• Journal of Ocean Engineering and Technology
• /
• v.31 no.4
• /
• pp.288-298
• /
• 2017

A study of the damage evolution laws for ductile materials was carried out to predict the ductile fracture behavior of a marine structural steel (EH36). We conducted proportional and non-proportional stress tests in the experiments. The existing 3-D fracture strain surface was newly calibrated using two fracture parameters: the average stress triaxiality and average normalized load angle taken from the proportional tests. Linear and non-linear damage evolution models were taken into account in this study. A damage exponent of 3.0 for the non-linear damage model was determined based on a simple optimization technique, for which proportional and non-proportional stress tests were simultaneously used. We verified the validity of the three fracture models: the newly calibrated fracture strain model, linear damage evolution model, and non-linear damage evolution model for the tensile tests of the asymmetric notch specimens. Because the stress evolution pattern for the verification tests remained at mode I in terms of the linear elastic fracture mechanics, the three models did not show significant differences in their fracture initiation predictions.

• Journal of Aerospace System Engineering
• /
• v.13 no.4
• /
• pp.66-73
• /
• 2019

The objective of this study was to evaluate the structural safety of the basic design for the linear actuator for the flap control of aircrafts. The kinetic behavior of the linear actuator was determined using the multi-body dynamics (MBD) analysis, and the contact force was calculated to be used as input data for the structural analysis based on the finite element analysis. In the structural analysis, the thermal and static behaviors of the linear actuator satisfying the designed velocity were examined, and the structural safety of the linear actuator evaluated. Moreover, the dynamic behaviors of the key components of the linear actuator were investigated by the modal analysis. The actuation rod linearly moved with about 5 mm/s when the motor operated at 225 rpm and the maximum contact force of 32.83 N occurred between two driving gears. Meanwhile, the structural analysis revealed that the maximum thermal and static stresses were 1.57% and 78% of the yield strength of steel, respectively, and they were in a safe range of the structure. In addition, the linear actuator for the basic design is stable to the resonance by avoiding the natural frequencies of the components.

• Structural Engineering and Mechanics
• /
• v.61 no.1
• /
• pp.125-142
• /
• 2017

Extensive research work has been performed on shear strengthening of reinforced concrete (RC) beams retrofitted with externally bonded carbon fiber reinforced polymer (CFRP) in form of strips. However, most of this research work is experimental and very scarce studies are available on numerical modelling of such beams due to truly challenging nature of modelling concrete shear cracking and interfacial interaction between components of such beams. This paper presents an appropriate model for RC beam and to simulate its cracking without numerical computational difficulties, convergence and solution degradation problems. Modelling of steel and CFRP and their interfacial interaction with concrete are discussed. Finally, commercially available non-linear finite element software ABAQUS is used to validate the developed finite element model with key tests performed on full scale T-beams with and without CFRP retrofitting, taken from previous extensive research work. The modelling parameters for bonding behavior of CFRP with special anchors are also proposed. The results presented in this research work illustrate that appropriate modelling of bond behavior of all the three types of interfaces is important in order to correctly simulate the shear behavior of RC beams strengthened with CFRP.

• Journal of Korean Academy of Rural Health Nursing
• /
• v.15 no.2
• /
• pp.41-48
• /
• 2020

Purpose: This study was a descriptive study to identify the factors affecting the dementia prevention behavior of elders in rural communities. Methods: The participants in this study were 125 elders aged 60 or older who lived in Eup or Myeon areas of P city. For data analysis, SPSS/WIN 22.0 was used to perform descriptive statistics, t-test, ANOVA, Pearson correlation, and linear multiple regression and mediated effects. Results: Scores for dementia recognition, dementia attitude and dementia prevention behavior averaged 5.6±2.50 points in the 0~11 range, 38.8±4.59 in 14~56 and 20.2±3.59 in 10~30 respectively. Dementia recognition (a), dementia attitude (b), dementia prevention behavior (c) and the number of chronic diseases of the elders (d) were positively or negatively correlated with each other (rab=.29, p<.01; rbc=.26, p<.01; rac=.36, p<.01; rad=-.29, p<.01; rcd=.19, p<.05). Factors affecting dementia prevention behavior were dementia recognition, dementia attitude, and degree of dementia interest. When the number of chronic diseases affects dementia prevention behavior, dementia recognition has a mediating effect. Conclusion: In order to prevent dementia among elders in rural areas, appropriate management of chronic diseases and provision of appropriate dementia-related education and information to enhance dementia recognition should be provided.

• Nuclear Engineering and Technology
• /
• v.54 no.4
• /
• pp.1382-1393
• /
• 2022

This paper investigates the seismic behavior of an electrical cabinet considering the influence of equipment-anchor-interaction (EAI) that is generally not taken into consideration in a decoupled analysis. The hysteresis behavior of an anchor bolt in concrete was thereby considered to highlight this interaction effect. To this end, the experimental behavior of an anchor bolt under reversed cyclic loading was taken from the recently developed literature, and a numerical model for the anchor hysteresis was developed using the component approach. The hysteresis properties were then used to calibrate the multi-linear link element that is implemented as a boundary condition for the cabinet incorporating the EAI. To highlight this EAI further, the nonlinear time history analysis was performed for a cabinet considering the hysteresis behavior comparative to a fixed boundary condition. Additionally, the influence on the seismic fragility was evaluated for the operational and structural condition of the cabinet. The numerical analysis considering the anchor hysteresis manifests that the in-cabinet response spectra (ICRS) are significantly amplified with the corresponding reduction in the seismic capacity of 25% and 15% for an operational and structural safety condition under the selected protocols. Considering the fixed boundary condition over a realistic hysteresis behavior of the anchor bolt is more likely to overestimate the seismic capacity of the cabinet in a seismic qualification procedure.

• The Journal of Asian Finance, Economics and Business
• /
• v.9 no.1
• /
• pp.423-435
• /
• 2022

Sharing culture brings many benefits to enterprises, creating initiative and efficiency in the work performance of managers and employees. The study aims to test the correlation between Sharing culture, opportunistic behavior, and effectiveness of employee management in enterprises in Vietnam. There is the implementation of a quantitative research method, through analysis of linear structural model SEM, with survey data including 601 samples of employees at enterprises. Research results show that sharing culture has a direct and negative impact on opportunistic behavior, positively on the effectiveness of employee management in enterprises. In these correlations, the employee's Trust and Organization commitment act as mediators. At the same time, opportunistic behavior has also been shown to play a mediating role in the relationship between the impact of Sharing culture on the effectiveness of employee management. Based on those results, the study suggested several recommendations to improve the effectiveness of employee management. The findings of this study have shown the importance of sharing culture and its direct and indirect correlation with opportunistic behavior and the effectiveness of employee management. These are meaningful contributions in both theory and practice of the research, and they will be the important basis for further research.

• Korean Journal of Occupational Health Nursing
• /
• v.33 no.1
• /
• pp.36-46
• /
• 2024

Purpose: This study aimed to investigate compassion competence and its mediating effects on the relationship between attitudes toward dementia and care behavior among caregivers of older adults with dementia in nursing homes. Methods: 211 participants were recruited for this cross-sectional study. Data were collected from February 1st to May 24th, 2023, through a structured questionnaire and analyzed using multiple linear regression analysis and the bootstrapping method. Results: The mean score for care behavior was 3.67±0.97 (range 1~5). Caring behaviors were significantly associated with attitudes toward dementia (r=.76, p<.001) and compassion competence (r=.75, p<.001). Using Baron and Kenny's approach and PROCESS Macro model 4, care behavior was directly affected by dementia attitude (β=.76, p<.001). Compassion competence (β=.66, p<.001) was directly affected by dementia attitude. The partial mediating effects of compassion competence (β=.47, p<.001, 95% confidence interval 0.10~0.23) on the impact of dementia attitude on care behavior was confirmed. Conclusion: The results suggest that compassion competence should be considered when developing nursing interventions to enhance dementia-related attitudes and improve care behavior among caregivers of older adults with dementia.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2009.05a
• /
• pp.567-568
• /
• 2009

The CAMUS 2000-1 experimental program were performed in France to investigate of the 1/3-scaled reinforced concrete bearing walls behavior on the shaking table under biaxial earthquake loading. The nonlinear 3D finite element analysis of push over test and linear dynamic analysis under biaxial earthquake loading are investigated with the concrete damaged plasticity model using ABAQUS.

• 제어로봇시스템학회:학술대회논문집
• /
• 1986.10a
• /
• pp.256-261
• /
• 1986

The sensitiveness of the stability characteristics of the aircraft with respect to changes in the stability parameters as predicted by the linear analysis is applied for the two aerodynamic models proposed. The results give the detailed information for an aircraft dynamic behavior especially at complicated flight envelope.

• Proceedings of the KWS Conference
• /
• 2002.05a
• /
• pp.139-142
• /
• 2002