• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2019.05a
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• pp.19-21
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• 2019

In this paper, we introduce VDES system and multipath channel model for maritime wireless digital communication. And we studied the influence of multipath for bit-error ratio performance by computer simulation. Next we propose time-domain adaptive equalizer to treat the influence of multipath, and review the simulation result for necessity of applying the adaptive equalizer.

• Asia pacific journal of information systems
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• v.32 no.4
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• pp.857-889
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• 2022

Home theft and burglary are prevalent in Dhaka city. Internet of things (IoT), in contrast, is commonly recognized as among the most advanced home security systems. However, the factors that attract young people to use IoT for household security have yet to be examined. Consequently, the purpose of this article is to validate the attitude-social influence-self-efficacy (ASE) model with personal innovativeness and perceived trust. We collected data from Dhaka citizens aged 15 to 24 using a purposive sample technique and 370 valid responses were chosen for the study. According to the analysis, all of our proposed hypotheses were found significant with a 73.6% variance. Furthermore, the effects of attitude and social influence were shown to be the highest and lowest, respectively, and trust and innovativeness were both nearly strong main predictors of ASE. Significantly, since this is one of the few studies in the technology adoption domain using this model, a solid foundation for IoT adoption for security purposes is established.

• Transactions of the Korean Society of Mechanical Engineers
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• v.12 no.4
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• pp.721-729
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• 1988

Recently, the precision required by precision manufacturing and machinery related to electronics is within the domain of submicron that it is difficult to evaluate them by traditional measuring equipments and methods. Accordingly, precision of sub 0.1.mu.m super precise position-decision-apparatus and straight-guide air bearing have been researched and they are almost ready to be used. In utilizing straight-guide-table for super-precision-measurement which used externally pressurized porous air bearing as a way of externally pressurized air bearing, the high-precision-straight movement is the most crucial. In this study, the researcher conducted the experimental study with trial manufacture to see how the surrounding temperature and support condition influenced the selection and allocation of the machine composing element which is important to the high-precision-straight movement. The researcher finding showed that when the property of the rail part and support part of the semi-closed slider form is different, the heat generation of the working motor and surrounding temperature influence the high-precision-straight movement significantly and the researcher showed the influence of the condition of central load and eccentric load to the straight movement precision when the support stand of the straight-table was supported by numerical values.

• Smart Structures and Systems
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• v.3 no.4
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• pp.405-422
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• 2007

A new hybrid damping technique for vibration reduction in flexible structures, wherein a combination of layers of hard passive damping alloys and active (smart) magnetostrictive material is used to reduce vibrations, is proposed. While most conventional vibration control treatments are based exclusively on either passive or active based systems, this technique aims to combine the advantages of these systems and simultaneously, to overcome the inherent disadvantages in the individual systems. Two types of combined damping systems are idealized and studied here, viz., the Noninteractive system and the Interactive system. Frequency domain studies are carried out to investigate their performance. Finite element simulations using previously developed smart beam elements are carried out on typical metallic and laminated composite cantilever beams treated with hybrid damping. The influence of various parameters like excitation levels, frequency (mode) and control gain on the damping performance is investigated. It is shown that the proposed system could be used effectively to dampen the structural vibration over a wide frequency range. The interaction between the active and passive damping layers is brought out by a comparative study of the combined systems. Illustrative comparisons with 'only passive' and 'only active' damping schemes are also made. The influence and the mode dependence of control gain in a hybrid system is clearly illustrated. This study also demonstrates the significance and the exploitation of strain dependency of passive damping on the overall damping of the hybrid system. Further, the influence of the depthwise location of damping layers in laminated structures is also investigated.

• Journal of the Korean Society of Earth Science Education
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• v.6 no.2
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• pp.112-123
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• 2013

Under this research, the survey is made on the definitive influence of the first-year education process of the science focus school for each of humanities, science and science core courses and the level of satisfaction of the non-curriculum experiment activity program for each course to find out the effectiveness of the first-year education process of the science focus school. For this purpose, this research has set three research issues. First, By clarifying the research result through the first-year education curriculum for science core school, noticeable change was observed for science focus school students through the change of attitude related to science for each desired course of students. Second, in the self-directed learning characteristics change, there was meaningful change for each desired field of students. Students hoping for humanities curriculum had great help in improvement of creative thinking for openness, creativeness and the like, but the influence was slightly insufficient in the moderation and control capability on themselves in learning attitude. Third, By analyzing the research result comprehensively, the first-year education curriculum for science core school provides high level of tailored science learning for the science focus school students and the level of satisfaction for students was significantly high.

• Structural Engineering and Mechanics
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• v.77 no.1
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• pp.57-74
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• 2021

The thermal eigenvalue responses of the graded sandwich shell structure are evaluated numerically under the variable thermal loadings considering the temperature-dependent properties. The polynomial type rule-based sandwich panel model is derived using higher-order type kinematics considering the shear deformation in the framework of the equivalent single-layer theory. The frequency values are computed through an own home-made computer code (MATLAB environment) prepared using the finite element type higher-order formulation. The sandwich face-sheets and the metal core are discretized via isoparametric quadrilateral Lagrangian element. The model convergence is checked by solving the similar type published numerical examples in the open domain and extended for the comparison of natural frequencies to have the final confirmation of the model accuracy. Also, the influence of each variable structural parameter, i.e. the curvature ratios, core-face thickness ratios, end-support conditions, the power-law indices and sandwich types (symmetrical and unsymmetrical) on the thermal frequencies of FG sandwich curved shell panel model. The solutions are helping to bring out the necessary influence of one or more parameters on the frequencies. The effects of individual and the combined parameters as well as the temperature profiles (uniform, linear and nonlinear) are examined through several numerical examples, which affect the structural strength/stiffness values. The present study may help in designing the future graded structures which are under the influence of the variable temperature loading.

• The Research Journal of the Costume Culture
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• v.31 no.3
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• pp.346-360
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• 2023

The pataphysics implemented by digital technology differs from the form of objects in the real world and is used throughout the cultural industry. This study aims to analyze the expression method of pataphysics as applied to modern fashion and derive its impact on the fashion industry. The research analyzes fashion images, shows, films, displays, and e-commerce, since 2016, when pataphysics began to be used in the fashion domain. Pataphysics, created by Alfred Zaire, appeared as an overlapping phenomenon that reflects physical phenomena in the virtual world. The expression method of pataphysics applied to modern fashion was divided into an augmented reality method based on immersion and interaction, a virtual platform-oriented metaverse, and a virtual model expressing a processed self. The influence of pataphysics applied to modern fashion is as follows. In the field of design, pataphysics affects the development of contemplative designs for innovation and creativity. Second, digital technology can expand the role of fashion at the intersection of art and fashion that takes a novel perspective through pataphysics. Third, e-commerce positively affects efficient production and consumption through virtual and economic models. In conclusion, this study's findings are expected to play a positive role in promoting creativity and innovation by introducing new perspectives and ideas into modern fashion through pataphysics.

• Journal of the Korea Institute of Building Construction
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• v.23 no.6
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• pp.751-760
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• 2023

Enhancing productivity in earthwork projects is crucial, significantly affecting both time and cost efficiencies. However, existing research in this domain predominantly relies on qualitative data and methodologies, which may not suffice given its critical significance. This study employed the fuzzy DEMATEL method to conduct a structural analysis of variables affecting productivity in construction projects. The findings reveal that plan changes possess the most substantial overall influence on earthwork productivity, with a comprehensive strength rating of 4.58. Additionally, it was observed that precipitation data exerted the most pronounced positive impact, with a rating of 0.48. These insights are anticipated to aid in identifying and prioritizing areas for productivity enhancement in construction projects.

• Asia pacific journal of information systems
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• v.33 no.3
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• pp.624-651
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• 2023

The study makes several contributions to not only the adoption literature by examining the influence of Emotional Intelligence (EI) and Big-Five traits on adoption of Augmented Reality (AR) but also given its utility in both industry and research, it contributes to the interesting inter-disciplinary domain of psychology, information systems, and human behaviour. A quantitative based approach using a sample of 275 respondents was undertaken. It is found that emotional intelligence influence both perceived ease-of-use and perceived usefulness. They in turn influence intention to use. Another important observation is that personality traits (openness and agreeableness) have a significant moderating effect on the relation between attitude and intention to use AR. This research will help academicians and executives working on the adoption of AR in various sectors ranging from retail industry to the education sector. The originality of this study is that it explores the impact of EI on the acceptance of AR and helps in extending the literature in interdisciplinary research.

• Korean Journal of Applied Biomechanics
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• v.25 no.1
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• pp.85-94
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• 2015

Purpose : The purpose of this study was to investigate the influence on the ground reaction force parameters according to wearing positions of backpack for during stair ascending and descending. Methods : Participants selected as subject were consisted of young female(n=10) and performed stairs walks(ascending and descending) with 2 types of wearing position(front of trunk[FT], rear of trunk[RT]). Passive(Fz 1) and active(Fz 2) forces of the vertical GRF were determined from time function and frequency domain. Also shear forces(Fx, Fy 1, Fy 2), dynamic postural stability index(MLSI, APSI, VSI, DPSI), loading rate and center of pressure (${\Delta}COPx$, ${\Delta}COPy$, COP area) were calculated from time function and frequency domain. Results : Fx, Fy 1, Fy 2, and Fz 1 in GRF didn't show significant differences statistically according to the wearing positions of backpack(p>.05), but stair descending showed higher forces than that of stair ascending. Particularly, Fz 2 of stair ascending showed higher forces than that of stair descending(p<.001), RT types showed higher than that of FT types(p<.05). MLSI, APSI, VSI, and DPSI of stair descending showed the increased stability index than that of stair ascending(p<.05), MLSI of RT types showed the decreased stability index than that of FT types(p<.05). Loading rate didn't show significant differences statistically according to the wearing positions of backpack(p>.05), but stair descending showed higher loading rate than that of stair ascending(p<.001). Also, ${\Delta}COPx$ in stair descending showed the increased movement than that of stair ascending(p<.05). Conclusions : A backpack of 10 kg(10 kg(ratio of body weights $17.61{\pm}1.17%$) showed significantly change GRF parameters according to wearing positions during stair ascending and descending. If possible, we suggest that the dynamic stability, in case of stairs walking with a smaller weights can be further improved.