• Journal of the Korean Crystal Growth and Crystal Technology
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• v.28 no.6
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• pp.271-276
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• 2018

Based on the service design processes, we examined the market conditions and the criteria to be considered in selecting materials and selected CFRP CNT materials in the development of bicycle design. This material was used to develop frame design among the bicycle parts. The bicycle frame, designed with CFRP CNT material through vibration attenuation testing, tensile strength testing, and stiffness test results before prototype production, shows better results than the bicycle frame manufactured with conventional CNT materials in terms of function.

• Journal of the Korea Institute of Building Construction
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• v.12 no.3
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• pp.347-357
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• 2012

While it is generally possible to install curved panels manufactured in a factory within the permitted error range on an irregular surface frame of concrete or steel, it is difficult and expensive. Freeform architecture is thus designed and constructed differently from formal buildings. In order to more easily and inexpensively actualize freeform architecture, Building Information Modeling (hereinafter referred to as BIM) has recently been applied in the construction industry. However, the related research and case analyses are not sufficient to identify the implications and contributions of freeform buildings in future similar projects. Therefore, this research will study design and construction methods for freeform surfaces, particular the concrete surface frame of freeform buildings based on BIM, focused on the Tri-Bowl project. This study attempts to analyze the pros and cons of each method for the concrete surface frame of the Tri-Bowl, and then presents the lessons learned and implications related to the design and construction process of the freeform architecture. Several implications for design and construction of concrete surface frame of the freeform building, the Tri-Bowl, are found. The first is that manufacturing and installation of a curved concrete frame is precisely performed based on the exact numerical values of materials and installation made using BIM 3D technologies, such as CATIA and Rhino. The second is that close and continuous collaboration among the different participants in the construction of the Tri-Bowl allowed them to cope with virtual conditions. The third is that design and construction processes have changed, and high quality of the surface frame of a freeform building is required.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.3
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• pp.353-359
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• 2010

For achieving economical fuel consumption, an increase in the load bearing capacity, and for environmental conservation, there is a constant demand for lightweight frames of commercial vehicles used in the transportation industry. In this study, a structural analysis of the frame of a heavy flat-bed trailer was performed to determine the optimal design of a new lightweight frame made of high-strength steel. To identify the key design parameters of the trailer frame, Taguchi's orthogonal array was used in the experiments. Using ANSYS, a commercial FEA program, the frame structure was optimized with respect to stress, deflection, and torsional stiffness by performing stress and vibration analyses. A physical model of the trailer was also built to verify the validity of the numerical analyses. Finally, an on-road fatigue test of the new lightweight frame made of the high-strength steel, ATOS80, was performed to confirm the durability of the new design.

• Structural Engineering and Mechanics
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• v.78 no.4
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• pp.485-496
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• 2021

So far analytical methods on collapse assessment of three-dimensional (3-D) steel frames have mainly focused on a single-column-removal scenario. However, the collapse of the Federal Building in the US due to car bomb explosion indicated that the loss of multiple columns may occur in the real structures, wherein the structures are more vulnerable to collapse. Meanwhile, the General Services Administration (GSA) in the US suggested that the removal of side columns of the structure has a great possibility to cause collapse. Therefore, this paper analytically deals with the robustness of 3-D steel frames in a two-side-column-removal (TSCR) scenario. Analytical method is first proposed to determine the collapse resistance of the frame during this column-removal procedure. The reliability of the analytical method is verified by the finite element results. Moreover, a design-based methodology is proposed to quickly assess the robustness of the frame due to a TSCR scenario. It is found the analytical method can reasonably predict the resistance-displacement relationship of the frame in the TSCR scenario, with an error generally less than 10%. The parametric numerical analyses suggest that the slab thickness mainly affects the plastic bearing capacity of the frame. The rebar diameter mainly affects the capacity of the frame at large displacement. However, the steel beam section height affects both the plastic and ultimate bearing capacity of the frame. A case study on a six-storey steel frame shows that the design-based methodology provides a conservative prediction on the robustness of the frame.

• Geomechanics and Engineering
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• v.22 no.3
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• pp.265-275
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• 2020

As a flexible supporting structure, the anchoring frame structure is widely adopted to support multistage slopes in high earthquake-intensity area for its effectiveness and practicality. The previous study indicates that the anchor of anchoring frame structure is the most likely to be damaged during earthquakes. It is crucial to determine the pull-out capacity of anchor against seismic force for the seismic design of anchoring frame structure. In this study, an analytical model of a three-stage slope supported by anchoring frame structure is established, and the upper bound method of limit analysis is applied to deduce the seismic anchor force of anchoring frame structure. The pull-out capacity of anchor against seismic force of anchoring frame structure at each stage is obtained by computer programming. The proposed method is proved to be reasonable and effective compared with the existing published solution. Besides, the influence of main parameters on the pull-out capacity of anchor against seismic force is analyzed to provide some recommendations for the seismic design of anchoring frame structure.

• Journal of the Ergonomics Society of Korea
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• v.24 no.2
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• pp.1-8
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• 2005

A new design of shoulder straps and frame of backpack is proposed for reducing compression and fatigue of shoulder. The stress reduction effects of a backpack equipped with the newly designed shoulder straps and frame have been analyzed statistically through various experiments. We show that the newly designed shoulder straps(wider than the conventional ones) is superior to existing shoulder straps in respect of RPE, task performance measure and physiological measure. The new frame is also proven to be superior to existing frame in respect of RPE and task performance measure. In conclusion, the proposed shoulder straps and frame are shown to enhance the task performance of soldiers.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2006.04a
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• pp.873-880
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• 2006

Since the mega frame structure has significant numbers of elements and nodes, it takes tremendous times and computer memories to analyze and design the structures. Therefore, the exclusive structural analysis program for mega frame system is developed to reduce the efforts and time required for the analysis and design of mega frame structure. To this end, an efficient modelling technique using the characteristics of mega frame structures and an efficient analytical model, which uses a few DOFs selected by the user using the matrix condensation method. are developed in tins study. Static and dynamic analyses are conducted using an example structure.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.6
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• pp.961-967
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• 2012

The metal is frequently used in the air-conditioner frame, which must have the durability from the various external environments, but has difficulties in being manufactured for many complex shapes. On the other hand, the plastic, used as a material of injection molding, enables the realization of various shapes and the mass-production of complex ones and leads low production cost. As the air-conditioner frame becomes increasingly complex and detailed, the plastic material is highlighted as an alternative for the frame. But the product molded by plastic with a complex shape might have a noise problem. Therefore this study attempts to design the product through TRIZ in order to reduce the noise of the air-conditioner with the frame of plastic material.

• Structural Engineering and Mechanics
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• v.32 no.2
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• pp.321-335
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• 2009

When a roof frame is subjected to the airblast loading, the conventional way to analyze the damage of the frame or design the frame is to use single degree of freedom (SDOF) model. Although a roof frame consists of beams and girders, a typical SDOF analysis can be conducted only separately for each component. Thus, the rigid body motion of beams by deflections of supporting girders can not be easily considered. Neglecting the beam-girder interaction in the SDOF analysis may cause serious inaccuracies in the response values in both Pressure-Impulse curve (P-I) and Charge Weight-Standoff Diagrams (CWSD). In this paper, an inelastic two degrees of freedom (TDOF) model is developed, based on force equilibrium equations, to consider beam-girder interaction, and to assess if the modified SDOF analysis can be a reasonable design approach.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.8 s.185
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• pp.145-153
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• 2006

To minimize the possible leakage of microwave when one opens the door of a microwave oven during its operation, a structural design of the reinforcing brackets for the door frame is presented. Twisting deformation of the door frame resulting from a dynamic pulling force is analyzed by harmonic and transient response analyses. Several types of the reinforcing brackets weldable to the right flange of the door frame is taken into consideration, and their effects to the twisting deformation of the door frame are compared and evaluated. As a conclusion, a thick step-shaped bracket, which is welded to whole length of the right flange, is favorable.