• Journal of Industrial Technology
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• v.22 no.A
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• pp.137-144
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• 2002

A series of wind tunnel tests was conducted to investigate the existence of the galloping instability of inclined dry cables and also to Identify the influence of some parameters on it. These parameters are the structural damping and cable surface roughness, which may have significant impact on the vibration characteristics. The test results showed both the divergent type of galloping instability and the limited amplitude high wind speed vortex shedding excitation. Galloping instability was observed in only one case. Parametric study shows that the vortex shedding oscillation can be easily suppressed with an increase of structural damping. It was also shown that the instability criterion indicated by earlier research was too conservative compared to the results obtained from the present study.

• Journal of the Korean Society of Safety
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• v.29 no.3
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• pp.14-19
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• 2014

The global demand for reduction in the weight of automobiles has led many countries to focus on the development of hybrid, eco-friendly, and electric cars. Reduction in the weight of materials can both increase fuel efficiency and maximize automobile performance. Therefore, the design of automobile should be inclined towards the safety aspects. but at the same time, it also consider reducing the structural weight of an automobile. In this study, CFRP side members with circular and double hat shaped section was manufactured. The impact collapse tests performed with change of the stacking condition, such as variation of interface number and outerlayer angle. The impact collapse load and absorbed energy were quantitatively analyzed according to the changes in section shapes and stacking condition. This analysis was performed to obtain design data that can be applied in the development of optimum lightweight members for automobiles.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.12
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• pp.8408-8415
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• 2015

The purpose of this study is to propose and analyse new technology of structural elements design for Korean-style house(Hanok). Design of modern apartment building adopts many aesthetic elements from Hanok, however, these are only for the decorations of interior. In this study, projected Hanok eaves were studied in terms of the length of solar insolation. Inclined front slab system has been proposed utilizing sloping roof to an apartment building section. This system can provide the same sunshine radiation length and outside view to all levels of building to overcome the limitation of traditional hanok. It also can be applied to all residences the vertical garden concept of hanok. Inclined slab system showed 20% more efficient than flat slab system in terms of solar insolation length. This study also suggested a double deck slab system for not only reducing apartment floor impact noise but also connecting concept of traditional maru system in hanok. Double deck system reduces 66% of floor impact noise comparing with single deck slab of modern apartment buildings.

• Journal of Distribution Science
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• v.18 no.3
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• pp.67-76
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• 2020

Purpose: Consumers are affected by the purchase of a large number of opinions or support during the online purchasing process. This can be defined as the term of 'social decisions' on line. This paper seeks to explore the factors of influence on social decisions in on-line environment and to study in depth. Methodology: The purpose of this paper is to empirically examine the impact of factors on online social decisions. To verify the hypothesis of study, This study collected 256 from Seoul City, Gyeonggi Province and Chungcheong Province through Survey. Results: According to the research results, First, eWOM information usefulness have a positive impact on online social decisions, Second, online network connectedness have a positive impact on online social decisions. Third, innovative product have a positive impact on online social decisions. and the lower the category of knowledge, the more inclined it is to make online social decisions. Finally, social decisions have a positive impact on purchasing decisions about product. It is most significant that academic research has advanced consumer behavior in response to recent changes in the consumption environment. It is meaningful that we have studied in depth the changing consumer decision process in online channel environment.

• Journal of the Society of Naval Architects of Korea
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• v.47 no.2
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• pp.132-140
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• 2010

The very erosive cavitation is simulated by an inclined propeller dynamometer in the medium-size cavitation tunnel of MOERI. The inclined shaft for propeller makes strong cavitaion, which occurs around the root of a propeller blade. The cavitation begins at the leading edge of the propeller and contracted toward the trailing edge through the reentrant jet action. The cavity focused on the region near the trailing edge collapsed over the blade surface. As the impact pressure by the cavitation collapsing is too strong, it can damage the blade surface in the form of pit. This cavitation impacts created by the collapsing process are similar to the full-scale ones and are different from those by other erosion test methods. The newly developed cavitation erosion test method can be applied to evaluate the materials such as metals, ceramics and coatings in terms of cavitation resistance.

• Resources Recycling
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• v.5 no.3
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• pp.37-43
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• 1996

The recovery of metals from printed circuit board(PCBs) scraps was investigated by utilizing a shape sorting method.After all electronic parts mounted on the board were removed. PCBs were pulverized to particles smaller than 1 mm by aswing hammer type impact mill in order to liberate metal components. Metals were separated from nonmetalliccomponents by an inclined vibrating plate (IVP). The metal separation efficiency was measured as a function of vihrationintensity and inclined angle. The maximum efficiency was obtained when IVP was operated at the vibration intensity(Kv)of 1.40 and the inclined angle of 10". The grade of the metal components was recovered from PCBs exceeding 90% byusing IVP.0% by using IVP.

• Journal of Auto-vehicle Safety Association
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• v.15 no.4
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• pp.48-57
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• 2023

With the advance of autonomous vehicle technology various sitting posture is possible like relax position (inclined seating posture). Parametric study was done with MADYMO, a mutibody dynamics solver, to investigate the effect of sitting posture in different frontal crash modes, full frontal, 40% offset, and angled rigid barrier crash as well as various impact speeds. Hybrid III 50th male and 5th female dummies were used to figure out the difference induced by occupant weight and dimension. Restraint system parameters complying to current safety protocols like NCAP are studied if they still work effectively in relax position which is feasible with autonomous vehicles.

• Structural Engineering and Mechanics
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• v.18 no.4
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• pp.389-410
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• 2004

In this study, theoretical and experimental results are presented which were obtained during an investigation of the influence of the $P-{\Delta}$ effect that was caused by the simultaneous changing of the axial load P of the column and the lateral displacement ${\Delta}$ in the external beam-column joints. The increase or decrease of ${\Delta}$ was simultaneous with the increase or decrease of the axial compression load P and caused an additional influence on the aseismic mechanical properties of the joint. A total of 12 reinforced concrete exterior beam-column subassemblies were examined. A new model, which predicts the beam-column joint ultimate shear strength, was used in order to predict the seismic behaviour of beam-column joints subjected to earthquake-type loading plus variable axial load and $P-{\Delta}$ effect. Test data and analytical research demonstrated that axial load changes and $P-{\Delta}$ effect during an earthquake cause significant deterioration in the earthquake-resistance of these structural elements. It was demonstrated that inclined bars in the joint region were effective for reducing the unfavourable impact of the $P-{\Delta}$ effect and axial load changes in these structural elements.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.1149-1155
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• 2007

The transition area between a bridge and an earthwork is one of the weakest area of track because of the track geometry deterioration caused unequal settlement of backfill of abutment. In case of a ballastless track, the approach slab is installed to prevent the phenomenon. But, if there is occurred the inclined displacement on the approach slab by a settlement of the foundation or formation, the track is also under the inclined displacement. And this defect causes reducing the running stability of a vehicle, the riding comfort of passengers, and the deteriorations of track by excessive impact subjected to the track. In this study, parametric studies were performed to know what is the allowable displacement limit on the approach slab to avoid such a bad effect. The length and amount of unequal settlement of the approach slab was adopted as parameter for numerical analysis. And car body accelerations, variations of wheel force and rail stress and uplift force induced on a fastener clip are investigated. From the result, resonable settlement limits of an approach slab according to slab length was suggested.

• Advances in nano research
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• v.16 no.4
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• pp.427-434
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• 2024

Latest advancement in field of fluid dynamics has taken nanofluid under consideration which shows large thermal conductance and enlarges property of heat transformation in fluids. Motivated by this, the key aim of the current investigation scrutinizes the influence of thermal radiation and magnetohydrodynamic on the laminar flow of an incompressible two-dimensional Williamson nanofluid over an inclined surface in the presence of motile microorganism. In addition, the impact of heat absorption/generation and Arrhenius activation energy is also examined. A mathematical modeled is developed which stimulate the physical flow problem. By using the compatible similarities, we transfer the governing PDEs into ODEs. The analytic approach based on Homotopy analysis method is introduced to impose the analytic solution by using Mathematica software. The impacts of distinct pertinent variable on velocity profiles are investigated through graphs.