• Journal of Auto-vehicle Safety Association
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• v.3 no.2
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• pp.11-16
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• 2011

In recent years, rapid-increasing market share of compact cars and SUVs has brought for both consumer and automaker to pay more attention on crash compatibility between the compact passenger vehicles and the light trucks (i.e., Pickups and SUVs). Vehicle compatibility regarding both self and partner protection in frontal crash of different class vehicles is one of hot issues in vehicle safety. Furthermore, it is expected that the amendment of UNECE-Regulation 94 to implement compatibility issues in couple of coming years. In this study, conceptual design of compatibility compliant frontal vehicle structure which subjects to improve? the distribution of frontal crash loading and structural engagement between vehicles is introduced. The effects of proposed vehicle structure on both possible candidates (i.e. FWRB, FWDB and PDB) for a compatibility evaluation test procedure and car-to-car crash are also investigated.

• Journal of the Korean Society for Railway
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• v.9 no.6 s.37
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• pp.635-643
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• 2006

In this paper, a theorectical approach is studied to predict structural performances and weight-reduction rates of hybrid bodyshells in case that the materials of roof structures are substituted. To determine other light-weight materials to be substituted for the original roof materials, bending and twisting deformations are considered under constant stiffness and strength conditions, which derive some new weight-reduction indices from a structural performance point of view. The indices derived to estimate the weight-reduction can be utilized as a good criterion at the conceptual design for material substitution of the roofs.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.8
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• pp.1623-1630
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• 2002

Recently, much attention is imposed on the design of the fuel assemblies in the Pressurized Light Water Reactor (PWR). Spacer grid is one of the main structural components in a fuel assembly. It supports fuel rods, guides cooling water, and maintains a coolable geometry from the external impact loads. In this research, a new shape of the spacer grid is designed by the axiomatic approach. The Independence axiom is utilized for the design. For conceptual design, functional requirements (FRs) are defined and corresponding design parameters (DPs) are found to satisfy FRs in sequence. Overall configuration and shapes are determined in this process. Detail design is carried out based on the result of the axiomatic design. For the detail design, the system performances are evaluated by using linear and nonlinear finite element analysis. The dimensions are determined by optimization. Some commercial codes are utilized for the analysis and design.

• Proceedings of the KSME Conference
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• 2001.06c
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• pp.548-553
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• 2001

Recently, much attention is imposed on the design of the fuel assemblies in the Pressurized Light Water Reactor (PWR). Spacer grid is one of the main structural components in a fuel assembly. It supports fuel rods, guides cooling water and protects the system from the external impact loads. Various space grids have been proposed and new designs are also being created. In this research, a new spacer grid is designed by the axiomatic approach. The Independence Axiom is utilized for the design. For conceptual design, functional requirements (FRs) are defined and corresponding design parameters (DPs) are found to satisfy FRs in sequence. Overall configuration and shapes are determined in this process. Detail design is carried out based on the result of the axiomatic design. For the detail design, the system performances are evaluated by using linear and nonlinear finite element analysis. The dimensions are determined by optimization. Some commercial codes are utilized for the analysis and design.

• Steel and Composite Structures
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• v.32 no.4
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• pp.479-495
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• 2019

In tied-arch bridges, the way the arch and the deck are connected may become crucial. The deck is usually suspended from hangers made out of steel pinned cables capable of resisting axial forces only. However, a proper structural response may be ensured by fixing and stiffening the hangers in order to resist, additionally, shear forces and bending moments. Thus, this paper studies the effect of different pinned and stiffened hanger arrangements on the structural behavior of the tied-arch bridges, with the intention of providing designers with useful tools at the early steps of design. Longitudinally and transversally stiffened hangers (and the effect of hinges at the hangers and their locations) are studied separately because the in-plane and the out-of-plane behavior of the bridge are uncoupled due to its symmetry. As a major conclusion, regarding the in-plane behavior, hangers composed of cables (either with vertical, $Nielsen-L\ddot{o}hse$ or network arrangements) are recommended due to its low cost and ease of erection. Alternatively, longitudinally stiffened hangers, fixed at both ends, can be used. Regarding the out-of-plane behavior, and in addition to three-dimensional arrangements of cables, of limited effectiveness, transversally stiffened hangers fixed at both ends are the most efficient arrangement. A configuration almost as efficient and, additionally, cheaper and easier to build can be achieved by locating a hinge at the end corresponding to the most flexible structural element (normally the arch). Its efficiency is further improved if the cross-section tapers from the fixed end to the pinned end.

• Wind and Structures
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• v.34 no.3
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• pp.291-301
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• 2022

Although mostly used in wind turbine market, single rotor wind turbines have problems with transportation and installation costs due to their large size. In order to solve such problems, multi-rotor wind turbine is being proposed; however, light weight design of multi-rotor wind turbine is required considering the installation at offshore or deep sea. This study proposes the systematic design process of the multi-rotor wind turbine focused on its supporting structure with simultaneous consideration of static and dynamic behaviors in an ideal situation. 2D and successive 3D topology optimization process based on the density method were applied to minimize the compliance of supporting structure. To realize the conceptual design obtained by topology optimization for manufacturing feasibility, the derived 3D structure was modified to have shell structures and optimized again through parametric design using the design of experiments and the response surface method for detail design of their thicknesses and radii. The resultant structure was determined to satisfy the stress and the buckling load constraint as well as to minimize the weight and the resultant supporting structure were verified numerically.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.35 no.2
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• pp.65-71
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• 2022

Recently, multi-material structural topology optimization is more critical because it provides reasonable solution to weight reduction challenges and can as well provide effective conceptual design. For conventional multi-material topology optimization (MMTO), the number of design variable increases when the number of candidate materials increases, and accordingly, a significant increase in computational time occurs. Therefore, MMTO with a single design variable, such as the phase section method (PSM) was proposed. This research is focused on improving the PSM, considering three major limitations: the composition ratio does not represent the area or volume ratio, design variables are not sufficiently concentrated to target values, and certain materials are created less than they are required. To address such limitations, the redefined composition ratio and adjusted parameters for better convergence are proposed. The validation of proposed modifications is verified via two- and three-dimensional numerical examples.

• Korean Institute of Interior Design Journal
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• v.19 no.2
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• pp.99-106
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• 2010

This study is about Foucault's conceptual and methodological relevance for structural analysis of Korean traditional space design history. By Foucault's Theory, regionalism is product of the instrumentality of space, power, knowledge and provide the basis for making the operation of power both spatial and temporal. The purpose of this study is to establish topographical map of historical progress and to shed new light on the forming of identity in Korean traditional space design on the poststructural-archaeological aspect. The process of this study is illustrated as follows: At first, it suggests Foucault's 'Theory of archaeology'. It mentions 'historical apriori' and archive, collateral space and general grammar as theoretical background of archaeological logic. Secondly, it clarifies 'statements' depending on the conditions that is 'episteme' in which they emerge and exist within a field of discourse. And it discuss Korean traditional space design concept as a social product on the situated character of interaction in time-space. Finally, it studies genetic variation process of Korean traditional space design based on the social progress in Korean society. And it analyses practical actions of 'Statements' in terms of general grammar and textuality.

• International Journal of High-Rise Buildings
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• v.3 no.4
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• pp.285-296
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• 2014

The objective of optimization is to present a design process that minimizes the total material consumption while satisfying current codes and specifications. In the research an optimization formulation for RC shear wall structures is proposed. And based on conceptual design methodology, an optimization process is investigated. Then optimal design techniques and specific explanations are introduced for residential buildings with shear wall structure, especially for that with a rectangular layout. An example of 30-story building is presented to illustrate the effectiveness of the proposed optimal design process. Furthermore, the influence of aspect ratio on the concrete consumption and the steel consumption of the superstructure are analyzed for this typical RC shear wall structure; and their relations are obtained by regressive analysis. Finally, the optimal material consumption is suggested for the residential building with RC shear wall structure and with rectangular layout. The relation and the data suggested can be used for guiding the design of similar RC shear wall structures.

• Journal of the Regional Association of Architectural Institute of Korea
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• v.21 no.5
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• pp.161-168
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• 2019

The use of various digital tools makes freeform modeling possible. At the same time, with the development of structural and construction technologies, Free-Form Architecture are beginning to be implemented realized, as the desired data extraction such as the size and coordinate points of the members is possible. Currently, in many cities around the world, Irregular-Shaped High-rise Buildings, which express the dynamic symbolism, are recognized for their landmark values. In order to realize the Irregular-Shaped High-rise Buildings, it is necessary to understand various fields such as the characteristics of digital tools, digital technique logic, design process, and construction method. In particular, it is important to plan Irregular-Shaped High-rise Buildings so that the various types of efficiency can be reviewed together, while generating understanding and formations from the initial design stage. Therefore, this study uses conceptual and parametric design tools related to form generation in digital architecture to analyze the details, methods, and characteristics of the Irregular-Shaped High-rise Buildings form generation process. In this paper, the parametric design tool is applied to study the various types of design and the process characteristics that can be considered in the initial design stage of the unstructured skyscraper.