• KIEAE Journal
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• v.8 no.1
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• pp.87-92
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• 2008

Sheathing work used for excavation in a crowded downtown is generally a temporary strut method using H-piles and sheathing wall includes lagging, CIP, SCW or slurry wall. A temporary strut serving the support for sheathing wall acts to resist the earth pressure, but it shall be removed when installing the underground structure members. A traditional temporary strut might cause the stress imbalance of the sheathing wall when it is demolished, resulting in time extension and the risk of collapse. A traditional temporary strut method thus needs to be improved for schedule and cost reduction, risk mitigation and for preparation for potential civic complaint. A permanent strut method doesn't require installing and demolishing the temporary structure that will lead to reducing the time and cost and the structural risk during the demolition process. And given the girder, the part of the underground structure, serves the role of strut, it can secure the wider interval compared to the traditional method, which enables to secure the wider space for the convenience of excavation as well as enhance the constructability and efficient site management. The thesis was intended to study the composite girder designed to use the strut as permanent structure so as to reduce the excavation and floor height.

• Journal of Korean Academy of Nursing
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• v.35 no.7
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• pp.1420-1425
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• 2005

Purpose: We try to disclose how much the keywords of the papers from the Journal of the Korean Academy of Nursing coincide with MeSH terminologies and to understand the major subjects of the recent nursing research in Korea from keywords. Methods: Keywords of journals were extracted and compared with MeSH terms. The frequency of the appearance of each keyword was sorted by a descending order. Results: Coincidence rate of 1,235 keywords with MeSH terms was $51.6\%$. Out of them, depression, elderly, stress, self efficacy, quality of life, exercise, middle-aged women, and women appeared most frequently in descending order. Conclusion: Coincidence rate of the keywords with MeSH terms was at an acceptable level, however to improve it, the education of submitters and editorial board members are required, as well as the copy editor, to take a role in checking keywords. To infer the subjects of the research from keywords might well represent the recent topics of research work.

• Journal of Magnetics
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• v.14 no.1
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• pp.7-10
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• 2009

In this work, we studied the effects of Sn addition on the ordering temperature of FePt thin film. The coercivity of FePtSn film was about 1000 Oe greater than the coercivity of FePt film for an annealing temperature of $600^{\circ}C$. Therefore, Sn addition was effective in promoting the $L1_0$ ordering and in reducing the ordering temperature of the FePt film. From our X-ray diffraction results, we found that in the as-deposited film, the addition of Sn induced a lattice expansion in disordered FePt thin films. After the annealing process, the excess Sn diffuses out from the ordered FePt thin film because of the difference in the solid solubility of Sn between the disordered and ordered phases. The existence of precipitates of Sn from the FePt lattice was deduced by Curie temperature measurements of the FePt and FePtSn films. Therefore, the key role played by the addition of Sn to the FePt film can be explained by a reduction in the activation energy for the $L1_0$ order-disorder transformation of FePt which originates from the high internal stress in the disordered phase induced by the supersaturated Sn atoms.

• Transactions of Materials Processing
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• v.14 no.6 s.78
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• pp.527-532
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• 2005

Among the failure modes which can occur in tube hydroforming such as wrinkling, bursting or buckling, the bursting by local instability under excessive tensile stresses is irrecoverable phenomenon. Thus, the accurate prediction of bursting condition plays an important role in producing the successfully hydroformed part without any defects. As the classical forming limit criteria, strain-based forming limit diagram (FLD) has widely used to predict the failure in sheet metal forming. However, it is known that the FLD is extremely dependant on strain path throughout the forming process. Furthermore, The application of FLD to hydroforming process, where strain path is no longer linear throughout forming process, may lead to misunderstanding for fracture initiation. In this work, stress-based forming limit diagram (FLSD), which is strain path-independent and more general, was applied to prediction of forming limit in tube hydroforming. Combined with the analytical FLSD determined from plastic instability theory, finite element analyses were carried out to find out the state of stresses during hydroforming operation, and then FLSD is utilized as forming limit criterion. In addition, the approach is verified by a series of bulge tests in view of bursting pressure and shows a good agreement. Consequently, it is shown that the approach proposed in this paper will provide a feasible method to satisfy the increasing practical demands for judging the forming severity in hydroforming processes.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2005.05a
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• pp.92-96
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• 2005

Among the failure modes which can be occurred in tube hydroforming such as wrinkling, bursting or buckling, the bursting by local instability under excessive tensile stresses is irrecoverable phenomenon. Thus, the accurate prediction of bursting condition plays an important role in producing the successfully hydroformed part without any defects. As the classical forming limit criteria, strain-based forming limit diagram has widely used to predict the failure in sheet metal forming. However, it is known that the FLD is extremely dependant on strain path throughout the forming process. Furthermore, the path-dependent limitation of FLD makes the application to hydroforming process, where strain path is no longer linear throughout forming process, more careful. In this work, stress-based forming limit diagram (FLSD), which is strain path-independent and more general, was applied to prediction of forming limit in tube hydroforming. Combined with the analytical FLSD determined from plastic instability theory, finite element analyses were carried out to find out Ihe state of stresses during hydroforming operation, and then FLSD is utilized as forming limit criterion. In addition, the approach is verified with a series of bulge tests in view of bursting pressure and shows a good agreement. Consequently, it is shown that the approach proposed in this paper will provide a feasible method to satisfy the increasing practical demands for judging the farming severity in hydroforming processes.

• Computers and Concrete
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• v.25 no.4
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• pp.293-302
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• 2020

Connections play a significant role in strength of structures against earthquake-induced loads. According to the post-seismic reports, connection failure is a cause of overall failure in reinforced concrete (RC) structures. Connection failure results in a sudden increase in inter-story drift, followed by early and progressive failure across the entire structure. This article investigated the cyclic performance and behavioral improvement of shape-memory alloy-based connections (SMA-based connections). The novelty of the present work is focused on the effect of shape memory alloy bars is damage reduction, strain recoverability, and cracking distribution of the stated material in RC moment frames under seismic loads using 3D nonlinear static analyses. The present numerical study was verified using two experimental connections. Then, the performance of connections was studied using 14 models with different reinforcement details on a scale of 3:4. The response parameters under study included moment-rotation, secant stiffness, energy dissipation, strain of bar, and moment-curvature of the connection. The connections were simulated using LS-DYNA environment. The models with longitudinal SMA-based bars, as the main bars, could eliminate residual plastic rotations and thus reduce the demand for post-earthquake structural repairs. The flag-shaped stress-strain curve of SMA-based materials resulted in a very slight residual drift in such connections.

• Journal of Ginseng Research
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• v.46 no.2
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• pp.206-213
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• 2022

Ginsenoside Rb2 is an active protopanaxadiol-type saponin, widely existing in the stem and leave of ginseng. Rb2 has recently been the focus of studies for pharmaceutical properties. This paper provides an overview of the preclinical and clinical pharmacokinetics for Rb2, which exhibit poor absorption, rapid tissue distribution and slow excretion through urine. Pharmacological studies indicate a beneficial role of Rb2 in the prevention and treatment of diabetes, obesity, tumor, photoaging, virus infection and cardiovascular problems. The underlying mechanism is involved in an inhibition of oxidative stress, ROS generation, inflammation and apoptosis via regulation of various cellular signaling pathways and molecules, including AKT/SHP, MAPK, EGFR/SOX2, TGF-β1/Smad, SIRT1, GPR120/AMPK/HO-1 and NF-κB. This work would provide a new insight into the understanding and application of Rb2. However, its therapeutic effects have not been clinically evaluated. Further studies should be aimed at the clinical treatment of Rb2.

• Journal of Korean society of Dental Hygiene
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• v.22 no.4
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• pp.259-272
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• 2022

Objectives: To identify the factors influencing the turnover intention of registered South Korean dental hygienists and analyze the effect sizes. Methods: Overall, 54 studies based on criteria of PICO from 1 January 2000 to 11 January 2022 were extracted. The factors related to turnover intention were applied to the ecological system theory and categorized. Subsequently, the effect size of the correlations was comprehensively meta-analyzed by dividing it into protective and risk factors depending on the negative or positive correlation direction. Results: For the overall effect size, the protective factor (ES_r=-0.458) was higher than the risk factor (ES_r=0.352). In the protective factors, organizational commitment and perceived organizational support belonging to the microsystem yielded the largest effect size. Furthermore, as for risk factors, burnout, job stress, work harassment, role conflict, and emotional labor belonging to the microsystem showed a moderate effect size. Conclusions: Factors belonging to the microsystem demonstrated a large effect size in both protection and risk factors for dental hygienists' turnover intention. Additionally, the factor showing the largest effect size was protective factor categorized into a microsystem.

• Korean Medical Education Review
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• v.25 no.1
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• pp.3-16
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• 2023

Unlike in the past, standards for the quantity and quality of work expected from medical school faculty are continuously rising, causing changes and stress in various areas. This highlights the need for career development among medical school faculty for professional, personal, organizational, and societal reasons. The role of medical school faculty has become more diverse, leading to an increase in the types and levels of competencies required. Medical schools must support their faculty members with diverse identities in fully utilizing their capabilities to achieve the institution's mission. Furthermore, societal changes suggest that career development for medical school faculty will become even more crucial in the future. To achieve this, both individuals and organizations must make efforts and play appropriate roles. For this purpose, medical schools use a combination of promotion and tenure evaluations and faculty development programs, while individual faculty members follow a career path within the medical school environment. Medical school faculty must be able to meet the evolving demands at each stage of their careers. It is important for professors, who engage in career development, to have a clear sense of their identity and values, and to prioritize their career goals. Medical schools should also ensure that the implicit messages they convey align with the organization's explicit values. Finally, proactively preparing for future changes in society and generations is essential from a long-term perspective.

• Safety and Health at Work
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• v.13 no.4
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• pp.448-455
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• 2022

Background: While the organizational factors that account for firefighters' burnout have been extensively explored, the individual factors related to how they regulate interpersonal conflicts and emotions remain to be investigated. Previous research has demonstrated the association between emotional intelligence and conflict management styles and burnout, but no study has looked at the interrelationships among these factors in high-risk sectors. The present exploratory study aimed to fill this research gap by investigating the relationships between conflict management style, emotional intelligence and burnout in a sample of firefighters. Methods: A cross-sectional study was conducted with 240 French firefighters. Measures comprised validated scales of conflict management styles, emotional intelligence and burnout. Results: Results showed that the integrating conflict style reduced burnout. They also revealed the effects of emotion regulation on burnout, whereby the awareness and management of one's own emotions reduced burnout. Moreover, awareness of one's own emotions moderated the relationship between integrating conflict resolution style and burnout, whereby the effect of integrating style on reduced burnout was higher when awareness of one's own emotions was high. Conclusion: These results reveal that strategies used by firefighters to regulate their emotions in order to meet the emotional demands specific to their job are important for reducing the emotional exhaustion component of burnout. Training programs for conflict and emotion management are needed to preserve the mental health of firefighters and ensure the safety of interventions.