• Korean Journal of Computational Design and Engineering
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• v.7 no.1
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• pp.34-41
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• 2002

Five-axis NC machining, in general, is utilized in fabricating impellers, turbine blades, marine propellers that can be machined more effectively rather than three-axis machining. There have been many researches concerning tool interference avoidance, optimization of tool orientation. The C-space or Configuration-space was originated from the robotics area, which depicts interference-free joint-values in motion planning. In the paper we propose an optimizing scheme by which the maximum effective-radius of a face-milling cutter can be achieved for each CC(cutter-contact) point. Also the concept of a C-space for a CC point, the effective-radius map for 5-axis face-milling, and some illustrative examples of marine propeller machining, are presented.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.11a
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• pp.83-84
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• 2014

The whole wall system behaves as one section because single walls composing irregular wall are connected to each other. Although stress of a single wall is affected to the connected wall under lateral load, the stress is not transferred to whole sections and is concentrated on particular part of the wall as well. Therefore these walls can be divided into the effective and ineffective section. The purpose of this study is to compare design result of irregular wall using codes and previous studies on an effective width of the wall and to analyze reduction of the longitudinal bar of irregular wall.

• Tribology and Lubricants
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• v.20 no.5
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• pp.231-236
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• 2004

Sulfur Hexafluoride, S $F_{6}$ is widely used for leak detection and as a gaseous dielectric in transformers, condensers and circuit breakers. S $F_{6}$ gas is also effective as a cleanser in the semiconductor industry. This paper presents a numerical study of the sealing force of disk type seal in S $F_{6}$ gas safety valve. The sealing force on the disk seal is analyzed by the FEM method based on the Taguch's experimental design technique. Disk seals in S $F_{6}$ gas safety valve are designed with 9 design models based on 3 different contact length, compressive ratio and gas pressure. The calculated results of Cauchy stress and strain showed that the sealing characteristics of Teflon $^{ }$PTFE is more effective compared to that of FKM(Viton), which is related to the stiffness of the materials. And also, the contact length of the disk seal is important design parameter for sealing the S $F_{6}$ gas leakage in the safety valve.afety valve.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2005.04a
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• pp.704-711
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• 2005

Recently Life Cycle Cost Analysis for civil infrastructures such as pavements, bridges, and dams has been emphasized However, so far, there are few systems available for life cycle cost analysis of bridges at design stage. Therefore, the objective of this paper is to develop a user-friendly life-cycle cost analysis system for LCC-effective optimal design decision making at design stage. The program is based on the proposed LCC model, formulation, analysis modules and systematic procedure that suit Korean construction conditions. It is expected that the developed system can be effectively utilized for more LCC-effective design of bridges. It is applied to an actual bridge design project in order to demonstrate its effectiveness and applicability.

• Computers and Concrete
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• v.20 no.2
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• pp.129-143
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• 2017

Seismic design of reinforced concrete (RC) structures requires a certain minimum level of flexural ductility. For example, Eurocode EN1998-1 directly specifies a minimum flexural ductility for RC beams, while Chinese code GB50011 limits the equivalent rectangular stress block depth ratio at peak resisting moment to achieve a certain nominal minimum flexural ductility indirectly. Although confinement is effective in improving the ductility of RC beams, most design codes do not provide any guidelines due to the lack of a suitable theory. In this study, the confinement for desirable flexural ductility performance of both normal- and high-strength concrete beams is evaluated based on a rigorous full-range moment-curvature analysis. An effective strategy is proposed for flexural ductility design of RC beams taking into account confinement. The key parameters considered include the maximum difference of tension and compression reinforcement ratios, and maximum neutral axis depth ratio at peak resisting moment. Empirical formulae and tables are then developed to provide guidelines accordingly.

• Journal of Power System Engineering
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• v.19 no.5
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• pp.25-31
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• 2015

This study deals with optimal conditions for design parameters of the multistage bollard with up and down installed on the street to protect pedestrians or stop cars. FE simulation and Taguchi method are used to achieve the optimization for the automatic multistage bollard to minimize effective stress caused by the external force. Thickness, height of stage 2, diameter and over-all height which affect its structural strength are chosen as design parameters. According to the experiments combined by orthogonal array, each of the effective stresses is evaluated. And the results are analyzed by using the signal to noise ratio concept of Taguchi method. From their results, the optimal combination of design parameters are proposed.

• Magazine of the Korean Society of Agricultural Engineers
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• v.27 no.4
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• pp.61-67
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• 1985

This study is concerned with the optimum design of reinforced concrete frame structure with multi-stories and multi-bays by Limit State Design Method aimed to establish a synthetical optimal method that can simultaneously acomplish structural analysis and sectional desig. For optimum solution, the Successive Linear Programming known as effective to nonlinear optimization problem: including both multi-design variables and mulit-constrained condition was applied. The developed algorithm was applied to an actual structure and reached following results. 1)The developed algorithm was rvey effective converging to an optimal solution with 3 to 5 iteration. 2)An optimal solution was showed when bending moment redistribution factor a was 0.80. 3)The column was, regardless of story, controlled by the long column when unbraced, while in case of braced column, it is designed with 3 short column controlled by thrust and bending moment, and the supporting condition had little effect on the optimization results.

• Journal of The Korean Digital Architecture Interior Association
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• v.12 no.4
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• pp.125-132
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• 2012

In this study based on BIM(Building Information Modeling) apply for performing efficient remodeling project and utilized. And this study will examine a real project where a BIM based process was used in the remodeling of an single-family homes. In the remodeling design phase of the planning process was conducted for the BIM process modeling, BIM in the remodeling stage while performing the required range and level of the remodeling process were studied. Based on this, communication between client and remodeling designer, participants more expect that smooth and speeds up in remodeling. For client decision support, troubleshooting of remodeling of the design process to be effective in the BIM have been identified. The BIM model and deliverables data used for the remodeling design process of building remodeling is the most effective way, due to the increased efficiency gained in many areas.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2007.11a
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• pp.157-158
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• 2007

This is an interior design for a furniture & lighting design exhibition. The concept of design is to secure the smooth flow planning of an audience and effective direction of an exhibit Design content include 1) installation(passage of light) to guide an audience from entrance to right side of the exhibition space to prohibit the flow dispersion and keep smooth continual circulation flow plan 2)image-wall to introduce exhibition 3)installation to help the global understanding of exhibit 4)exhibition stand design considering proper height of audience's eye.

• International Journal of Concrete Structures and Materials
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• v.8 no.2
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• pp.99-116
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• 2014

The American Concrete Institute (ACI) 318-11 permits the use of the moment magnifier method for computing the design ultimate strength of slender reinforced concrete columns that are part of braced frames. This computed strength is influenced by the column effective length factor K, the equivalent uniform bending moment diagram factor $C_m$ and the effective flexural stiffness EI among other factors. For this study, 2,960 simple braced frames subjected to short-term loads were simulated to investigate the effect of using different methods of calculating the effective length factor K when computing the strength of columns in these frames. The theoretically computed column ultimate strengths were compared to the ultimate strengths of the same columns computed from the ACI moment magnifier method using different combinations of equations for K and EI. This study shows that for computing the column ultimate strength, the current practice of using the Jackson-Moreland Alignment Chart is the most accurate method for determining the effective length factor. The study also shows that for computing the column ultimate strength, the accuracy of the moment magnifier method can be further improved by replacing the current ACI equation for EI with a nonlinear equation for EI that includes variables affecting the column stiffness and proposed in an earlier investigation.