• Smart Structures and Systems
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• v.23 no.3
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• pp.227-242
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• 2019

Seismic isolation systems employ structural control that protect both buildings and vibration-sensitive contents from destructive effects of earthquakes. Structural control is divided into three main groups: passive, active, and semi-active. Among them, semi-active isolation systems, which can reduce floor displacements and accelerations concurrently, has gained importance in recent years since they don't require large power or pose stability problems like active ones. However, their seismic performance may vary depending on the variations that may be observed in the mechanical properties of semi-active devices and/or seismic isolators. Uncertainties relating to isolators can arise from variations in geometry, boundary conditions, material behavior, or temperature, or aging whereas those relating to semi-active control devices can be due to thermal changes, inefficiencies in calibrations, manufacturing errors, etc. For a more realistic evaluation of the seismic behavior of semi-active isolated buildings, such uncertainties must be taken into account. Here, the probabilistic behavior of semi-active isolated buildings under historical pulse-like near-fault earthquakes is evaluated in terms of their performance in preserving structural integrity and protecting vibration-sensitive contents considering aforementioned uncertainties via Monte-Carlo simulations of 3-story and 9-story semi-active isolated benchmark buildings. The results are presented in the form of fragility curves and probability of failure profiles.

• Journal of East-West Nursing Research
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• v.24 no.2
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• pp.101-109
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• 2018

Purpose: The purpose of this study was to construct and test a structural equation model of health behavior compliance among patients with percutaneous coronary intervention based on self-determination theory. Methods: A total of 227 participants who received follow-up care after percutaneous coronary intervention were recruited. A structured questionnaire was used to assess health providers' autonomous support, basic psychological needs, autonomous motivation, controlled motivation, type D personality, and health behavior compliance. Collected data were analyzed using SPSS 21.0 and AMOS 21.0 program. Results: The final hypothetical model showed a good fitness with data: GFI=.94, RMSEA=.07, CFI=.96, NFI=.92, TLI=.94. The results revealed that autonomous support of health care providers, basic psychological needs, and autonomous motivation, and D-type personality accounted for 51.8% of health behavior compliance. Conclusion: The findings of this study indicate that enhanced autonomous support of health care providers is essential to promote patients' basic psychological needs and autonomous motivation. This leads to maximized compliance to the health behaviors among patients who underwent percutaneous coronary intervention. We recommend that health care institutions establish various measures to foster the special environments in which health care providers can actively provide and utilize autonomous support for their patients.

• Journal of Korean Academy of Nursing
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• v.32 no.1
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• pp.62-76
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• 2002

This study was designed to construct a structural model for health promoting behavior of patients with chronic disease. The hypothetical model was developed based on the literature review and Pender's health promotion model. Method: Data was collected by questionnaires from 1748 patients with chronic disease in General Hospital from December 1999 to July 2000 in Seoul. The disease of subject were cardiac disease included hypertension peptic ulcer, pulmonary disease included COPD and asthma, DM, and chronic kidney disease. Data analysis was done with SAS 6.12 for descriptive statistics and PC-LISREL 8.13 Program for Covariance structural analysis. Results: 1. The fit of the hypothetical model to the data was moderate, it was modified by excluding 4 path and including free parameters to it. The modified model with path showed a good fitness to the empirical data (χ2=591.83, p<.0001, GFI=0.97, AGFI= 0.94, NNFI=0.95, RMSR=0.01, RMSEA=0.05). 2. The perceived benefits, perceived barriers, self-efficacy, self- esteem, and the plan for action were found to have significant direct effect on health promoting behavior of chronic disease. 3. The health concept, health perception, emotional state, social support were found to have indirect effects on health promoting behavior of chronic disease. Conclusion: The derived model in this study is considered appropriate in explaining and predicting health promoting behavior of patients with chronic disease. Therefore, it can effectively be used as a reference model for further studies and suggested implication in nursing practice.

• Journal of Korean Society of Steel Construction
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• v.21 no.3
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• pp.277-287
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• 2009

The objective of this study was to experimentally investigate the structural behavior of steel plate concrete walls with vertical ribs (SSC walls), to compare the experimental results with the currently applied evaluation equations, and to obtain information that would be useful in the development of design equations for SSC walls. SSC test specimens that were subjected to in plane shear forces and bending moments were fabricated and tested. The experimental results show that the effect of vertical ribs on the structural behavior of SSC walls may be neglected, and that the confinement effect of concrete on the steel plates on both sides of the walls was negligible. The comparison of the experimental results with the evaluation equations showed that the structural behavior of SSC walls under shear control is close to that of the evaluation equations, but that the behavior of SSC walls under larger bending moments is not very close to that of the evaluation equations. The current evaluation equations for USC walls may be applied to the design of SSC walls because the structural walls of nuclear power plants are not subjected to large in plane bending moments.

• Journal of the Korean Institute of Landscape Architecture
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• v.25 no.4
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• pp.18-29
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• 1998

This study was carried out to test the theory of planned behavior in recreational choices behavior. Lotte World was chosen as study area, and college students were selected by nonprobability sampling for two waves of data collection. The first wave of data were collected one weeks into the spring semester : intention, attitude, subjective norm, and perceived behavioral control were measured. To collect the data of the second wave, the same resondents were asked their behavior, one week data of the second wave, the same respondents were asked their behavior , one week prior to the final examination : whether they visited the Lotte World or not. Polychoric correlation among variables were calculated by the PRELIS because behavior was nominal variable. Then, weighted least square method was utilized to calibrate structural equation model by the LISREL version 7.2. Structural link effect on intention among three determinants : the direct effect on intention was 0.421 and the indirect effect via intention on behavior was 0.145, respectively. However, its effect on behavior was insignificant because actual control over 'visiting of Lotte World' was relatively high. A few comments were sugested on data collection, and inclusion of new variables was discussed for the sufficiency f the theory of planned behavior.

• International Journal of High-Rise Buildings
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• v.1 no.1
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• pp.37-51
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• 2012

New generation of tall and complex buildings systems are now introduced that are reflective of the latest development in materials, design, sustainability, construction, and IT technologies. While the complexity in design is being overcome by the availability and advances in structural analysis tools and readily advanced software, the design of these buildings are still reliant on minimum code requirements that yet to be validated in full scale. The involvement of the author in the design and construction planning of Burj Khalifa since its inception until its completion prompted the author to conceptually develop an extensive survey and real-time structural health monitoring program to validate all the fundamental assumptions mad for the design and construction planning of the tower. The Burj Khalifa Project is the tallest structure ever built by man; the tower is 828 meters tall and comprises of 162 floors above grade and 3 basement levels. Early integration of aerodynamic shaping and wind engineering played a major role in the architectural massing and design of this multi-use tower, where mitigating and taming the dynamic wind effects was one of the most important design criteria established at the onset of the project design. Understanding the structural and foundation system behaviors of the tower are the key fundamental drivers for the development and execution of a state-of-the-art survey and structural health monitoring (SHM) programs. Therefore, the focus of this paper is to discuss the execution of the survey and real-time structural health monitoring programs to confirm the structural behavioral response of the tower during construction stage and during its service life; the monitoring programs included 1) monitoring the tower's foundation system, 2) monitoring the foundation settlement, 3) measuring the strains of the tower vertical elements, 4) measuring the wall and column vertical shortening due to elastic, shrinkage and creep effects, 5) measuring the lateral displacement of the tower under its own gravity loads (including asymmetrical effects) resulting from immediate elastic and long term creep effects, 6) measuring the building lateral movements and dynamic characteristic in real time during construction, 7) measuring the building displacements, accelerations, dynamic characteristics, and structural behavior in real time under building permanent conditions, 8) and monitoring the Pinnacle dynamic behavior and fatigue characteristics. This extensive SHM program has resulted in extensive insight into the structural response of the tower, allowed control the construction process, allowed for the evaluation of the structural response in effective and immediate manner and it allowed for immediate correlation between the measured and the predicted behavior. The survey and SHM programs developed for Burj Khalifa will with no doubt pioneer the use of new survey techniques and the execution of new SHM program concepts as part of the fundamental design of building structures. Moreover, this survey and SHM programs will be benchmarked as a model for the development of future generation of SHM programs for all critical and essential facilities, however, but with much improved devices and technologies, which are now being considered by the author for another tall and complex building development, that is presently under construction.

• Computational Structural Engineering
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• v.20 no.4
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• pp.19-25
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• 2007

• Computational Structural Engineering
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• v.28 no.2
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• pp.45-51
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• 2015

• Computational Structural Engineering
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• v.23 no.1
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• pp.41-48
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• 2010

• Computational Structural Engineering
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• v.17 no.4 s.66
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• pp.23-28
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• 2004