• Proceedings of the Korean Magnestics Society Conference
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• 2011.06a
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• pp.86-86
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• 2011

• Proceedings of the Korean Magnestics Society Conference
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• 2013.12a
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• pp.108-109
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• 2013

• Proceedings of the Korean Magnestics Society Conference
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• 2014.11a
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• pp.35-36
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• 2014

• Proceedings of the Korean Magnestics Society Conference
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• 2008.12a
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• pp.68.2-68.2
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• 2008

• Wind and Structures
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• v.26 no.3
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• pp.179-190
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• 2018

Translation of tornadoes is an important feature in replicating the near-ground tornado flow field which has been simulated in previous studies based on Ward-type tornado simulators using relative motion of the ground plane. In this laboratory investigation, effects of translation on the near-ground tornado flow field were studied using the ISU Tornado Simulator that can physically translate over a ground plane. Two translation speeds, 0.15 m/s and 0.50 m/s, that scale up to those corresponding to slowly-moving tornadoes in the field were selected for this study. Compared with the flow field of a stationary tornado, the simulated tornado with translation had an influence on the spatial distribution and magnitude of the horizontal velocities, early reversal of the radial inflow, and expansion of the core radius. Maximum horizontal velocities were observed to occur behind the center of the translating tornado and on the right side of its mean path. An increase in translation speed, resulted in reduction of maximum horizontal velocities at all heights. Comparison of the results with previous studies that used relative motion of the ground plane for simulating translating tornadoes, showed that translation has similar effects on the flow field at smaller radial distances (~2 core radius), but different effects at larger radial distances (~4 core radius). Further, it showed that the effect of translation on velocity profiles is noticeable at and above an elevation of ~0.6 core radius, unlike those in studies based on the relative motion of the ground plane.

• Journal of Distribution Science
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• v.14 no.11
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• pp.5-17
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• 2016

Purpose - The purpose of this study is to establish an conceptual framework to explain the mechanism of internationalization behavior being used by recently established retailer in emerging countries. Research design, data, and methodology - The existing research on retail internationalization has focused on global retailers located in advanced countries which have expanded their business to emerging countries. That is, "internationalization from top to bottom". However, recent years have seen a reversal in this trend, resulting in the emergence of "internationalization from bottom to top" by retailers based in emerging economies. In order to explore this reversal, this study attempts to develop an conceptual framework based on the theories of "innovation" and "retail format". Results - This study found an conceptual framework which was adopted both a concept of "formula" derived from the theory of retail format and a concept of "production and process innovation" derived from the theory of innovation as a core concept. Conclusions - The conceptual framework provided an understanding of how retailers in emerging countries have gained a competitive advantage over retail companies based in countries with advanced economies. It suggested that innovation that gave these companies a competitive edge was caused by competitive interaction which allowed them to expand to oversea markets.

• Journal of Korean Society for Quality Management
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• v.46 no.2
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• pp.259-268
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• 2018

Purpose: SIT(Systematic Inventive Thinking) has been widely used in recent years. The validity of the five thinking tools of SIT is examined, and how to improve the inventive thinking tools is investigated. Methods: Frequency analysis on the usage of the TRIZ 40 inventive principles was used. Inventive thinking tools are derived by eliminating principles with low frequencies and grouping similar principles together. Results: Segmentation, prior action, combining, extraction, cushion in advance, transformation of properties are most frequently used among the 40 principles of TRIZ. The most frequently used principles and similar principles with them are grouped into new inventive thinking tools. Two of them, division and attribute dependency, belong to the 5 thinking tools of SIT, and the others, proactive measures, combination and reversal, do not. Conclusion: The newly identified inventive thinking tools are division, combination, proactive measures, attribute dependency, and reversal. The new five inventive thinking tools are quite efficient since they can cover more than two thirds of the TRIZ 40 inventive principles.

• Structural Engineering and Mechanics
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• v.46 no.6
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• pp.809-825
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• 2013

In the present study, in reinforced concrete structures, beam-column connections are one of the most critical regions in areas with seismic susceptibility. Proper anchorage of reinforcement is vital to enhance the performance of beam-column joints. Congestion of reinforcement and construction difficulties are reported frequently while using conventional reinforcement detailing in beam-column joints of reinforced concrete structures. An effort has been made to study and evaluate the performance of beam-column joints with joint detailing as per ACI-352 (mechanical anchorage), ACI-318 (conventional hooks bent) and IS-456(full anchorage conventional hooks bent) along with confinement as per IS-13920 and without confinement. Apart from finding solutions for these problems, significant improvements in seismic performance, ductility and strength were observed while using mechanical anchorage in combination with X-cross bars for less seismic prone areas and X-cross bar plus hair clip joint reinforcement for higher seismic prone areas. To evaluate the performances of these types of anchorages and joint details, the specimens were assembled into four groups, each group having three specimens have been tested under reversal loading and the results are presented in this paper.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.19 no.4 s.74
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• pp.347-356
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• 2006

In this paper, practical nonlinear inelastic analysis method of 3-dimensional steel structures accounting for gradual yielding with fibers on a section is developed. Geometric nonlinearities of member(p-$\delta$) and frame(p-$\Delta$) are accounted for by using stability functions. Residual stresses are considered by assigning initial stresses to the fiber on the section. The elastic core in a section is investigated at every loading step to determine the axial and bending stiffness reduction. The strain reversal effect is captured by investigating the stress change of each fiber. The proposed analysis proves to be useful in applying for practical analysis and design of three-dimensional steel frames.

• Nuclear Engineering and Technology
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• v.49 no.5
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• pp.953-967
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• 2017

In this paper, a complete station blackout (SBO) or complete loss of electrical power supplies is simulated and analyzed in a downward cooling 5-MW pool-type Material Testing Reactor (MTR). The scenario is traced in the absence of active cooling systems and operators. The code nodalization is successfully benchmarked against experimental data of the reactor's operating parameters. The passive heat removal system includes downward water cooling after pump breakdown by the force of gravity (where the coolant streams down to the unfilled portion of the holdup tank), safety flapper opening, flow reversal from a downward to an upward cooling direction, and then the upward free convection heat removal throughout the flapper safety valve, lower plenum, and fuel assemblies. Both short-term and long-term natural core cooling conditions are simulated and investigated using the RELAP5 code. Short-term analyses focus on the safety flapper valve operation and flow reversal mode. Long-term analyses include simulation of both complete SBO and long-term operation of the free convection mode. Results are promising for pool-type MTRs because this allows operators to investigate RELAP code abilities for MTR thermal-hydraulic simulations without any oscillation; moreover, the Tehran Research Reactor is conservatively safe against the complete SBO and long-term free convection operation.