• International Journal of Fuzzy Logic and Intelligent Systems
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• v.5 no.2
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• pp.119-123
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• 2005

This paper describes a fuzzy-based system for analyzing the stress intensity factors (SIFs) of three-dimensional (3D) cracks. 3D finite element method(FEM) was used to obtain the SIF for subsurface cracks and surface cracks existing in inhomogeneous materials. A geometry model, i.e. a solid containing one or several 3D cracks is defined. Several distributions of local node density are chosen, and then automatically superposed on one another over the geometry model by using the fuzzy theory. Nodes are generated by the bucketing method, and ten-noded quadratic tetrahedral solid elements are generated by the Delaunay triangulation techniques. The singular elements such that the mid-point nodes near crack front are shifted at the quarter-points, and these are automatically placed along the 3D crack front. The complete FE model is generated, and a stress analysis is performed. The SIFs are calculated using the displacement extrapolation method. The results were compared with those surface cracks in homogeneous materials. Also, this system is applied to analyze cladding effect of surface cracks in inhomogeneous materials.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2000.04b
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• pp.43-50
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• 2000

In the first-order shear deformation laminated beam theory (FSDT), the Kirchhoff hypothesis is relaxed such that the transverse normals do not remain perpendicular to the midsurface after deformation. Bending behavior of laminated composite thin-walled beams with singly- and doubly-symmetric open sections under uniformly distributed and concentrated loads is analyzed by the Timoshenko-type thin-walled beam theory. A closed-form expression for the shear correction factor of I-shaped composite laminated section is obtained. Numerical examples are presented to compare present analytical solutions by FSDT with the finite element solutions obtained by using three dimensional model. The effects of lamination of scheme and length-to-height ratio on the shear deformation of laminated composite beams with various boundary conditions are studied.

• Asia pacific journal of information systems
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• v.31 no.4
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• pp.582-605
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• 2021

The study aims to explore the nature, drivers of BAE. In particular, how and why consumers engage with branded mobile apps. Since consumer engagement is a multi-dimensional and complex phenomenon, the authors took an interpretivist paradigm and used a grounded theory approach by interviewing 24 participants. The findings reveal that branded app engagement (BAE) is triggered by mainly three aspects, i.e., media characteristics (Privacy and security, customization, and convenience), brand-related aspects (brand image and product/service quality), and benefits sought (inherent and derived). More importantly, we uncover the underlying mechanism for each factor. Furthermore, the study explains the BAE process in its entirety from an app-centric perspective rather the brand powering the app. Thus, the study offers a fresh perspective and novel insights into the BAE process.

• Korean Journal of Oriental Medicine
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• v.10 no.2
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• pp.37-49
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• 2004

In the existing Medical Literatures in Korea and China, there is neither the same book name nor same contents of the Medical Book named ${\ulcorner}$Yoryak(要略)${\lrcorner}$, but in viewing of the different name as written as ${\ulcorner}$GyoinYoryak(敎人要略)${\lrcorner}$, it is considered that written as an unpublished manuscript-book for the purpose of Medical Education in the latter period of Chosun Dynasty. While the author, Songgyesanin(松溪散人) is even anonymous as yet, it is regarded that he was much familiar with medical science as a secluded ascetic aiming for Taoism-like Life In ${\ulcorner}$Yoryak${\lrcorner}$, the contents of Taoism Literature named as ${\ulcorner}$OjangYukbudo(五臟六腑圖)${\lrcorner}$ which was regarded that had been actually initiated since ${\ulcorner}$Euibangyoochui(醫方類聚)${\lrcorner}$ is being quoted thereat, also it attempts to combine with ${\ulcorner}$DonguiBogam(東醫寶鑑)${\lrcorner}$, the typical Medical Literature of Chosun Dynasty. With reference to Cause of Disease, since Chin Moo-Taek(陳無擇) asserted 'Theory of Three-Causes(三因說)' in his Book ${\ulcorner}$Samin Keukilbyungjeung Bangron(三因極一病證方論)${\lrcorner}$, it effects many influences to the coming generation, However, on coming up to ${\ulcorner}$Yoryak${\lrcorner}$, the medical science book of Chosun Dynasty, the 'Theory of Two-Causes(二因說)' which consisted of 'Internal Causes by Seven Emotions' and 'Exterior Causes by Six Harmful Surroundings' is also being asserted. In accordance with this Theory, it refers to the 'Seven Emotions(七情)' as the fundamental factor to possibly weaken the viscera and entrails, and also regards that the Exterior Harmful Surroundings invade to body when the viscera and entrails are under weakened condition. Therefore, since Cause of Disease naming as 'Cause Theory at Neither Interior Nor Exterior' is not tolerable in such Diagnostic System, it is daringly advocating the 'Two Causes Theory', getting free from the viewpoint of 'Three Causes Theory' that Chin Moo-Taek has ever maintained.

• Journal of the Korean Operations Research and Management Science Society
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• v.31 no.2
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• pp.41-55
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• 2006

RFID (Radio Frequency IDentification) is a wireless frequency recognition technology that can be used to recognize, trace, and Identify people, things and animals using radio frequency. Although current RFID technology can provide wide advantages in many fields, most companies do not consider widely adopting this technology yet. This paper presents RFID implementation as a technology innovation. This research selects three affecting factors of IT infrastructure, fitness of Tag, fitness of Frequency, and one moderator of the power of business partners, on RFID adoption based on innovation model, and then empirical survey is conducted among the companies using RFID technology or planing for RFID adoption to investigate the relationship of three affacting factors and one moderator factor. Reserachers can find the direction to activate RFID technology as a competitive advantage.

• Computers and Concrete
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• v.19 no.6
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• pp.725-736
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• 2017

This paper presents the two-, three-, and four-lane transverse reduction factor based on FEA method, probability theory, and the recently actual traffic flow data. A total of 72 composite girder bridges with various spans, number of lanes, loading mode, and bridge type are analyzed with time-varying static load FEA method by ANSYS, and the probability models of vehicle load effects at arbitrary-time point are developed. Based on these probability models, in accordance to the principle of the same exceeding probability, the multi-lane transverse reduction factor of these composite girder bridges and the relationship between the multi-lane transverse reduction factor and the span of bridge are determined. Finally, the multi-lane transverse reduction factor obtained is compared with those from AASHTO LRFD, BS5400, JTG D60 or Eurocode. The results show that the vehicle load effect at arbitrary-time point follows lognormal distribution. The two-, three-, and four-lane transverse reduction factors calculated by using FEA method and probability respectively range between 0.781 and 1.027, 0.616 and 0.795, 0.468 and 0.645. Furthermore, a correlation between the FEA and AASHTO LRFD, BS5400, JTG D60 or Eurocode transverse reduction factors is made for composite girder bridges. For the two-, three-, and four-lane bridge cases, the Eurocode code underestimated the FEA transverse reduction factors by 27%, 25% and 13%, respectively. This underestimation is more pronounced in short-span bridges. The AASHTO LRFD, BS5400 and JTG D60 codes overestimated the FEA transverse reduction factors. The FEA results highlight the importance of considering span length in determining the multi-lane transverse reduction factors when designing two-lane or more composite girder bridges. This paper will assist bridge engineers in quantifying the adjustment factors used in analyzing and designing multi-lane composite girder bridges.

• The Journal of Pediatrics of Korean Medicine
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• v.19 no.2
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• pp.51-68
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• 2005

Objective : Rumenshiqin(儒門事親) was compiled by Zhang Zi Huo(張子和) of the Jin(金) Dynasty of China. He invented unique medical theory and treatment such as three excretive methods(perspiratory, vomitory and purgative therapy). The aim of this study was to make the best use of the therapeutic theory of Rumenshiqin(儒門事親) connected with pediatrics. Methods: We conducted literature search in detail for contents of Rumenshiqin(儒門事親) and reviewed various kinds of books. Results : Zhang Zi Huo(張子和) recognized that children had pure-yang bodies(純陽之體) and emphasized that children need to prevent heat-stagnation(鬱熱) and asthenic yin(損陰). He instructed that a principle of raising such as wearing thin clothes, eating fresh food, harboring little desire and little anger, and taking temperate medicine. He described that pathogenic factors were mistake of rearing, misuse of medicine, exogenous factor, and excessive emotion. Conclusion : According to the above results, it is concluded that his therapeutic theory should be used at present.

• Steel and Composite Structures
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• v.41 no.6
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• pp.805-820
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• 2021

In this research, the buckling and free vibration of three-phase carbon nanotubes/ fiber/ polymer piezoelectric nanocomposite face sheet sandwich microbeam with microsensor and micro-actuator surrounded in elastic foundation based on modified couple stress theory (MCST) is investigated. Three types of porous materials are considered for sandwich core. Higher order (Reddy) and sinusoidal shear deformation beam theories are employed for the displacement fields. Sinusoidal surface stress effects are extracted for sinusoidal shear deformation beam theory. The equations of motion are derived by Hamilton's principle and then the natural frequency and critical buckling load are obtained by Navier's type solution. The determined results are in good agreement with other literatures. The detailed numerical investigation for various parameters is performed for this microsensor-microactuator. The results reveal that the microsensor-microactuator enhanced by increasing of Skempton coefficient, carbon nanotubes diameter length to thickness ratio, small scale factor, elastic foundation, surface stress constants and reduction in porous coefficient, micro-actuator voltage and CNT weight fraction. The valuable results can be expedient for micro-electro-mechanical (MEMS) and nano-electro-mechanical (NEMS) systems.

• Advances in nano research
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• v.8 no.4
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• pp.293-305
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• 2020

In the current research, the free vibrational behavior of the FG nano-beams integrated in the hygro-thermal environment and reposed on the elastic foundation is investigated using a novel integral Timoshenko beam theory (ITBT). The current model has only three variables unknown and requires the introduction of the shear correction factor because her uniformed variation of the shear stress through the thickness. The effective properties of the nano-beam vary according to power-law and symmetric sigmoid distributions. Three models of the hygro-thermal loading are employed. The effect of the small scale effect is considered by using the nonlocal theory of Eringen. The equations of motion of the present model are determined and resolved via Hamilton principle and Navier method, respectively. Several numerical results are presented thereafter to illustrate the accuracy and efficiency of the actual integral Timoshenko beam theory. The effects of the various parameters influencing the vibrational responses of the P-FG and SS-FG nano-beam are also examined and discussed in detail.

• Journal of the Korean Geotechnical Society
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• v.35 no.3
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• pp.17-24
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• 2019

The purpose of this study is to understand the characteristics of bearing capacity of shallow foundation on the grounds. We made a comparative study of existing bearing capacity theory, based on the three-dimensional finite element analysis with a variety of conditions such as ground condition, foundation scale and foundation shape. In the finite element analysis, the ultimate bearing capacity showed a gradual convergence in the form of exponential function or logarithm function according to the foundation scale. Although the shear strength increased, the bearing capacity tended not to increase but change linearly. In the results of comparative study of existing bearing capacity theory, bearing capacity ratio ($q_{u(FEA)}/q_{u(theory)}$) of pure sand has the outcome closest to those of the Terzaghi method. Pure clay turned out to be about 0.4~0.6 while normal soil was changed in a range of 0.3~1.3. As shear strength is increased, the results turned out to be less than 1.0. Bearing capacity ratio ($q_u/q_{u(1.0)}$), normalized at 1.0m bearing capacity, was about 35%, 15% and 5% of theoretical formula under the condition of ${\phi}=25^{\circ}$, $30^{\circ}$ and $35^{\circ}$ of pure sand; no scale effect was found with pure clay and the normal soil with lower soil strength level showed less than 10% of the theoretical formula of pure sand. Bearing capacity ratio of each case, in accordance with, the shear strength increase, was largely influenced by the internal friction angle. Shape factor of bearing capacity ratios classified by foundation shapes have different results according to the shapes; the shape factor of circular foundation is 1.50, square foundation is 1.30, rectangular and continuous foundations are 1.1~1.0.