• 한국재료학회지
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• 제4권5호
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• pp.590-599
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• 1994

취성재료의 균열첨단에서 전위의 이동에 대한 거동을 이해하기 위하여 단결정의 알루미나에 대한 취성-연성 전이(BDT)에 대한 한 연구가 진행되었다. 여러 온도에서, 예비균열된 시편으로 4점 굽힘시험을 이용하여 임계응력확대계수와 항복강도가 측정되었다. 그 결과로, BDT온도는 변형속도와 시편 방향에 따라 달랐다.:(1120)파단면에 대하여 $4.2 \times 10^{-6}$와 $4.2 \times 10^{-7}s^{-1}$에서 BDT온도는 각각$1034^{\circ}C$, $1150^{\circ}C$이었다. 또한 4점굽힘 시험을 이용하여 연성영역에서 균열첨단으로 부터 방출된 전위의 이동거리과 방향은 에칭 피트법에 의해서 측정되었다. 이중 에칭법을 이용하여 즉정된 사파이어에서 전위의 이동속도는 모델링 연구에 응용되었다.

• The Journal of Asian Finance, Economics and Business
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• 제8권9호
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• pp.321-331
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• 2021

This study examines the impact of Information and Communication Technology (ICT) and the role of Malaysian local wisdom called "Ugahari" in managing Work-Life Balance (WLB) during the COVID-19 pandemic in Malaysia. Data was obtained through online and offline surveys which were distributed to the agencies in the public and private sectors spread across Kuala Lumpur, Selangor and Pura Jaya. Overall 466 respondents were found to have given valid and complete responses. This research utilized the Partial Least Squares Structural Equation Modelling. It was found that the use of the ICT during Work from Home (WFH) helped workers to have relatively high flexibility where they could easily expand or contract one domain to meet the demands of another domain. At the same time it also offered high permeability where aspects of one domain entered another domain. This encourages workers to integrate their roles and achieve broad work autonomy. Furthermore, this situation then gives rise to a high level of interference at the boundary between work and family domains. On the other hand Ugahari reduces the level of interference caused by ICT use and encourages workers to compartmentalize their respective roles. Thus, ICT and Ugahari's behavior can play a role and complement each other in the context of realizing worker well-being.

• 식품보건융합연구
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• 제7권2호
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• pp.1-10
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• 2021

The purpose of this study is to examine the impact of the service quality of delivery food on customers' emotional response and repurchase intention during the COVID19 pandemic. The proposed research model examined the effect on the service quality, customer sentiment response, and repurchase intention of delivery food. A questionnaire was distributed and measured for 300 consumers who had experience using food delivery services in the last 30 days. The questionnaires from previous researches were revised to fit the purpose of the present study. The survey results were analyzed to verify the reliability and validity of the measured variables. To verify the hypotheses a Structural Equation Modelling (SEM) was used for the study. The results showed that taste, price fairness, and package design positively affected emotional response; moreover, repurchase intention was enhanced by emotional response. This research analyzed the relationships between service qualities of delivery food, emotional response, and repurchase intention when customers consume delivery food during COVID19 in Korea. This study extends the delivery food literature by combining customers' emotional behavior with SEM model. The result suggested competitive strategic plans and development directions of food delivery companies in the rapidly increasing food delivery industry, providing implications for further research.

• 대한건축학회논문집:계획계
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• 제35권9호
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• pp.3-9
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• 2019

Modern cities have been clustered with spaces defined by specific functions, while standardized with well-defined areas. The monopoly of the function reduces the publicity of the space and hinders people's daily communication. Street also be overwhelmed by the function of being a "passage", traditional streets were losing their liminality. In fact, the street was a place of meeting, a place of events, and a place of freedom to broaden the choices of behavior. The freedom to stop or walk on one'sits own, be attracted by unforeseen events that are available on traditional streets, has become rare on the streets of big cities. Life has become dull and monotonous, too, through the modelling of the street system. Cities have become grim as communities are cut off and fragmented. In today's big cities, public attention to the liminality of the traditional streets need to be aroused so that people could gather freely and have a festival time.

• The Journal of Asian Finance, Economics and Business
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• 제8권4호
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• pp.959-969
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• 2021

This study aims to develop new constructs and indicators for sharia destination image, and then examine its effects on perceived value, tourist satisfaction, and post-visit behaviour. Furthermore, it analyses the mediating role of perceived value and tourist satisfaction on relationship between sharia destination image and post-visit behaviour. The population were domestic and Malaysian Muslim tourists who visited Aceh during the study period. The sampling was carried out in two stages. The first stage involved selecting most visited districts. The second stage involved randomly selecting tourists who visit during the study period in the districts. Data was collected using a structured questionnaire with a Likert scale. Also, a total of 270 questionnaires were distributed to domestic and Malaysian tourists in Aceh. Cluster sampling was used to determine the sample area, and purposive sampling technique was used to determine the study sample. Furthermore, the data analysis technique is Structural Equation Modelling. The results showed that the sharia destination image has a significant effect on perceived value. Meanwhile, the perceived value significantly influenced tourist satisfaction and post-visit behaviour. In addition, the perceived value and tourist satisfaction can mediate the effects of sharia destination image, which has no direct effect on post-visit behaviour.

• Advances in nano research
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• 제13권1호
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• pp.13-28
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• 2022

The pumpability of the grouts is significant issue in concept of the rheological and workability properties during penetrating to voids and cracks. To improve the fluidity features of the grout mixes, the usage of Colloidal Nano Particular Powders (CNPPs) with mineral additives such as fly ash (FA) can contribute. Therefore, the main purpose of this study can be explained as investigating the usage effects of four types of Colloidal Nano Particular Powders (n-TiO₂, n-ZnO, n-Al₂O₃ and n-SiO₂) as nano additives on the rheological, workability and bleeding properties of cement-based grout incorporated with fly as. Test results showed that the usage of FA in the grout samples positively contribute to increase on the fluidity of the grout samples as expected. The dilatant behavior was observed from the results for all mixes. Observing the effect of nano-sized additives in such cement-based grout mixtures with high fluidity has presented remarkable effects in this study.

• Structural Monitoring and Maintenance
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• 제9권1호
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• pp.81-105
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• 2022

The use of concrete filled steel tube (CFST) column is widely accepted due to its property of high axial load carrying capacity, more ductility and more resistant to earthquake specially using in bridges and high-rise buildings. The initial imperfection (δ) that produces during casting or fixing causes the reduction in load carrying capacity, this is the reason, experimental capacity is always less then theoretical one. In this research, the effect of δ on load carrying capacity and behavior of concrete filled steel tube (CFST) column have been investigated by numerically simulation of large number of models with different δ and other geometric parameters that include length (L), width (B), steel tube thickness (t), f'_c and f_y. Finite element analysis software ANSYS v18 is used to develop model of SCFST column to evaluate strength capacity, buckling and failure pattern of member which is applied during experimental study under cyclic axial loading. After validation of results, 42 models with different parameters are evaluated to develop empirical equation predicting axial load carrying capacity for different value of δ. Results indicate that empirical equation shows the 0 to 9% error for finite element analysis Forty-two models in comparison with ANSYS results, respectively. Empirical equation can be used for predicting the axial capacity of early estimating the axial capacity of SCFT column including 𝛿.

• Earthquakes and Structures
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• 제21권5호
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• pp.477-487
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• 2021

This study focuses on the influence of strong ground motion duration on the response and collapse probability of reinforced concrete walls with a predominant response in flexure. Walls with different height and mass were used to account for a broad spectrum of configurations and fundamental periods. The walls were designed following the specifications of the Chilean design code. Non-linear models of the reinforced concrete walls using a distributed plasticity approach were performed in OpenSees and calibrated with experimental data. Special attention was put on modeling strength and stiffness degradation. The effect of duration was isolated using spectrally equivalent ground motions of long and short duration. In order to assess the behavior of the RC shear walls, incremental dynamic analyses (IDA) were performed, and fragility curves were obtained using cumulative and non-cumulative engineering demand parameters. The spectral acceleration at the fundamental period of the wall was used as the intensity measure (IM) for the IDAs. The results show that the long duration ground motion set decreases the average collapse capacity in walls of medium and long periods compared to the results using the short duration set. Also, it was found that a lower median intensity is required to achieve moderate damage states in the same medium and long period wall models. Finally, strength and stiffness degradation are important modelling parameters and if they are not included, the damage in reinforced concrete walls may be greatly underestimated.

• Advances in Computational Design
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• 제8권2호
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• pp.97-112
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• 2023

The Finite Element (FE) modeling of Reinforced Concrete (RC) under seismic loading has a sensitive impact in terms of getting good contribution compared to experimental results. Several idealized model types for simulating the nonlinear response have been developed based on the plasticity distribution alone the model. The Continuum Models are the most used category of modeling, to understand the seismic behavior of structural elements in terms of their components, cracking patterns, hysteretic response, and failure mechanisms. However, the material modeling, contact and nonlinear analysis strategy are highly complex due to the joint operation of concrete and steel. This paper presents a numerical simulation of a chosen RC column under monotonic and cyclic loading using the FE Abaqus, to assessthe hysteretic response and failure mechanisms in the RC columns, where the perfect bonding option is used for the contact between concrete and steel. While results of the numerical study under cyclic loading compared to experimental tests might be unsuccessful due to the lack of bond-slip modeling. The monotonic loading shows a good estimation of the envelope response and deformation components. In addition, this work further demonstrates the advantage and efficiency of the damage distributions since the obtained damage distributions fit the expected results.

• Advances in nano research
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• 제12권3호
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• pp.253-261
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• 2022

Numerical modelling of an integrated Carbon NanoTube (CNT) membrane is only achievable if probable deformations and realistic alterations from a perfect CNT membrane are taken into account. Considering the possible forms of CNTs, bending is one of the most probable deformations in these high aspect ratio nanostructures. Hence, investigation of effect associated with bent CNTs are of great interest. In the present study, molecular dynamics simulation is utilized to investigate fluid flow dynamics in deformed CNT membranes, specifically when the tube cross section is not affected. Bending in armchair (5,5) CNT was simulated using Tersoff potential, prior to flow rate investigation. Also, to study effect of inclined entry of the CNT to the membrane wall, argon flow through generated inclined CNT membranes is examined. The results show significant variation in both cases, which can be interpreted as counter-intuitive, since the cross section of the CNT was not deformed in either case. The distribution of fluid-fluid and fluid-wall interaction potential is investigated to explain the anomalous behavior of the flow rate versus bending angle.