• Tunnel and Underground Space
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• v.28 no.1
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• pp.25-37
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• 2018

Burger's model was used to analyze creep characteristics of unconsolidated rock. Burger's model should determine four physical parameters from two pairs of data. In this study, physical parameters of Burger's model were determined by applying mathematical concept solution. Creep was accelerated for three years using the determined physical parameters of the Burger's model for unconsolidated rocks. As a result, the creep behavior showed a continuous deformation behavior without convergence. Therefore, in this mine, it is analyzed that the application of U-Beam is more appropriate than roofbolt in terms of stability.

• Journal of The Korean Association For Science Education
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• v.32 no.6
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• pp.1072-1086
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• 2012

Science, Technology, Engineering, and Mathematics (STEM) education in the U.S. has been identified as a significant national reform in K-16 education and curriculum in order to prepare students for the global economy of the 21st century. Korea has been facing very similar challenges to improve science, technology and mathematics education, in particular, the affective aspect of learning science and mathematics. Science, Technology, Engineering, Arts, and Mathematics (STEAM) education has become a crucial issue in Korean education system. The major purpose of this exploratory study is to inform the exemplary framework of STEAM education in the U.S. for Korea and to provide descriptive and analytical accounts on STEAM teaching and learning as an innovative integrated convergence education. This study integrates the outcomes of research papers on STEM education and recent literature. It employs content analysis methodology qualitatively by analyzing and synthesizing the findings, conclusions, discussions, and recommendations of accumulated research works related to STEM/STEAM education. This study will help gain a stronger sense of the STEAM framework and will guide to develop the educational programs for Korea.

• Journal of Digital Convergence
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• v.11 no.3
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• pp.279-284
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• 2013

Wireless access network section needs strong security which supports high data rate and mobility not to invade patient's privacy by exposing patient's sensitive biometric from automatic implantable device that is adapted to u-healthcare service. This paper builds test bed and performs assessment and measurement of security ability of WiMAX network to transmit and receive mobile patient's biometric by building WiMAX network in wireless access network not to expose paitne's biometirc at wireless access network section to the third person. Specially, this paper compares and assesses data security, MAC control message security, handover conection delay, and frame loss and bandwidth of ECDH at the layer of WiMAX security compliance, WiMAX MAC IPSec, and MAC.

• Fire Science and Engineering
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• v.27 no.2
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• pp.46-53
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• 2013

The architecture environment has changed. The corresponding design criteria should be changed. From July 27th, 2005 the Korea Standard of the fire door changed concerning the smoke resistance test which made the door gap structure more elaborate. However the National Fire Safety Codes are applied by the old data's of England. Which in case differs in the actual construction to the blue print, making the safety standard too excessive. Analyze the results and the phenomenon that occurs due to the difference between design and reality. The National Fire Safety Codes should be revised to leakage crack calculation is presented. Difference of the air flow for the smoke protection due to the stack effect analyzed. Living patterns and evacuation patterns of the apartment reflect and reasonable air flow measurement method are presented.

• Journal of the Korea Convergence Society
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• v.11 no.1
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• pp.337-347
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• 2020

The purpose of this study was to investigate the effects of strengths perspective group art therapy on the strength-related perspectives on the stress, depression and impulsivity of male middle school students who smoke. Data were collected from 15 middle school smokers from two middle schools in A city. Among them, 8 experimental groups and 7 other control groups were willing to participate in art therapy. The collected data were analyzed by nonparametric test considering the number of groups was 15. The Mann-Whitney U test and Wilcoxon signed ranks test were performed. As a result, the strength-focused group art therapy program showed stress (z = -2.521, p <.05), depression (z = -2.527, p <.05), impulse (z = -2.371, p < .05). Therefore, it can be found that strengths perspective group art therapy has a positive effect on the psychological well-being of smoking middle school students, and furthermore, it is necessary to study the deep emotional state of smoking middle school students.

• Journal of the Institute of Convergence Signal Processing
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• v.9 no.2
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• pp.141-145
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• 2008

When the current flows to parallel lines with different length, it is researched that the radiation is occured by the common-mode current radiates, and the small light weight antenna composed of dual elements by using the principle is proposed. However, there is a problem in production about this antenna because this liner antenna is structured by combining with wires. In this paper, we improved this liner antenna, and designed the plane antenna composed of dual elements with different length in the plane printed board to produce and to design easily. Furthermore, the antenna with the wide-band characteristic is also designed in the same board. The radiation pattern is similar to the dipole antenna on account of designing the triangular patch S, the notch and two tapers in patch S, the notch and two tapers in the antenna element. In result, it was able to design the antenna working wider band-width(the bandwidth ratio about 58%, $VSWR{\le}2$).

• Journal of Convergence for Information Technology
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• v.7 no.6
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• pp.45-52
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• 2017

The purpose of this study was to investigate the effects of husbands' help on postpartum depression and self-efficacy of mothers, to investigate what to fix of research design and to examine the feasibility of following experimental study. There was no significant difference in the general characteristics of two groups, which consisted 10 pairs of postpartum mothers and husbands, respectively, confirming the homogeneity of between groups. The prevalence of postpartum depression was 45% in the subjects who were measured at 1 week postpartum, and the average performance of the husbands' help in the experimental group was 3.2 out of 4 points. In the Mann-Whitney U Test, the husbands' help lowered the mean rank of postpartum depression in the experimental group(p<.001), and the mean rank of self-efficacy was higher than the control group, but there was no significant difference. In the process of this study, it was confirmed that, on the side of postpartum mothers of control group had burdens of responding to the questionnaire without the benefit of treatment so it is necessary to revise the design of following experimental study.

• Journal of Digital Convergence
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• v.17 no.9
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• pp.311-320
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• 2019

This study is a descriptive research designed to determine the effects of smartphone addiction on sleeping time and sleep deprivation among college students. For this purpose, the study made a questionnaire survey of 280 health science college students attending at C college located U Metropolitan city. Data collected from the survey were analyzed using SPSS 22.0 program. The findings of this study can be summarized as follows. there were correlations between smartphone addiction and students' sleep deprivation but weren't correlations between their smartphone addiction and sleeping time. furthermore college students' sleep deprivation was influenced by their smartphone addiction. Therefore, in order to induce sufficient sleep for physical and mental health, it is needed to reduce the smartphone addiction rate of college students. To do that, it is necessary to develop and provide interventive programs to eradicate unnecessary smartphone use.

• Journal of the Korea Convergence Society
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• v.13 no.4
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• pp.287-292
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• 2022

In this paper, the stochastic distribution of the springback amount is investigated for the stamping process of a U-channel shaped-product with ultra-high strength steel. Using the reliability-based design optimization technique (RBDO), stochastic distribution of process parameters is considered in the analysis including material properties and process variation. Quantification of the springback scatters is carried out with the statistical analysis method according to the material strength. It is found that the scattering amount of springback decreases while the amount of springback increases as the tensile strength of the blank material increases, which is investigated by analyzing the strain and stress distribution of the punch and die shoulder. It is noted that the proposed scheme is capable of predicting and responding to the unavoidable scattering of springback in the sheet metal forming process.

• Convergence Security Journal
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• v.23 no.2
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• pp.11-25
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• 2023

Since President Biden's inauguration, significant cyberattacks have occurred several times in the United States, and cybersecurity was emphasized as a national priority. The U.S. is advancing efforts to strengthen the cybersecurity both domestically and internationally, including with allies. In particular, the Biden administration announced the National Cybersecurity Strategy in March 2023. The National Cybersecurity Strategy is the top guideline of cybersecurity and is the foundation of other cybersecurity policies. And it includes public-privates as well as international policy directions, so it is expected to affect the international order. Meanwhile, In Korea, a new administration was launched in 2022, and the revision of the National Cybersecurity Strategy is necessary. In addition, cooperation between Korea and the U.S. has recently been strengthened, and cybersecurity is being treated as a key agenda in the cooperative relationship. In this paper, we examine the cyber security strategies of the Trump and Biden administration, and analyze how the strategies have changed, their characteristics and implications in qualitative and quantitative terms. And we derive the implications of these changes for Korea's cybersecurity policy.