• Ocean Systems Engineering
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• v.13 no.3
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• pp.287-312
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• 2023

The global performance of a 15 MW floating offshore wind turbine, a newly designed semisubmersible floating foundation with multiple heave plates by CNOOC, is investigated with two independent turbine-floater-mooring coupled dynamic analysis programs CHARM3D-FAST and OrcaFlex. The semisubmersible platform hosts IEA 15 MW reference wind turbine modulated for VolturnUS-S and hybrid type (chain-wire-chain with clumps) 3×2 mooring lines targeting the water depth of 100 m. The numerical free-decay simulation results are compared with physical experiments with 1:64 scaled model in 3D wave basin, from which appropriate drag coefficients for heave plates were estimated. The tuned numerical simulation tools were then used for the feasibility and global performance analysis of the FOWT considering the 50-yr-storm condition and maximum operational condition. The effect of tower flexibility was investigated by comparing tower-base fore-aft bending moment and nacelle translational accelerations. It is found that the tower-base bending moment and nacelle accelerations can be appreciably increased due to the tower flexibility.

• Earthquakes and Structures
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• v.14 no.1
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• pp.85-94
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• 2018

The paper focuses on the seismic responses of a hyperbolic cooling tower resting on soil foundation represented by the three-parameter Vlasov elastic soil model. The three-parameter soil model eliminates the necessity of field testing to determine soil parameters such as reaction modulus and shear parameter. These parameters are calculated using an iterative procedure depending on the soil surface vertical deformation profile in the model. The soil and tower system are modeled in SAP2000 structural analysis program using a computing tool coded in MATLAB. The tool provides a two-way data transfer between SAP2000 and MATLAB with the help of Open Application Programming Interface (OAPI) feature of SAP2000. The response spectrum analyses of the tower system with circular V-shaped supporting columns and annular raft foundation on elastic soil are conducted thanks to the coded tool. The shell and column forces and displacements are presented for different soil conditions and fixed raft base condition to investigate the effects of soil-structure interaction. Numerical results indicate that the flexibility of soil foundation leads to an increase in displacements but a decrease in shell membrane and column forces. Therefore, it can be stated that the consideration of soil-structure interaction in the seismic response analysis of the cooling tower system provides an economical design process.

• Journal of Convergence for Information Technology
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• v.11 no.10
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• pp.239-249
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• 2021

The purpose of this study is to verify the mediating effects of psychological flexibility on the relationship between emotional dissonance and mental health(depression, anxiety, somatic symptoms) in university administration staff. For this study, a sample of 191 university administration staff completed the questionnaires. The data was analyzed using the SPSS program and Sobel Test. The results of the analysis are as follows: 1. Most of the university administration staff had difficulties with emotional dissonance(52.36%), depression(47.12%), anxiety(58.12%), and somatic symptoms(62.83%). 2. The risk group of emotional dissonance had a significantly higher level of depression, anxiety and somatic symptoms compared with the normal group. 3. Emotional dissonance and psychological flexibility had a significant effect on depression, anxiety and somatic symptoms. 4. The mediating effects of psychological flexibility on the relationship between emotional dissonance and mental health(depression, anxiety, somatic symptoms) was verified. Finally, We suggested the need to intervene in emotional labor and mental health in university administration staff and psychological flexibility as an intervention and prevention method.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.43 no.4
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• pp.178-189
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• 2020

The purpose of this study was to analyze structural relationships with regard to the effect of customer integration, which is a type of integration in the supply chain, and market orientation of supply chain on the resulting change in the supply chain and management performance. The results of analysis in this study are as follows: First, customer integration and market orientation had a positive effect on reducing the flexibility and uncertainty of SCM. The decreased flexibility and uncertainty of SCM had a positive effect on non-financial performance, which also had a positive effect on financial performance. Second, customer integration and market orientation had a positive effect on financial and non-financial performance indirectly by decreasing the flexibility and uncertainty of SCM. Third, the effect of customer integration and uncertainty of SCM on the flexibility of SCM changed depending on the position in the supply chain; the effect was larger in the distribution group. The implications based on the analysis results are as follows: It is expected that the ability to deal with market changes in the overall supply chain is improved by laying the foundation for cooperation through establishing information infrastructure, including sharing information with trade partners and integrating systems, and implementing customer integration based on these achievements. It is also necessary to consider the business types and characteristics of individual companies in establishing information infrastructure.

• Journal of the Korean Society of Physical Medicine
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• v.16 no.2
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• pp.115-123
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• 2021

PURPOSE: This study aimed to investigate the benefits of thoracic manipulation and the trunk stability exercises on spine trunk flexibility and the pain index of chronic low back pain patients. METHODS: The study included 44 patients suffering from chronic low back pain. The participants were divided into two groups: the first group was assigned for trunk stability exercises (TSE), and the second group was randomly assigned TSE and thoracic manipulation at the same time (TSE+TM). Both groups carried out each assigned treatment thrice a week for 8 weeks. The study outcome was based on assessment of spine trunk flexibility and the pain index. Spine trunk flexibility was measured by spine flexion and extension through a range of motion and thoracic cage circumference. The pain index was measured using a visual analog scale (VAS). RESULTS: Spine flexion and extension range of motion showed a significant difference within each group and between the groups before and after the treatment. The measurement of the thoracic cage circumference also showed a notable difference within each group and between the groups before and after the treatment. There was no change in the pain index. CONCLUSION: These results indicate that thoracic manipulation with the trunk stability exercises is an efficient treatment for improving the spine trunk flexibility and soothing pain for chronic low back pain patients.

• Journal of the Korean Geotechnical Society
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• v.30 no.12
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• pp.41-49
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• 2014

The 3D numerical analysis is carried out to investigate the settlement behavior of flexible mat foundations subjected to vertical loads. Special attention is given to the improved analytical method (YS-MAT) that reflects the mat flexibility and soil spring coupling effect. The soil model captures the stiffness of the soil springs as well as the shear interaction between the soil springs. The proposed method has been validated by comparing the results with other numerical methods and a field measurement on mat foundation. Through comparative studies, the settlement of the proposed method was in relatively good agreement with those of a field measurement and other numerical methods. The results permit us to estimate the response of the mat foundation subjected to vertical loads that should be taken into account in the combination of mat flexibility and soil continuity characteristics.

• Journal of the Earthquake Engineering Society of Korea
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• v.6 no.6
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• pp.25-32
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• 2002

In the seismic designing of bridges, the pile foundation of bridge piers generally have been modeled to have a fixed end for its convenience and conservative designing. The fixed-end assumption, however, produces very conservative results in terms of the pier forces. Therefore, many other design methods are evolved to consider the flexibility of the pile foundation. In this study, the response spectrum analysis was performed for a bridge pier having a pile foundation. The shear force, moment, and displacement, which occurred at the pier column under an earthquake loading, were compared to analyze the effects of the modeling method, soil condition and the input earthquake response spectrum. In most cases, the fixed-end model gives larger design forces than flexible foundation models. However, when a long period earthquake is applied to the bridge pier on a soft clay foundation, it is found that the flexible foundation models give larger design forces than the fixed-end model. In the end, the reliability of several flexible foundation models was verified by comparing their results with those of a numerical analysis that considers the soil-structure interaction phenomenon in a rigorous manner.

• Journal of the Korean Geotechnical Society
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• v.22 no.4
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• pp.105-111
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• 2006

Earthquake strong motion recordings from two deeply embedded sites with instrumented structures and free-field accelerographs are used to evaluate variations between foundation-level and free-field ground motions. The foundation free-field ground motion variations are quantified in terms of frequency-dependent transmissibility function amplitude, ${\mid}H\mid$. Comparisons are then performed with an analytical model for the assumed conditions of a rigid base slab and a vertically propagating, coherent incident wave. The limiting assumptions of the model are not strictly satisfactory for actual structures, and the results of the analysis reflect not only incoherence effects, but also possible foundation flexibility and wave inclination effects. Nonetheless, the simple analytical model is in an acceptable agreement with the empirical analysis and appears to be applicable in practice.

• Genomics & Informatics
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• v.14 no.2
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• pp.53-61
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• 2016

Toxoplasma gondii is an intracellular Apicomplexan parasite and a causative agent of toxoplasmosis in human. It causes encephalitis, uveitis, chorioretinitis, and congenital infection. T. gondii invades the host cell by forming a moving junction (MJ) complex. This complex formation is initiated by intermolecular interactions between the two secretory parasitic proteins-namely, apical membrane antigen 1 (AMA1) and rhoptry neck protein 2 (RON2) and is critically essential for the host invasion process. By this study, we propose two potential leads, NSC95522 and NSC179676 that can efficiently target the AMA1 hydrophobic cleft, which is a hotspot for targeting MJ complex formation. The proposed leads are the result of an exhaustive conformational search-based virtual screen with multilevel precision scoring of the docking affinities. These two compounds surpassed all the precision levels of docking and also the stringent post docking and cumulative molecular dynamics evaluations. Moreover, the backbone flexibility of hotspot residues in the hydrophobic cleft, which has been previously reported to be essential for accommodative binding of RON2 to AMA1, was also highly perturbed by these compounds. Furthermore, binding free energy calculations of these two compounds also revealed a significant affinity to AMA1. Machine learning approaches also predicted these two compounds to possess more relevant activities. Hence, these two leads, NSC95522 and NSC179676, may prove to be potential inhibitors targeting AMA1-RON2 complex formation towards combating toxoplasmosis.

• Structural Engineering and Mechanics
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• v.66 no.5
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• pp.665-676
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• 2018

In this study, a four-node quadrilateral partial mixed plate element with low degrees of freedom (dofs) is developed for static and free vibration analysis of functionally graded material (FGM) plates rested on Winkler-Pasternak elastic foundations. The formulation of the presented finite element model is based on a parametrized mixed variational principle which is developed recently by the first author. The presented finite element model considers the effects of shear deformations and normal flexibility of the FGM plates without using any shear correction factor. It also fulfills the boundary conditions of the transverse shear and normal stresses on the top and bottom surfaces of the plate. Beside these capabilities, the number of unknown field variables of the plate is only six. The presented partial mixed finite element model has been validated through comparison with the results of the three-dimensional (3D) theory of elasticity and the results obtained from the classical and high-order plate theories available in the open literature.