• Structural Engineering and Mechanics
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• v.85 no.6
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• pp.825-835
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• 2023

The effective buckling length factor is an important parameter in the elastic buckling analysis of steel structures. The present article aims at developing a new method that allows the determination of the buckling factor values for frames. The novelty of the method is that it considers the interaction between the bracing and the elastic supports for asymmetrical frames in particular. The approach consists in isolating a critical column within the frame and evaluating the rotational and translational stiffness of its restraints to obtain the critical buckling load. This can be achieved by introducing, through a dimensionless parameter 𝜙_i, the effects of coupling between the axial loading and bending stiffness of the columns, on the classical stability functions. Subsequently, comparative, and parametric studies conducted on several frames are presented for assessing the influence of geometry, loading, bracing, and support conditions of the frame columns on the value of the effective buckling length factor K. The results show that the formulas recommended by different approaches can give rather inaccurate values of K, especially in the case of asymmetric frames. The expressions used refer solely to local stiffness distributions, and not to the overall behavior of the structure.

• Structural Engineering and Mechanics
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• v.89 no.2
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• pp.199-211
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• 2024

The loading capacity of engineering structures/components reduces after the initiation and propagation of crack eventually leads to the final failure. Hence, it becomes essential to deal with the crack and its effects at the design and simulation stages itself, by detecting the prone area of the fracture. The phase-field (PF) method has been accepted widely in simulating fracture problems in complex geometries. However, most of the PF methods are formulated with second order continuity theoryinvolving C⁰ continuity. In the present study, PF method based on fourth-order (i.e., higher order) theory, maintaining C¹ continuity has been proposed for ductile fracture simulation. The formulation includes fourth-order derivative terms of phase field variable, varying between 0 and 1. Applications of fourth-order PF theory to ductile fracture simulation resulted in novelty in this area. The proposed formulation is numerically solved using a two-dimensional finite element (FE) framework in 3-layered manner system. The solutions thus obtained from the proposed fourth order theory for different benchmark problems portray the improvement in the accuracy of the numerical results and are well matched with experimental results available in the literature. These results are also compared with second-order PF theory and a comparison study demonstrated the robustness of the proposed model in capturing ductile behaviour close to experimental observations.

• Korean Journal of Cognitive Science
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• v.13 no.1
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• pp.23-40
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• 2002

This study is to examine brain regions that are involved in picture encoding in normal adults using fMRI methods. In Scan 1, the picture encoding was studied during a semantic categorization task in comparison with word. In Scan 2 task type effects were studied both during a picture naming task and during a semantic categorization task with pictures. Subjects were asked to make decision either by pressing a mouse button (Scan 1) or by responding subvocally (naming or saying yes/no) (Scan 2). Regardless of stimulus type, left prefrontal, bilateral occipital, and parietal activations were observed during semantic processing in comparison with fixation baseline. Processing of word stimulus relative to picture resulted in activations in prefrontal and parieto-temporal regions in the left side while that of picture stimulus relative to word resultd in activations in bilateral extrastriatal visual cortices and parahippocampal regions. In spite of the same task demands, stimulus-specific information processings were involved and mediated by different neural substrates; the word encoding was associated with more semantic/lexical processings than pictures and the picture processing associated with more perceptual and novelty related information processings than word. Activations of dorsal part of inferior prefrontal region, i.e., Broca's areas were found both during the picture naming and during the semantic tasks subvocally performed Especially, during the picture naming task, greater occipital activations were found bilaterally relative to the semantic categorization task. indicating a possibility that greater and higher visual processing was involved in retrieving the name referred by picture stimuli.

• The Journal of the Korea Contents Association
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• v.22 no.2
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• pp.487-500
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• 2022

This study aims to examine visitors' usage intention of the mobile AR(Augmented reality) application for tourism in Korea. For this purpose, the study analyzed how three attributes of AR tourguide app such as interactivity, vividness, and novelty have influenced on the tourist in terms of three realms of their flow, their experience (education, entertainment, esthetics, and escapism), and their usage intention for the future. It conducted an online survey from 20 to 30 year-old 291 participants and used a structural equation modeling. Survey findings show that first, novelty has a positive influence on the state of flow in AR application after vividness; Interactivity does not any significant effect on the tourists' flow. Second, when tourists explore the flow in the AR tourguide app, it affects all realms of experience economy of education, entertainment, esthetics, and escapism. Third, when using AR tour guide app in the context of historical heritage site, the two dimensions of entertainment and education influence the usage intention but the other two of esthetics and escapism does not. This study has presented a theoretical contribution that it focuses on historical sites as one type of tourist attractions and suggests a new modeling integrating AR attributes, flow, experience, and usage intention. In addition, it can be used to become a practical reference for revising an user-oriented AR application and customer-tailored AR tourism.

• Information Systems Review
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• v.21 no.1
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• pp.1-22
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• 2019

Mindfulness is the process of actively noticing new things. Today, companies have introduced and run mindfulness programs because the mindfulness has possible applications of productivity and innovation in corporation. However, role of mindfulness has not been clearly investigated in behavior research of Information System. The purpose of this study is to confirm the effects of mindfulness on technology acceptance process. Based on UTAUT Model, we examined how mindfulness in technology acceptance process moderate antecedent factors of acceptance intentions and use behavior. For empirical research, we conducted a survey on acceptance of smart watch of internet of things for employees of companies applying the mindfulness programs. then, we analyzed survey sample in empirical methodologies. Based on the empirical analysis, cognizance of alternative technologies in mindfulness factors increased the impact of performance expectancy on acceptance intention. Novelty seeking in mindfulness factors increased the impact of effort expectancy on acceptance intention. Awareness of local context in mindfulness factors decreased the impact of social influence on acceptance intention. engagement with technology in mindfulness factors increased the impact of facilitating conditions on use behavior. This study suggests academic implications and practical implications based on the results of the research. The implications will help to support and extend the theory of technology acceptance model while providing practical insights for IT acceptance by suggesting ways to utilize mindfulness in corporation.

• Korean Journal of Biological Psychiatry
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• v.19 no.4
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• pp.199-204
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• 2012

Objectives In the previous studies, it has been suggested that temperament and character may affect specialty choice in medical students. The aim of this study is to investigate the effects of temperament and character on specialty interests in medical students. Methods A total 132 third-year medical students initially participated in this study. Among these participants, 128 students had filled out both demographic and Temperament and Character Inventory (TCI) questionnaires. Socio-demographic data, specialty interests and Cloninger's TCI scores were obtained. The specialty interests were categorized into surgical, medical and other departments. Results Among 128 students, 88 (68.7%), 29 (22.7%) and 22 (8.6%) students chose medical, surgical and other departments, respectively. Students choosing surgery departments showed lower Harm Avoidance scores (F = 4.39, df = 1, p = 0.04) and higher Self-Directedness scores (F = 4.30, df = 1, p = 0.04) than those who chose medical departments. There was no significant differences in Novelty Seeking, Reward dependence, Persistence, Cooperativeness, Self-Transcendence scores between groups. Conclusions To the best of our knowledge, this is the first study that has demonstrated the relationship between TCI scores and specialty interests of medical students in Korea. The current study suggests that temperament and character influence specialty interests in medical students. These findings could have implications for medical education research and career counseling.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.33 no.3
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• pp.193-199
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• 2020

This study examines a method for identifying stiffness reductions in structures subjected to seismic loads and retrofitting effects using a combination of the finite element method and an advanced genetic algorithm. The novelty of this study is the application of seismic loading and its response to anomalies in the tested structure. The technique described in this study may enable not only detection of damaged elements but also the identification of their locations and the extent of damage due to seismic loading. To demonstrate the feasibility of the method, the advanced genetic algorithm is applied to frame and truss bridge structures subjected to El Centro and Pohang seismic loads. The results reveal the excellent computational efficiency of the method and its ability to prevent severe damage from earthquakes.

• Journal of the Korea Convergence Society
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• v.8 no.9
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• pp.311-318
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• 2017

This study aims to converge the analysis of institution based view and knowledge based perspectives. Based on the literature review, this study proposed six hypotheses including the moderating effect of institutional characteristics. Hypothesis testing was conducted using PLS(Partial Least Square), which is a structural equation model for 101 start-ups sample. In empirical analysis, all external knowledge characteristics have a positive effect on the knowledge codification capacity. It also positively influenced the performance. The institutional characteristics showed a moderating effects with the novelty of external knowledge and knowledge codification capacity. This study contributes to integrating and analyzing the moderating effects of institution based characteristics with the factor of knowledge based view. Future research needs to analyze the institutional characteristics in a formal and informal way.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.5 no.6
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• pp.317-325
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• 2015

The aim of this research was to investigate the relationship among team learning behavior, individual creativity, team shared mental model(TSMM), mutual performance monitoring on team creativity and then providing the fundamental data on the education. Also it intended to acknowledge relative predictive power on team creativity of independent variables. The total of 257 college students participated the team learning for 6 weeks in a semester. Pearson's product moment correlation and regression analysis were used for data analysis and testing of significance of verification, The main research results are summarized as follows; team learning behavior, TSMM, mutual performance monitoring had no significant effects on three subfactors of team creativity such as novelty, resolution, elaboration & synthesis. Therefore followed researches are needed about inter and intra processing of team creativity.

• Steel and Composite Structures
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• v.50 no.3
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• pp.299-318
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• 2024

The main objective of this paper is to compute the far-field acoustic radiation (sound radiation) of functionally graded plates (FGM) loaded by sinusoidally varying point load subjected to the arbitrary boundary condition is carried out. The governing differential equations for thin functionally graded plates (FGM) are derived using classical plate theory (CPT) and Rayleigh integral using the elemental radiator approach. Four cases, segregated on power-law index k=0,1,5,10, are studied. A novel approach is illustrated to compute sound fields of vibrating FGM plates using the physical neutral surface with an elemental radiator approach. The material properties of the FGM plate for all cases are calculated considering the power law indexes. An in-house MATLAB code is written to compute the natural frequencies, normal surface velocities, and sound radiation fields are analytically calculated using semi-analytical formulation. Ansys is used to validate the computed sound power level. The parametric effects of the power law index, modulus ratios, different constituent of FGM plates, boundary conditions, damping loss factor on the sound power level, and radiation efficiency is illustrated. This work is the benchmark approach that clearly explains how to calculate acoustic fields using a solid layered FGM model in ANSYS ACT. It shows that it is possible to asymptotically stabilize the structure by controlling the intermittent layers' stiffness. It is found that sound fields radiated by the elemental radiators approach in MATLAB, ANSYS and literatures are in good agreement. The main novelty of this research is that the FGM plate is analyzed in the low-frequency range, where the stiffness-controlled region governs the whole analysis. It is concluded that a clamped mono-ceramic FGM plate radiates a lesser sound power level and higher radiation efficiency than a mono-metallic or metal-rich FGM plate due to higher stiffness. It is found that change in damping loss factor does not affect the same constituents of FGM plates but has significant effects on the different constituents of FGM plates.