out, sub-channel 4 performed better in terms of heat transfer because temperatures predicted in sub-channel 9 (corner subchannel) were higher than the ones obtained in sub-channel 4 (central sub-channel). The influence of system mass flow rate, pressure and gravity seem similar in both sub-channels 4 and 9 with temperature distributions higher in sub-channel 9 than in sub-channel 4. In most of the cases considered, temperature distributions (for both fluid and wall) obtained at 25 MPa are higher than those obtained at 23 MPa, temperature distributions obtained at 601.2 kg/h are higher than those obtained at 561.2 kg/h, and temperature distributions obtained without gravity effect are higher than those obtained with gravity effect. The results show that effects of system pressure, mass flowrate and gravity on fluid flow and heat transfer are significant and therefore parametric studies need to be performed to determine safe and optimum operating conditions of fluid flow and heat transfer systems.

• Korean Journal of Construction Engineering and Management
• /
• v.23 no.5
• /
• pp.43-55
• /
• 2022

Since assembled temporary equipment is widely used for construction work that should be carried out before this construction begins, it is essential to secure quality during assembly and prevent safety accidents caused by assembled temporary equipment after installation. However, it was investigated that most construction site managers are not aware of its importance, such as recognizing the quality management of assembled temporary equipment as a task of managing temporary structures that are dismantled after installation for this construction. The quality management work of assembled temporary equipment at the construction site is carried out in different ways for each construction site because there is no formalized procedure and the subject of performing. In addition, it is analyzed that the manager of the general construction company inspects and reflects the parts that need to be inspected without evidence, so transparency is not guaranteed and the result leads to a serious disaster. Therefore, the purpose of this study is to establish a document preparation-oriented system that provides systematic quality evaluation and management procedures for securing the quality of assembled temporary equipment, develops a checklist for quality evaluation and management, and supports history management on the web.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.26 no.6
• /
• pp.175-181
• /
• 2022

The condition of infrastructure deteriorates as the service life increases. Since most infrastructure in South Korea were intensively built during the period of economic growth, the proportion of outdated infrastructure is rapidly increasing now. Aging of such infrastructure can lead to safety accidents and even human casualties. To prevent these issues in advance, periodic and accurate inspection is essential. For this reason, the need for research to detect various types of damage using computer vision and deep learning is increasingly required in the field of remotely controlled or autonomous inspection. To this end, this study proposed a neural network structure that can detect concrete damage by classifying it into three types. In particular, the proposed neural network can detect them more accurately through a hierarchical learning technique. This neural network was trained with 2,026 damage images and tested with 508 damage images. As a result, we completed an algorithm with average mean intersection over union of 67.04% and F1 score of 52.65%. It is expected that the proposed damage detection algorithm could apply to accurate facility condition diagnosis in the near future.

• Archives of Plastic Surgery
• /
• v.49 no.2
• /
• pp.195-199
• /
• 2022

Nasolacrimal duct (NLD) damage is associated in the majority of type II and III naso-orbito-ethmoid (NOE) fractures. Our study aims to investigate the efficacy and safety of prophylactic NLD intubation in the setting of facial fractures, by comparing incidence of postoperative epiphora and wound infection. A retrospective matched control study was conducted on all patients with surgically treated facial fractures from 2008 to 2013 (n=280) (IRB ref number: DSRB 2013/01198). Patients with the following fracture types were included: NOE (n=16), frontal sinus (n=2), Le Fort II/III (n=8), and > 1 type (n=48). All patients in this study were included with the intention to treat. The study group comprised patients who were intubated, while the control group patients were not intubated. Each group had 37 patients matched for age, gender, fracture type, and injury type. A single oculoplastic surgeon skilled in lacrimal surgery performed the procedure for all intubated patients. Patients with more severe and complex facial fractures were intubated with bicanalicular Crawford stents. Postoperative epiphora and infective complications (both facial wound and dacryocystitis) were assessed at 1, 3, 6, and 12 months. There was no significant difference in incidence of either postoperative epiphora (p=0.152) or wound infection (p=0.556) comparing both groups. Reduced incidence of postoperative epiphora in the study group is statistically not significant and does not support the need for prophylactic intubation. If radiographic evidence of NLD disruption or regurgitation seen on syringing on the NLD intraoperatively is present, intubation is safe and efficacious only if performed by an expert.

• The Journal of the Korea Contents Association
• /
• v.22 no.2
• /
• pp.125-134
• /
• 2022

Due to the development of smartphone technology, as of 2020, 91.9% of people use the Internet[1] to frequently acquire information through websites and mobile apps. As the number of homepages in charge of providing information is increasing every year, the number of applications for web vulnerability diagnosis, which diagnoses the safety of homepages, is also increasing. In the existing web vulnerability check, the number of diagnostic personnel should increase in proportion to the number of homepages that need diagnosis because the diagnosticians manually test the homepages for vulnerabilities. In reality, however, there is a limit to securing a web vulnerability diagnosis manpower, and if the number of diagnosis manpower is increased, a lot of costs are incurred. To solve these problems, an automatic diagnosis tool is used to replace a part of the manual diagnosis. This paper explores a new method to expand the current automatic diagnosis range. In other words, automatic diagnosis possible items were derived by analyzing the impact of web vulnerability diagnosis items. Furthermore, automatic diagnosis identified possible items through comparative analysis of diagnosis results by performing manual and automatic diagnosis on the website in operation. In addition, it is possible to replace manual diagnosis for possible items, but not all vulnerability items, through the improvement of automatic diagnosis tools. This paper will explore some suggestions that can help improve plans to support and implement automatic diagnosis. Through this, it will be possible to contribute to the creation of a safe website operating environment by focusing on the parts that require precise diagnosis.