• Atmosphere
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• v.31 no.4
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• pp.395-404
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• 2021

In order to investigate downslope windstorm by using more detailed observation, we observed 6 cases at 3 sites - Inje, Yongpyeong, and Bukgangneung - during "3-D Meteorological Observation Project in Yeongdong region of Gangwon province, South Korea in 2020." The results from analysis of the project data were as follows. First, AWS data showed that a subsidence inversion layer appeared in 800~700 hPa on the windward side and 900~850 hPa on the leeward side. Second, before strong wind occurred, the inversion layer had descended to about 880~800 hPa. Third, with mountain wave breaking, downslope wind was intensified at the height of 2~3 km above sea level. After the downslope wind began to descend, the subsidence inversion layer developed. When the subsidence inversion layer got close to the ground, wind peak occurred. In general, UM (Unified Model) GDAPS (Global Data Assimilation Prediction System) have had negative bias in wind speed around peak area of Taebaek mountain range, and positive bias in that of East Sea coast area. The stronger wind blew, the larger the gap between observed and predicted wind speed by GDAPS became. GDAPS predicted strong p-velocity at 0600 LST 25 Apr 2020 (4^th case) and weak p-velocity at 2100 LST 01 Jun 2020 (6^th case) on the lee-side of Taebaek mountain range near Yangyang. As hydraulic jump theory was proved, which is known as a mechanism of downslope windstorm in Yeongdong region, it was confirmed that there is a relationship between p-velocity of lee-side and wind speed of eastern slope of Taebaek mountain range.

• Journal of Convergence for Information Technology
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• v.11 no.10
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• pp.101-114
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• 2021

This study aimed to analyze the degree of consumers' expectations for their performance and efforts in using overseas direct purchase, impact of overseas direct purchase on the society, and effect of price value to their intention to use overseas direct purchase in the future. In addition, the significance of overseas direct purchase on the user-perceived availability is empirically analyzed. As a result of the study, it was confirmed that performance expectancy, effort expectancy, social influence, and price value showed significantly positive effect on the intention to use overseas direct purchase in the future. With respect to the perceived availability in using overseas direct purchase, it was found out that effort expectancy and price value had significantly positive effect; however, it appeared that performance expectancy and social influence had no significant effect on the perceived availability of the users.

• Journal of Multimedia Information System
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• v.5 no.4
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• pp.283-290
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• 2018

Smarthome is one of the remarkable fields of the industrial revolution 4.0, which are popular in many countries such USA, EURO, Japan and Korea. However, how Vietnamese people are considering and having intension to use smarthome devices is still a question for marketers and researchers. This study develops a comprehensive research model that can explain potential customers' behavioral intentions to adopt and use Smarthome services in Viet Nam and figure which key factors affect the intention. This study proposes and validates a new theoretical model that extends the Unified Theory of Acceptance and Use of Technology 2 (UTAUT2). The model consists of eight factors that affect one element (Behavioral Intention), specifically: Habits, Perceived usefulness, Perceived ease of use, Trust, Innovativeness Personal, Perceived value, Hedonic motivations and Social influences. Data were collected from 304 Vietnamese citizens by sending the email to survey questionnaire, direct contact with the experienced smarthome users. Through regression analysis, data from samples were analysed with SPSS 20 software and verification of hypotheses, the results show the key determinants affecting the intention to use smarthome appliances in Vietnam: Perceived Value, Social Influence, Perceived Usefulness, Perceived Ease of Use and Trust. From this result, several recommendations have been suggested to to smarthome devices vendors and marketer to improve products as well as marketing approaches to meet customer needs.

• Coupled systems mechanics
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• v.7 no.6
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• pp.649-668
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• 2018

In this paper, we present a numerical model for fluid-structure interaction between structure built of porous media and acoustic fluid, which provides both pore pressure inside porous media and hydrodynamic pressures and hydrodynamic forces exerted on the upstream face of the structure in an unified manner and simplifies fluid-structure interaction problems. The first original feature of the proposed model concerns the structure built of saturated porous medium whose response is obtained with coupled discrete beam lattice model, which is based on Voronoi cell representation with cohesive links as linear elastic Timoshenko beam finite elements. The motion of the pore fluid is governed by Darcy's law, and the coupling between the solid phase and the pore fluid is introduced in the model through Biot's porous media theory. The pore pressure field is discretized with CST (Constant Strain Triangle) finite elements, which coincide with Delaunay triangles. By exploiting Hammer quadrature rule for numerical integration on CST elements, and duality property between Voronoi diagram and Delaunay triangulation, the numerical implementation of the coupling results with an additional pore pressure degree of freedom placed at each node of a Timoshenko beam finite element. The second original point of the model concerns the motion of the outside fluid which is modeled with mixed displacement/pressure based formulation. The chosen finite element representations of the structure response and the outside fluid motion ensures for the structure and fluid finite elements to be connected directly at the common nodes at the fluid-structure interface, because they share both the displacement and the pressure degrees of freedom. Numerical simulations presented in this paper show an excellent agreement between the numerically obtained results and the analytical solutions.

• Steel and Composite Structures
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• v.31 no.1
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• pp.13-25
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• 2019

Reactive powder concrete (RPC) is a type of ultra-high strength concrete that has a relatively high brittleness. However, its ductility can be improved by confinement, and the use of RPC in composite RPC filled steel tube columns has become an important subject of research in recent years. This paper aims to present an experimental study of axial capacity calculation of RPC filled circular steel tube columns. Twenty short columns under axial compression were tested and information on their failure patterns, deformation performance, confinement mechanism and load capacity were presented. The effects of load conditions, diameter-thickness ratio and compressive strength of RPC on the axial behavior were further discussed. The experimental results show that: (1) specimens display drum-shaped failure or shear failure respectively with different confinement coefficients, and the load capacity of most specimens increases after the peak load; (2) the steel tube only provides lateral confinement in the elastic-plastic stage for fully loaded specimens, while the confinement effect from steel tube initials at the set of loading for partially loaded specimens; (3) confinement increases the load capacity of specimens by 3% to 38%, and this increase is more pronounced as the confinement coefficient becomes larger; (4) the residual capacity-to-ultimate capacity ratio is larger than 0.75 for test specimens, thus identifying the composite columns have good ductility. The working mechanism and force model of the composite columns were analyzed, and based on the twin-shear unified strength theory, calculation methods of axial capacity for columns with two load conditions were established.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.21 no.6
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• pp.83-93
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• 2018

In Germany has a long history of ecological restoration and restoration management. At the beginning of the 1990s, the "Erfolgskontrolle" was used as an evaluation program after the restoration project and many exchanges of views took place. It is the time, in Korea, there is a need for a comprehensive evaluation program after the restoration project, as there is no evaluation method yet. At this time it may be the "Erfolgskontrolle" in Germany as a practical model for the Korean restoration management program. The purpose of this study is to identify the concept and character of the "Erfolgskontrolle" and to demonstrate the implication and potential of application, through the analysis of the implementation example of the revaluation of river revitalization. To achieve the goal was carried out theoretical and 3 exemplary revitalization research cases. And it was endeavored to deliver the German way of acting and the basic idea to Korea. For the restoration, the "precautionary principle" should be considered first, the upper legal regulation should not be violated. In order to apply "Erfolgskontrolle" in practice, the goal formulation should be clear and systematically evaluated. And through the collection of typified cases, the comprehensive and unified theory should be established, it is possible, thus the qualitative assessment of the restoration project.

• Journal of Digital Convergence
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• v.17 no.5
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• pp.157-165
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• 2019

The objective of this study is to identify the relationship between tourists' intention upon UTAUT and purchase intention on tourism omnichannel considering moderating effect of trust and purchase propensity. As the results, 1) there are partially significant and positive relationship between tourists' intention and purchase intention. There are partially significant and positive moderating effect of 2) trust and 3) purchase propensity upon the relationship between tourists' intention and purchase intention on tourism omnichannel. In order to increase the purchase intention of diversified customers, it is necessary to secure the reliability of OmniChannel which integrates the on-off line, for the future, more in-depth study of purchase propensity of tourism omnichannel should be needed.

• Journal of the Korea Society of Computer and Information
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• v.24 no.10
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• pp.101-116
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• 2019

In this paper, we propose a novel behavioral model that explains the use of the military battlefield management system more effectively in the non-voluntary use environment. This study intends to suggest a model based on the Unified Theory of Acceptance and Use of Technology(UTAUT), an extended TAM. Also, it introduces the concept of 'Conative IS use' as a dependent variable that can explain user's behavior more effectively in non-voluntary technology acceptance environment. In addition, we propose the major factors affecting the UTAUT components from the TOE(Technology-Organization-Environment) perspectives, and analyze their effects. In order to validate the proposed model, this study applies PLS(Partial Least Squares) to the survey collected from military personnel. The findings of our study may shed a light on improving the effectiveness of battlefield management information system.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.1
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• pp.90-113
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• 2021

Electronic Records Management System (ERMS) is a computer program or set of applications that is utilized for keeping up to date records along with their storage. ERMS has been extensively utilized for enhancing the performance of academic institutions. The system assists in the planning and decision-making processes, which in turn enhances the competencies. However, although ERMS is significant in supporting the process of decision-making, the majority of organizations have failed to take an initiative to implement it, taking into account that are some implementing it without an appropriate framework, and thus resulted in the practice which does not meet the accepted standard. Therefore, this study identifies the factors influencing the adoption of ERMS among employees of HLI in Yemen and the role of such adoption in the decision-making process, using the Unified Theory of Acceptance and Use of Technology (UTAUT) along with Technology, Organization and Environment (TOE) as the underpinning theories. The study conducts a cross-sectional survey with a questionnaire as the technique for data collection, distributed to 364 participants in various Yemeni public Higher Learning Institutions (HLI). Using AMOS as a statistical method, the findings revealed there are significant and positive relationships between technology factors (effort expectancy, performance expectancy, IT infrastructure and security), organizational factors (top management support, financial support, training, and policy),environmental factors (competitiveness pressure, facilitating conditions and trust) and behavioral intention to adopt ERMS, which in return has a significant relationship with the process of decision-making in HLI. The study also presents a variety of theoretical and empirical contributions that enrich the body of knowledge in the field of technology adoption and the electronic record's domain.

• International Journal of Computer Science & Network Security
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• v.21 no.3
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• pp.219-228
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• 2021

The adoption of new technology in any organization will represent change, and such change needs user acceptance for its successful implementation. Saudi Arabian health centers are no exception; therefore, the current study will investigate the adoption of new technology, namely that of virtual reality (VR), within health centers in Saudi Arabia and specifically in Riyadh City. This study explores the current state of VR technology adoption, factors that influence such adoption, and the extent of this technology's efficiency when it is used for vaccinating children. The data were collected from two samples: workers in vaccination clinics who responded to a survey and a group of children who participated in the VR technology experiment. The current study proposed a model based on the unified theory of acceptance and use of technology 2 (UTAUT2), with the addition of two variables: personal innovativeness and satisfaction. The results indicated that the respondents' perceptions regarding the health centers' infrastructure in terms of adopting VR were moderate. Among the factors affecting VR adoption, satisfaction, personal innovativeness, and behavioral intention were identified as vastly influential factors. From the eight hypotheses, six were found to be supported, with their factors significantly influencing behavioral intention with regard to VR technology adoption. Besides, the experiment concerning the use of VR technology on children verified the technique's high efficiency in terms of providing pain management and fear removal. These findings support the continuity of VR technology use, expand its future application fields, and integrate this study into the literature on technology acceptance models for VR adoption, as limited studies have covered this topic; consequently, this will benefit future research in this field.