• Earthquakes and Structures
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• v.15 no.2
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• pp.155-164
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• 2018

Design of structures subjected to blast loads are usually carried out through nonlinear inelastic dynamic analysis followed by imposing acceptance criteria specified in design codes. In addition to comprehensive aspects of inelastic dynamic analyses, particularly in analysis and design of structures subjected to transient loads, they inherently suffer from convergence and computational cost problems. In this research, a strategy is proposed for design of steel moment resisting frames under far range blast loads. This strategy is inspired from performance based seismic design concepts, which is here developed to blast design. For this purpose, an algorithm is presented to calculate the capacity modification factors of frame members in order to simplify design of these structures subjected to blast loading. The present method provides a simplified design procedure in which the linear dynamic analysis is preformed, instead of the time-consuming nonlinear dynamic analysis. Nonlinear and linear analyses are accomplished in order to establish this design procedure, and consequently the final design procedure is proposed as a strategy requiring only linear structural analysis, while acceptance criteria of nonlinear analysis is implicitly satisfied.

• Korean Journal of Computational Design and Engineering
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• v.5 no.2
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• pp.184-195
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• 2000

MDO (Multidisciplinary Design Optimization) methodology is an emerging new technology to solve a complicate structural analysis and design problem with a large number of design variables and constraints. In this paper MDO methodology is adopted through the use of computer aided systems such as Geometric Solid Modeller, Mesh Generator, CAD system and CAE system. And this paper introduces MDO methodology as a new method for structural analysis and design through the application to the structural design of flap drive system. In a MDO methodology application to the structural design of flap drive system, kinetodynamic analysis is done using a simple aerodynamic analysis model for the air flow over the flap surface instead of difficult aerodynamic analysis. Simultaneously the structural static analysis is done to obtain the optimum structural condition. And the structural buckling analysis for push pull rod is also done to confirm the optimum structural condition (optimum cross section shape of push pull rod).

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2006.05a
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• pp.180-183
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• 2006

The recognition of emotionality becomes so important that it is called 'emotional consumption society'. The emotional design, which is mostly concerned about users consensus and experiences, is understood from a interactive point of view, human, and space. Today, the emotional design is a new paradigm. From this point of view, this paper, which presents patterns analysis of outdoor lighting by the emotional design, applies expression techniques of the emotional design in Analysis process of outdoor lighting patterns. Also, this paper shows examples at analysis process.

• The KSFM Journal of Fluid Machinery
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• v.15 no.6
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• pp.11-17
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• 2012

The one way fluid structure interaction analysis on advanced propeller blade for next generation turboprop aircraft. HS1 airfoil series are selected as a advanced propeller blade airfoil. Adkins method is used for aerodynamic design and performance analysis with respect to the design point. Adkins method is based on the vortex-blade element theory which design the propeller to satisfy the condition for minimum energy loss. propeller geometry is generated by varying chord length and pitch angle at design point. Blade sweep is designed based on the design mach number and target propulsion efficiency. The aerodynamic characteristics of the designed Advanced propeller were verified by CFD(Computational Fluid Dynamic) and showed the enhanced performance than the conventional propeller. The skin-foam sandwich structural type is adopted for blade. The high stiffness, strength carbon/epoxy composite material is used for the skin and PMI(Polymethacrylimide) is used for the foam. Aerodynamic load is calculated by computational fluid dynamics. Linear static stress analysis is performed by finite element analysis code MSC.NASTRAN in order to investigate the structural safety. The result of structural analysis showed that the design has sufficient structural safety. It was concluded that structural safety assessment should incorporate the off-design points.

• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.4
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• pp.179-185
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• 2008

The purpose of this paper is to propose a systematic method on the weld pitch design of a vehicle sub-frame considering the fatigue life of spot welding points. The input data, which perform the fatigue analysis on the spot welding nuggets, are obtained by both the dynamic analysis of the multi-body vehicle model passing through the virtual proving ground of a typical Belgian road and the quasi-static analysis with the finite element model of the vehicle sub-frame. By utilizing the life cycle data obtained from the fatigue analysis, the welding points to perform the pitch change are determined. The sensitivity analysis on the fatigue life of the welding points is carried out by using the three-level orthogonal array design, and through the results of the sensitivity analysis, the best combination on the welding pitch is determined. This study shows that as compared with the baseline design, the sub-frame redesigned by the proposed technique improves the fatigue life about 7 percent while reducing the number of welding points about 19 percent.

• 한국전산유체공학회:학술대회논문집
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• 2011.05a
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• pp.173-178
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• 2011

Nowadays, SELENE-2 is under development for the moon explorer rover in Japan. AXS(Active X-ray Spectrometer) sensor development among the candidated payloads will be on going by the world-wide co-operation. The thermal design, analysis and test will be specially performed by Korean institutes. CFD techniques are used for the conceptual design and analysis. Thin-shell plate meshes being applied by Monte-Carlo Ray Tracing Method are generated for the thermal radiation analysis. Lumped capacity model is employed for the thermal conduction simulation of the AXS payload itself. Various shapes of the payload configuration with thermal boundary conditions are proposed and selected on the purpose of the analysis of the initial design. The results of the analysis are supposed to be used as the baseline for the further detailed design of the AXS payload in the future.

• Journal of KSNVE
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• v.5 no.3
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• pp.395-402
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• 1995

In general low frequency vibration characteristics like an idleshake is mainly influeced by pillar section properties and joints. So the design technique development of vehicle pillar structures is required to initial design and vehicle development stage. In this paper to develop pillar structure design technique considering low frequency vibration characteristics, strain energy method, design sensitivity analysis method, and design optimization method using commercial finite element analysis program and optimization program are presented.

• Fashion & Textile Research Journal
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• v.12 no.5
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• pp.555-563
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• 2010

This research has attempted for a categorization by contemplating on concepts and characteristics of eco fashion design through analysis of precedent studies and to study the design characteristics, images, and internal values through keyword and design codes which appeared in the precedent studies. The subject of analysis was mostly focused on the theses published in international and domestic academic journals from 1990s to September 2009. The design characteristics of each eco fashion design were analyzed by classifying by form, detail, color, fabric and pattern. Method of analysis did content analysis. The results of the research can be summarized as follows. First of all, types of eco fashion design were human-ecology design, natural-ecology design, and social-ecology design. Secondly, the human-ecology design was presented a natural and comfortable form, color of the nature, and functional and new materials. The natural-ecology design was presented a natural silhouette, natural colors, and natural fiber. The social-ecology design were used a loose silhouette and over-size forms, natural colors, and recycled materials and bio fabric. Thirdly, the images per type of eco fashion design were Zen, sportive, natural, and modern image. And the internal values were presented efficiency, health-orientation, naturalness, and continuity.

• Journal of Digital Convergence
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• v.17 no.7
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• pp.125-130
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• 2019

Sensitivity analysis is used to determine the effect of a change in a design parameter on the total system, and the calculated sensitivity is an important indicator of the improvement of a structure. In this study, we investigated the method of deriving and analyzing the sensitivity of design parameters by using finite element analysis and the method of improving a structure by using sensitivity analysis results. Design parameters for weight reduction design were selected using actual semiconductor inspection equipment that requires structural improvement, and the sensitivity to design parameters was calculated by using and finite difference method. We propose an improvement method that can reduce the weight while maintaining the transient response required by the equipment. By using the results of the sensitivity analysis through finite element analysis and finite difference method, we can create a structurally improved design that satisfies the desired stress or displacement by improving the design of the structure. Therefore, sensitivity analysis is applicable to various fields as well as semiconductor inspection equipment.

• International Journal of Aeronautical and Space Sciences
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• v.18 no.4
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• pp.662-674
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• 2017

This paper describes the multidisciplinary design optimization (MDO) process of a tailless unmanned combat aerial vehicle (UCAV) using global variable fidelity aerodynamic analysis. The developed tailless UAV design framework combines multiple disciplines that are based on low-fidelity and empirical analysis methods. An automated high-fidelity aerodynamic analysis is efficiently integrated into the MDO framework. Global variable fidelity modeling algorithm manages the use of the high-fidelity analysis to enhance the overall accuracy of the MDO by providing the initial sampling of the design space with iterative refinement of the approximation model in the neighborhood of the optimum solution. A design formulation was established considering a specific aerodynamic, stability and control design features of a tailless aircraft configuration with a UCAV specific mission profile. Design optimization problems with low-fidelity and variable fidelity analyses were successfully solved. The objective function improvement is 14.5% and 15.9% with low and variable fidelity optimization respectively. Results also indicate that low-fidelity analysis overestimates the value of lift-to-drag ratio by 3-5%, while the variable fidelity results are equal to the high-fidelity analysis results by algorithm definition.