• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.6B
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• pp.641-649
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• 2006

The behavior of a three-dimensional pure rectangular water jet with aspect ratio of 10 was experimentally investigated based on the results of the mean velocity field obtained by PIV. The saddle back distribution was observed in the lateral distribution along the major axis. The theoretical centerline velocity equation derived from the point source concept using the spreading rate for the axisymmetric jet was in good agreement with the measured centerline velocity and gave the division of the potential core region, two-dimensional region, and axisymmetric region. The range of the two-dimensional region divided by the criterion of the theoretical centerline velocity decay for the aspect ratio of 10 was observed to be smaller than that of the transition region. The applicability of the two-dimensional model to the behavior of the rectangular jet with low aspect ratio or the wastewater discharged from a multiport diffuser in the deep water of real ocean may result in significant error in the transition and axisymmetric regions after the two-dimensional region. In the two-dimensional region, the Gaussian constant tended to be conserved, and the spreading rate slightly decreased at the end of the two-dimensional region. The normalized turbulent intensity along the centerline of the jet initially abruptly increased and showed relatively higher intensity for higher Reynolds number.

• 한국노년학
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• v.31 no.4
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• pp.1067-1081
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• 2011

This study aimed to compare job stress and job satisfaction of long-term care staffs caring for demented seniors with rating 3 and physically disabled seniors with rating 1. Survey was conducted upon 212 long-term care staffs in long-term care institutions in Ejungboo, Goyang, and Paju. There were, first of all, statistically significant differences between those groups in the level of overall stress, stress related to service subjects, and stress in service procedures. Regression analyses, secondly, showed that the relationship between job stress and job satisfaction was statistically significant only for long-term care staffs for demented seniors with rating 3. The results suggest that it is necessary to lower the level of stress especially for the staffs caring for demented seniors with rating 3. Furthermore, we need to consider the stress, that the staffs feels in the process of caring for long-term care service beneficiaries, as a important variable for intervention programs to reduce the level of stress among long-term care staffs.

• Korean Journal of General Education
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• v.4 no.1
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• pp.237-254
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• 2010

For years, poor research and working conditions in the field of science and engineering in Korea led to the migration of gifted students to seek a better academic environment. The primary reason for such a phenomenon is the lack of a coherent education system for gifted students. With the support from the Ministry of Education, Science and Technology and the Korea Foundation for the Advancement of Science & Creativity, Hanyang University launched an exploring project to introduce an Honors Program, aiming to provide specialized and systematic learning opportunities as well as supporting greater academic achievements for gifted students at university-level. Students admitted to this program were selected not by conventional standards but by competency-based selection process, assessed through an in-depth interview. The specific goal of this program is to prepare gifted and talented students not only for an academic pioneer with the highest caliber in the field of science, but also for a global leader equipped with a creative view as well as integrity and a convergent mind. Distinctive features of this program include emphasis on fundamental science and consilience, problem solving skills, first-hand education, interpersonal skills, and global communication skills as well as individualization of the learning experience, among many others. This paper provides a short glimpse of the focus and methodology Honors Program in Hanyang University offers.

• Journal of the Korean Society of International Agriculture
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• v.23 no.5
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• pp.570-577
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• 2011

We developed insect-resistant GM rice(Bt transgenic rice) by inserting the mCry1Ac1 a modified gene from the soil bacterium, Bacillus thuringiensis. The Bt transgenic rice expressing the Bttoxin mCry1Ac1 was tested for the effects on survival of Misgurnus anguillicaudatus and Cyprinus carpio, commonly used as a model organism in ecotoxicological studies. M. anguillicaudatus and C. carpio fed 100% ground rice in suspension, using either Bt rice or non-GM counterpart rice(Nakdong). The Bt rice used for the test were confirmed to have the mCry1Ac1 gene expression by the immuno-strip and ELISA analysis. Feeding test showed that no significant differences in cumulative immobility and abnormal response of M. anguillicaudatus and C. carpio fed on between Bt rice and non-GM counterpart rice. The 96hr-LC₅₀ values showed no difference between Bt rice(>1,000mg/L) and non-GM rice(>1,000mg/L). We concluded that there was no significant difference in toxicity for non-target organisms(M. anguillicaudatus and C. carpio) between Bt rice and non-GM counterparts.

• Korean Journal of Culture and Social Issue
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• v.18 no.1
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• pp.111-125
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• 2012

The total fertility rate of our nation has been in the world's lowest level with constant falling since it reached an all-time low in 1983. The increase in economic participation of women, difficulties to balance work and family life, and traditional gender role and family norms in our society have been blamed for causing low birth rates. In addition, the current economic recession and increased polarization of wealth make it more difficult for working families to balance work and family life, resulting in lowering fertility rates. The Korean government has recently prepared the second five-year basic plan(2011-2015) to deal with low fertility and population ageing. The basic plan aims at providing support for working families in balancing work and family life and helping people ease the burden of marriage, childbirth, and raising their children. The work-family balance policies based on gender equality will do much to increase fertility rates in the future. In this context, this study examined current status and problems of balancing work and family life in our society, the Korean government and corporate policies for work-family balance, and the effects of policies on childbirth. Suggestions for future directions are presented.

• Korean Journal of Culture and Social Issue
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• v.16 no.4
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• pp.423-445
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• 2010

Previous research have demonstrated that the external factors (ex., money, appearance) are more influential in Easterners' self-views and conditions for happiness than those of Westerners'. Based on these results, the current study examined whether 1) children and adolescents acquired these tendency as they grew up and 2) this tendency had relevance with social comparison. Total 954 students (260 elementary, 216 middle school, 260 high school and 218 college students) participated in the study. The results showed that elementary and middle school students regarded the internal factors (ex., thinking, feeling) as more important. But high school students considered the external factors as more important, and there was no difference in college students. Also, the results revealed that elementary and middle school students regarded the harmony of family and peace of mind as more important conditions for happiness. These results contrasted with preference for better educational backgrounds, better occupation, and money in high school and college students. In addition, age and social comparison tendency had positive relation with external self-concepts and negative relation with self-esteem. Especially, high school students showed strongest external self-concepts and social comparison tendency among four age groups. They also showed strongest preference for external conditions for happiness, but their self-esteem was the lowest. This might reflect fierce competition for college education in Korea, and the results of the current study have demonstrated that adolescents developed a tendency to prefer external factors to internal factors as they grew up in a competitive environment.

• Journal of Internet Computing and Services
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• v.24 no.6
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• pp.137-144
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• 2023

Cyberattack technology is evolving to an unpredictable degree, and it is a situation that can happen 'at any time' rather than 'someday'. Infrastructure that is becoming hyper-connected and global due to cloud computing and the Internet of Things is an environment where cyberattacks can be more damaging than ever, and cyberattacks are still ongoing. Even if damage occurs due to external influences such as cyberattacks or natural disasters, intelligent self-recovery must evolve from a cyber resilience perspective to minimize downtime of cyber assets (OS, WEB, WAS, DB). In this paper, we propose an intelligent self-recovery technology to ensure sustainable cyber resilience when cyber assets fail to function properly due to a cyberattack. The original and updated history of cyber assets is managed in real-time using timeslot design and snapshot backup technology. It is necessary to secure technology that can automatically detect damage situations in conjunction with a commercialized file integrity monitoring program and minimize downtime of cyber assets by analyzing the correlation of backup data to damaged files on an intelligent basis to self-recover to an optimal state. In the future, we plan to research a pilot system that applies the unique functions of self-recovery technology and an operating model that can learn and analyze self-recovery strategies appropriate for cyber assets in damaged states.

• Journal of Internet Computing and Services
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• v.24 no.6
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• pp.171-180
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• 2023

Hydrogen energy technology is gaining importance in the era of the Fourth Industrial Revolution, offering military advantages when applied to military vehicles due to its characteristics such as reduced greenhouse gas emissions, noise, and low vibration. Korea's military has initiated the Army Tiger 4.0 plan, focusing on hydrogen application, downsizing, and AI-based smart features. The Ministry of National Defense plans to collaborate with the Ministry of Environment to expand hydrogen charging stations nationwide, anticipating increased deployment of military hydrogen vehicles. However, considering the Jet Fire and VCE(Vapor Cloud Explosion) nature of hydrogen, ensuring safety during installation is crucial. Current military guidelines specify a minimum safety distance of 2m from adjacent buildings for charging stations. Scientific methods have been employed to quantitatively assess the accident damage range of hydrogen, proposing a minimum safety distance beyond the affected area.

• Korean Journal of Microbiology
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• v.40 no.2
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• pp.147-153
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• 2004

Protein modification by N-acetyl-${\beta}$-D-glucosamine (O-G1cNAc) on the hydroxyl groups of Ser or Thr ubiq-uitously occurs in eukaryotic cells and is involved in many cellular phenomena. The level of O-G1cNAc-mod-ified protein is regulated by OGT and O-GlcNAcase enzymes. We have tried to produce recombinant O-GlcNAcase in E. coli as an effort to establish in vitro screening system for modulators of O-GlcNAcase. The culture conditions for improvement of O-GlcNAcase productivity, were as follows: induction temperature, $30^{\circ}C$; the concentration of L-arabinose, 0.02% and induction time, 5 hr. Under these culture conditions, E. coli cells containing O-GlcNAcase gene had no enzyme activity until up to 3 hr culture. However, O-GlcNAcase activity dramatically increased from 3 to 5 hr culture. It almost maintained the same level after 5 hr culture. Western blot analysis verified the amount of expressed O-GlcNAcase increased with culture time, being con-sistent with activity data. The optimal reaction condition determined in this study was as follows: protein quan-tity, $5{\mu}g$; reaction time, 30 min; reaction temperature, $45^{\circ}C$; substrate concentration, 2 mM; reaction pH, 6.5. Methanol had little effect on O-GlcNAcase activity and 90% of activity were retained at 10%. Only 15% resid-ual activity were detected at 5% of chloroform.

• Tunnel and Underground Space
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• v.33 no.6
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• pp.435-444
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• 2023

In the licensing application for the deep geological disposal system of high-level radioactive waste in Finland, the disposal tunnel backfilling has been changed from the block/pellet (for the construction) to the granular type (for the operation). Accordingly, for establishing the design concept for backfilling, it is necessary to examine applicability to the domestic facility through analyzing problems of the existing method and improvements in the alternative design. In this paper, we first reviewed the principal studies conducted for changing the backfill method in the licensing process of the Finnish facility, and identified the expected problems in applying the block/pellet backfill method. In addition, we derived the evaluation factors to be considered in terms of technical and operational aspects for the backfilling solution, and then conducted a comparative analysis for two types of backfill methods. This analysis confirmed the overall superiority of the design change. It is expected that these results could be utilized as the technical basis for deriving the optimum design plan in development process of the Korean-specific deep disposal facility. However, applicability should be reviewed in advance based on the latest technical data for the detailed evaluation factors that must be considered for selecting the backfilling method.