• Bulletin of the Korean Mathematical Society
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• v.56 no.4
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• pp.993-1006
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• 2019

This article concerns a ring property which preserves the reversibility of elements at nonzero idempotents. A ring R shall be said to be quasi-reversible if $0{\neq}ab{\in}I(R)$ for a, $b{\in}R$ implies $ba{\in}I(R)$, where I(R) is the set of all idempotents in R. We investigate the quasi-reversibility of 2 by 2 full and upper triangular matrix rings over various kinds of reversible rings, concluding that the quasi-reversibility is a proper generalization of the reversibility. It is shown that the quasi-reversibility does not pass to polynomial rings. The structure of Abelian rings is also observed in relation with reversibility and quasi-reversibility.

• Journal of the Korean Data Analysis Society
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• v.20 no.6
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• pp.2747-2757
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• 2018

We consider the MLE (maximum likelihood estimate) and Bayesian estimates of three-parameter bathtub-shaped lifetime distribution based on the progressive type II censoring with binomial removal. Jung, Chung (2018) proposed the three-parameter bathtub-shaped distribution which is the extension of the two-parameter bathtub-shaped distribution given by Zhang (2004). Jung, Chung (2018) investigated its properties and estimations. The maximum likelihood estimates are computed using Newton-Raphson algorithm. Also, Bayesian estimates are obtained under the balanced loss function using MCMC (Markov chain Monte Carlo) method. In particular, BSEL (balanced squared error loss) function is considered as a special form of balanced loss function given by Zellner (1994). For comparing theirs MLEs with the corresponding Bayes estimates, some simulations are performed. It shows that Bayes estimates is better than MLEs in terms of risks. Finally, concluding remarks are mentioned.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.35 no.11
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• pp.171-180
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• 2019

This research proposed the Direct Construction System for construction corporations as a strategy intended to perform cause analysis of construction technician shortage matter and solve resulting problems, and in view of the outcomes from the application of this system to the projects and workshops, it was verified that unsteady employment, lack of career prospect, and conditions of work environment can be resolved. In addition, from corporations' perspective, it is considered that by clarifying the abovementioned three problems, fundamental complications of construction administration, quality control, safety supervision, and cost management were settled, concluding forthcoming advancement of domestic construction business quality fell far behind developed counties.

• Acta Via Serica
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• v.8 no.1
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• pp.55-70
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• 2023

Carpets are a useful tool for highlighting the cultural uniqueness of a region because their characteristic usage often reveals distinctive natural features of the place or the unique cultural identity of a group. Investigating anecdotes and associated patterns found in three medieval trans-Eurasian travelogues, this paper focuses on observations made by the Chinese Buddhist monk, Faxian, the Sunni pilgrim and scholar, Ibn Battuta, and Marco Polo, the Venetian merchant examining their thoughts, observations, and perspectives on carpet-related customs in their experienced contexts. In particular, this manuscript touches on the controversies, impacts, and narratives associated with carpet practices observed in each travel writer's context respectively, concluding that each traveler shows several things in common rather than showing different patterns depending on the characteristics of their religion. Overall, they observed the uses of carpets according to their jobs and travel purposes and appropriately detailed related episodes if the intended purpose and context matched the uses.

• International Journal of High-Rise Buildings
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• v.12 no.4
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• pp.299-306
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• 2023

An overview of seismic isolation and structural control in Japan is presented. The paper includes a mention of the history of aseismic technology and the earthquake threat in Japan, summarizes the merits of seismic isolation and response control, and discusses the types of devices used and some recent project examples. The projects presented are mostly examples of response control used for high-rise buildings. These types of buildings are not amendable to seismic isolation, and are a challenge to applying damping devices, as their high aspect ratio means that their dominant deformation mode is bending. Japanese engineers have developed a range of unique techniques to apply response control to these types of structures. Concluding remarks discuss some of the current challenges to expanding the use of seismic isolation and response control technologies.

• Lingua Humanitatis
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• v.2 no.2
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• pp.283-299
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• 2002

The Contemporary Korean fiction today to a certain context infringes on the outskirts of mainstream literary theories diversified to an extent that anything and everything that are printed are defined as literature. The two fictions that the study is based upon, probably, shows the effects of postmodernism in Korean fictional 'space' in that the representation of the said fictions veers clear from that with which one might associate in contemplating the traditional Korean fiction. The study, though it seems, based on a more of a societal perspective rather than traditional literary perspective is to be noted in reference with the postmodern theories that we identity with today. The paper takes look at the changes that can be noted in the fictions: Kyung ma jang ga nun gil by Ha Il-ji and Oak tap hang by Park Sang-woo. The main objective of the paper is that it tried to identify the cultural identity of Koreans through the descriptions found in the two works. While concluding as to why these two fictions can be categorized as belonging to the genre of postmodernism the research also tries to formulate what and how postrnodernism can be discerned in fictional genre and this especially in today's Contemporary Korean fiction.

• Transactions on Electrical and Electronic Materials
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• v.13 no.2
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• pp.64-68
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• 2012

We have successfully demonstrated a bandgap alteration of transparent zinc oxide (ZnO) thin film with Mg dopant by using sol-gel spin coating technique. By increasing the dopant from 0 to 30 atomic percent (at.%), a decrement value in the cutoff is observed, where the absorption edge shifts continuously to the shorter wavelength side, towards 300 nm. This resulted in a significant bandgap increment from 3.28 to 3.57 eV. However, the transmittance of the thin film at 350-800 nm gradually downgraded, from 93 to 80 % which is most probably due to the grain size that becomes bigger, and it also affected the electrical properties. The decrement from 45 to 0.05 mA at +10 V was observed in the I-V characteristics, concluding the significant relationship; where higher optical bandgap materials will exhibit lower conductivity. These findings may be useful in optoelectronics devices.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.12
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• pp.1073-1087
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• 2020

The purpose of this paper is to (1) evaluate a proposed conceptual model based on integrated Technology Acceptance Model (TAM) and Corporate Social Responsibility (CSR); (2) compare the differences between Vietnam and South Korea regarding the effects of consumer perception of CSR activities and technology acceptance on intention to adopt mobile banking. Structural Equation Modeling (SEM) was conducted to analyze the data collected from the field survey questionnaires administered to a convenience sample of Vietnamese and Korean banking customers. The results showed that there is a difference between South Korea and Vietnam with regard to intention to use mobile banking services. While the effects of social responsibility and environmental responsibility on trust, trust on perceived usefulness, perceived risk on intention to use, perceived usefulness on intention to use were significant in the context of Vietnam but those effects were not significant in South Korea. Therefore, this study has attempted to fill this gap by empirically examining some of the important factors influencing the adoption of m-banking from the Vietnamese and Korean customers' perspectives. Finally, practical and theoretical implications for both banks and researchers in the m- banking context are also discussed in the concluding section.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2005.04a
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• pp.249-256
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• 2005

Rigorous FE(Finite Element) analyses of the cable-stayed bridge with steel-box girder, the main construction method of which is FCM (Free Cantilever Method), are presented in this paper. The analysis and the checking of design for a derrick crane under several loading conditions are performed using the software MIDAS/Civil and the beam elements are used to model the main structure. Among all the construction stages, special construction stages are chosen and considered to ensure the safety of segments of box girder The stress analysis for lifting of a segment of box girder is performed using the software SAP2000 and the shell elements of which having 6 DOF(Degrees Of Freedom) per nodes are successfully used to model the segment of box girder for the purpose of capturing the detailed behaviors on the folded-plates in the segment. Finally, concluding remarks are given to improve a design of the derrick crane and the segment based on the results from this study.

• Structural Engineering and Mechanics
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• v.65 no.5
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• pp.557-572
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• 2018

The academic research works about liquid storage tanks are reviewed for the purpose of providing valuable reference to the engineering practice on their aseismic design. A summary of the performance of tanks during past earthquakes is described in this paper. Next, the seismic response of tanks under unidirectional earthquake is reported, supplemented with the dynamic response under multidirectional motions. Then, researches on the influence of soil-structure interaction are brought out to help modify the seismic design approach of tanks in different areas with variable properties of soils. Afterwards, base isolation systems are reported to demonstrate their effectiveness for the earthquake-resistant design of liquid storage tanks. Further, researches about the liquid-structure interaction are reviewed with description of simplified models and numerical analytical methods, some of which consider the elastic effect of tank walls. Moreover, the liquid sloshing phenomenon on the hydrodynamic behaviors of tanks is presented by various algorithms including grid-based and meshfree method. And then the impact of baffles in changing the dynamic characteristics of the liquid-structure system is raised, which shows the energy dissipation by the vortex motion of liquid. In addition, uplifting effect is given to enhance the understanding on the capacity of unanchored tanks and some assessment of their development. At last, the concluding remarks and the aspects of extended research in the field of liquid storage tanks under seismic loads are provided, emphasizing the thermal stress analysis, the replaceable system for base isolation, the liquid-solid interaction and dynamic responses with stochastic excitations.