• Transactions of the Korean Society of Mechanical Engineers A
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• v.21 no.6
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• pp.981-987
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• 1997

Modern helicopter rotor blades with non-homogeneous cross section composed of anisotropic material rquire highly sophisticated structural analysis. Variation in cross section geometry makes this task of analysis more complicated. Since rotor blades generally are much longer than their lateral dimensions, one-dimensional models seem feasible, at least from a computational point of view. Therefore determination of the principal coordinate system is very important to remove the structural coupling for one-dimensional beam modelling. In this study, shear center, and principal direction. The method will be verified by comparing the results with confirmed experimental results.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.17 no.6 s.123
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• pp.498-506
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• 2007

Using wind tunnel, experimental approaches were employed to investigate fluidelastic instability of tube bundles, subjected to uniform cross flow. There are several flow-induced vibration excitation mechanisms, such as fluidelastic instability, periodic wake shedding resonance, turbulence-induced excitation and acoustic resonance, which could cause excessive vibration in shell-and tube heat exchanges. Fluidelastic is the most important vibration excitation mechanism for heat exchanger tube bundles subjected to cross flow. The system comprised of cantilevered flexible cylinder(s) and rigid cylinders of normal square array, In order to see the characteristics of flow in tube bundles, particle image velocimetry was used. From a practical design point of view, Fluidelastic instability may be expressed simply in terms of dimensionless flow velocity and dimensionless mass-damping. The threshold flow velocity for dynamic instability of cylinder rows is evaluated and the data for design guideline is proposed for the tube bundles of normal square array.

• East Asian Economic Review
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• v.23 no.3
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• pp.227-260
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• 2019

This paper offers a comprehensive view of international risk sharing and of related policy issues from the perspective of the European Union. The traditional analyses contemplate three risk-sharing channels: the capital markets channel (through cross border portfolio investments), international transfers and the credit markets channel (via savings). Comparative analyses reveal that, on average, about 80% of the shock remains unsmoothed in Europe while only about 18% of the shock is transmitted to consumers within the US. From aggregated figures, there is space for improving, particularly, the cross-border investments channel in Europe. In this sense, the completion of the Banking and Capital Markets Union are expected to boost risk sharing across European member states. We also review new additional issues usually not contemplated by the traditional literature as depreciation, migration and the role of sovereigns and two new additional channels recently considered in the literature: government consumption and the real exchange rate. Finally, we also examine recent analysis related to the geographic distribution of risk sharing.

• Asia-Pacific Journal of Business
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• v.10 no.1
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• pp.13-23
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• 2019

Asian food and the Asian restaurant market have grown rapidly in the international market. It has become one of the major trends in the restaurant industry in the world. However, there has been little attempt to develop a scale for measuring customer's motivation to experience Asian restaurants, and cross-cultural approaches are very rare. From this point of view, this study examined an instrument to measure motivation to visit Asian restaurants developed by Jang and Kim (2015), which was originally developed based on UK customers, by applying the population from another cultural background, Thailand. A total of 308 valid responses were obtained in Thailand. CFA was performed with a Thai sample to test internal and external consistency of the scale with another population, and a comparison was made between UK and Thai customers.

• Korean Journal of Child Studies
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• v.26 no.5
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• pp.263-279
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• 2005

This study explored the participant roles and the cross-sectional and longitudinal relationships between interpersonal behavior characteristics and bullying/victimization. The subjects were 4th and 5th grade children and instruments were the Participant Roles Scale, Self-Report Coping Scale, Teenage Inventory of Social Skills, and Social Anxiety/Avoidance. They were contacted again one year later. In the distribution of participant roles at Time 1, defender of the victim was highest, then outsider; at Time 2 outsider was the highest and then defender. There was a tendency of gender difference in distribution of participant roles only at Time 1. Males were more in the group of reinforcer; females were more in the group of defender and victim. There were high positive correlations among bully/reinforcer/assistant scores. In the concurrent view, children who used approach coping strategies and showed higher social skills were more likely to be defender. Children who had lower social skills and higher social anxiety and social avoidance were more likely to be victim. In the longitudinal view, children who had developed higher social skills were more likely to be defender. Children who had employed less approach coping strategies and had showed lower social skills and higher social avoidance were more likely to be victim.

• Steel and Composite Structures
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• v.28 no.2
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• pp.179-194
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• 2018

Reliable and accurate method of computationally aided design processes of advanced thin walled structures in automotive industries are much essential for the efficient usage of smart materials, that possess higher energy absorption in dynamic compression loading. In this paper, most versatile components i.e., thin walled crash tubes with different geometrical profiles are introduced in view of mitigating the impact of varying cross section in crash behavior and energy absorption characteristics. Apart from the geometrical parameters such as length, diameter and thickness, the non-dimensionalized parameters of average forces which control the plastic bending moment for varying thickness has explored in view of quantifying its impact on the crashworthiness of the structure. The explicit finite element code ABAQUS is utilized to conduct the numerical studies to examine the effect of parametric modifications in crash behavior and energy absorption. Also the simulation results are experimentally validated. It is evident that the circular cross-sectional tubes are preferable as high collision impact shock absorbers due to their ability in withstanding axial and oblique impact loads effectively. Furthermore, the specific energy absorption (SEA), crash force efficiency (CFE), plastic bending moment, peak force responses and its impact for optimally tailoring a design to cater the crashworthiness requirements are investigated. The primary outcome of the study is to provide sufficient information on circular tubes for the use of energy absorbers where impact oblique loading is expected.

• Cross-Cultural Studies
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• v.27
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• pp.347-386
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• 2012

This article aims to establish the model of textual communication and its schema. To do this, we must identify the characteristics of textual communication, different from that of the oral, because the model of communication is usually done to show the structure of oral communication. Moreover, we must clarify the status text as '${\acute{e}}nonc{\acute{e}}$', that is to say product of the act of enunciation. The study of the text has now reached to achieve from the perspective of pragmatics, overcoming the structural point of view that dominates long text linguistics. And now, we need to enrich the theoretical basis of the pragmatics of text. Then the search of elements necessary to develop the model and pattern of textual communication can help to establish the elements used to form the theoretical basis. To clarify the characteristics of textual communication, we needed to explain the present communication by the position of reader and the point of view of textual reference. The schema that we proposed is not perfect, but there are still issues to think to complete it. For example, one must take into account the plurality of readers and reflect the relationship between interpretive texts in this schema, etc. This kind of problem is not only required to complete the schema but also to strengthen the basis of the theory of textual communication and the pragmatics of text.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2006.11a
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• pp.248-252
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• 2006

This study is intended to understand the intrinsic attributes of the view from the apartment unit in consideration of the diverse and complex elements of the view. To this end, the Questionnaire survey was conducted to identify the tendency in the recognition by apartment dwellers. The Questionnaire survey was conducted for the apartment residents to identify their interest in and the general trend in their recognition of the view from the living rooms of their housing unit, where Questionnaire items regarding landscape elements, the distances to and location of the landscape elements, and floor locations were compiled on the basis of the results from the field survey in the previous study. Consequently, the following results have been derived. 1) Apartment residents recognize not only natural landscape elements but also artificial elements, and prefer natural elements to artificial ones. 2) It is also indicated that they recognize the distances to and locations of landscape elements and that the satisfaction for the distance and location varies depending on the type of the landscape elements. 3) Furthermore, the floor of each unit is shown to result in certain differences in the recognized landscape elements. The cross-analysis between the floor and satisfaction indicates that the higher the floor, the more satisfied the residents are with the view.

• Geophysics and Geophysical Exploration
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• v.4 no.4
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• pp.101-109
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• 2001

In order to develop a spatial information system that can efficiently manage various subsurface data and produce information in a proper form for a user, we established a database of the well cores and built 3-D shapes that visualize the subsurface objects such as wells, ore bodies, tunnels, and mine cavities. We also made analysis tools available for three-dimensional ore bodies constructed here, such as vertical cross-section generator and mass computing tool. This system was developed by coding Avenue, a scripting language incorporated in ArcView, which is a commercial GIS software. Using the system, it is expected that users can make fast and accurate analysis and interpretation through real-time queries and by contemplating various objects in 3-D perspective.

• Journal of Information Display
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• v.3 no.3
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• pp.1-11
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• 2002

Multi-view function is important to three-dimensional displays without dedicated glasses. It is the reason that the observers earnestly desire to change their positions freely. Multi-viewing is also principal to the reality of three-dimensional (3D) image displayed on the screen. The display of projection type has the advantage that the number of viewing points can be easily increased according to the number of projectors. The authors research on multi-view projection display with hologram screen. Powerful directionality of the diffracted beam from hologram screen is required unlike two-dimensional (2D) display. We developed a new method that all diffracted beams satisfied the same Bragg condition and became sufficiently bright to observe the 3D image under usual indoor light. The principle is based on the essential Bragg diffraction in the three-dimensional space. Owing to such three-dimensional Bragg diffraction we achieved an excellent hologram screen that could be multiple reconstructed in spite of single recording. This hologram screen is able to answer arbitrary numbers of viewing points within wide viewing zone. The distortion of 3D image becomes also sufficiently small with the method of dividing the cross angle between illumination and diffraction beam.