• International Journal of Concrete Structures and Materials
• /
• v.11 no.2
• /
• pp.285-300
• /
• 2017

This study investigates the seismic performance of a staggered wall structure designed with conventional strength based design, and compares it with the performance of the structure designed by capacity design procedure which ensures strong column-weak beam concept. Then the seismic reinforcement schemes such as addition of interior columns or insertion of rotational friction dampers at the ends of connecting beams are validated by comparing their seismic performances with those of the standard model structure. Fragility analysis shows that the probability to reach the dynamic instability is highest in the strength designed structure and is lowest in the structure with friction dampers. It is also observed that, at least for the specific model structures considered in this study, R factor of 5.0 can be used in the seismic design of staggered wall structures with proposed retrofit schemes, while R factor of 3.0 may be reasonable for standard staggered wall structures.

• Structural Engineering and Mechanics
• /
• v.29 no.4
• /
• pp.381-390
• /
• 2008

This paper proposed a conceptual design of bascule bridge, which is a new kind of movable bridge with an aim of reducing the weight of superstructure. Compared with the traditional bascule bridge, the light bascule bridge chooses cable-stayed bridge with inclined pylon as its superstructure; therefore, the functions of balance-weight and structure will fuse into one. Otherwise, it adopts moving counterweight to adjust its center of gravity (CG) to open or close the bridge. In order to lighten the superstructure, it uses contact springs to auxiliary retract, and intelligent prestressing system (IPS) to control the main girder's deformation. Simultaneously the vibration control scheme of structure is discussed. Starting from establishing the mechanical model of bridge, this article tries to analyze the conditions that the design parameters of structure and attachments should satisfy to. After the design procedure was presented, an example was also adopted to explain the primary design process of this kind bridge.

• Proceedings of the Korea Society of Design Studies Conference
• /
• 2005.05a
• /
• pp.40-41
• /
• 2005

• Journal of the Society of Naval Architects of Korea
• /
• v.56 no.3
• /
• pp.187-199
• /
• 2019

In the case of gas carriers and oil tankers, pipes are installed on the upper deck as a moving passage to load LPG, LNG, crude oil, etc. Pipes used for loading or unloading liquid cargo in cargo holds are connected to the hull through support structures. However, many cases of hull damage have been reported where the various equipment and support structures are installed on the upper deck. It is assumed that not only the structural discontinuity where the hull and the pipe support structure meet, but also action due to the pipe loads and the hull girder bending moment are simultaneously affected. This paper deals with the design and strength evaluation of the support structure of pipes and cables installed on the upper deck of commercial ships and offshore structures. For these supporting structures, design conditions and working loads were defined. The design procedure was established through the structure analysis on the method of determining the member dimensions. A series of finite element analysis was performed on the factors to be considered in the design and the effects were discussed. The accuracy and design periods of the strength evaluation was improved and reduced by application of the automation program in the finite element analysis. It is also expected that the design reliability of the shipyard is improved.

• Korean Journal of Computational Design and Engineering
• /
• v.14 no.1
• /
• pp.33-41
• /
• 2009

Triangular mesh models are widely used in reverse engineering, computer graphics, rapid prototyping and NC(numerical controller) tool-path generation. Triangular mesh models are generated from point clouds, surface models and solid models. A halfedge-based triangular mesh data structure is proposed and the development considerations are presented. In the presented data structure, halfedge is the key data structure. Halfedge stores its triangle index and the order in the triangle. Triangles do not store the halfedge lists explicitly. Halfedge is referred by value and defined when it is required. Proposed data structure supports four design requirements: efficient rendering, compact memory, supporting efficient algorithms and easy programming.

• Steel and Composite Structures
• /
• v.26 no.2
• /
• pp.163-170
• /
• 2018

The purpose of this paper is to present a new and efficient optimization algorithm called Jaya for optimum design of steel grillage structure. Constrained size optimization of this type of structure based on the LRFD-AISC is carried out with integer design variables by using cross-sectional area of W-shapes. The objective function of the problem is to find minimum weight of the grillage structure. The maximum stress ratio and the maximum displacement in the inner point of steel grillage structure are taken as the constraint for this optimization problem. To calculate the moment and shear force of the each member and calculate the joint displacement, the finite elements analysis is used. The developed computer program for the analysis and design of grillage structure and the optimization algorithm for Jaya are coded in MATLAB. The results obtained from this study are compared with the previous works for grillage structure. The results show that the Jaya algorithm presented in this study can be effectively used in the optimal design of grillage structures.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.44 no.5
• /
• pp.950-968
• /
• 2020

This study derives the modern characteristics of the paisley ornament through an analysis of the paisley ornament shown in fashion since the 2010s based on a theoretical review of the paisley ornament used in Kashmir India shawls for artistic inspiration in the fashion-textile field. It classified the paisley ornament in fashion since the 2010s into types of 'basic structure of body and coif', 'abnormal paisley ornament shapes', 'complex structure of paisley ornament', 'complex structure with other motif', 'a pair of symmetrical reflection motif', 'regular of repetitive arrangement', 'complex arrangement of irregularity and regularity' and 'free arrangement of irregularity'. A comparative analysis with the historical paisley ornament shows that paisley ornaments have contemporary characteristics like 'Bisector structure of centerline in criterion of the body', 'Composite structure of extended 1-repeat', and 'Free structure of engineered placement'. A modern design was inspired by the historical art forms; however, it was used in free utilization of motifs and patterns in terms of size, direction, proportion and space. These were the expression of a design identity that originated from the aesthetic ability and career of a designer as well as the technology of computer programs for the improvements in time and cost efficiency.

• Journal of KSNVE
• /
• v.8 no.2
• /
• pp.267-273
• /
• 1998

This study aims at performing sensitivity analysis of piezoelectric smart structure for minimizing radiated noise from the structure, The structure consists of a flat plate on which disk shaped piezoelectric actuator is mounted, and finite element modeling is used for the structure. The finite element modeling uses a combination of three dimensional piezoelectric, flat shell and transition elements so thus it can take into account the coupling effects of the piezoelectric device precisely and it can also reduce the degrees of freedom of the finite element model. Electric potential on the piezoelectric actuator is taken as a design variable and total radiated power of the structure is chosen as an objective function. The objective function can be represented as Rayleigh's integral equation and is a function of normal displacements of the structure. For the convenience of computation, all degrees of freedom of the finite element equation is condensed out except the normal displacements of the structure. To perform the design sensitivity analysis, the derivative of the objective function with respect to the normal displacements is found, and the derivative of the norma displacements with respect to the design variable is calculated from the finite element equation by using so called the adjoint variable method. The analysis results are compared with those of the finite difference method, and shows a good agreement. This sensitivity analysis is faster and more accurate than the finite difference method. Once the sensitivity analysis program is used for gradient-based optimizations, one could achieve a better convergence rate than non-derivative methods for optimal design of piezoelectric smart structures.

• Geomechanics and Engineering
• /
• v.16 no.3
• /
• pp.321-329
• /
• 2018

Classic braced walls use struts and wales to minimize ground movements induced by deep excavation. However, the installation of struts and wales is a time-consuming process and confines the work space. To secure a work space around the retaining structure, an anchoring system works in conjunction with a braced wall. However, anchoring cannot perform well when the shear strength of soil is low. In such a case, innovative retaining systems are required in excavation. This study proposes an innovative earth-retaining wall that uses in situ soil confined in dual sheet piles as a structural component. A numerical study was conducted to evaluate the stability of the proposed structure in cohesionless dry soil and establish a design chart. The displacement and factor of safety of the structural member were monitored and evaluated. According to the results, an increase in the clearance distance increases the depth of safe excavation. For a conservative design to secure the stability of the earth-retaining structure in cohesionless dry soil, the clearance distance should exceed 2 m, and the embedded depth should exceed 40% of the wall height. The results suggest that the proposed method can be used for 14 m of excavation without any internal support structure. The design chart can be used for the preliminary design of an earth-retaining structure using in situ soil with dual steel sheet piles in cohesionless dry soil.

• KSCI Review
• /
• v.1 no.2
• /
• pp.73-94
• /
• 1995

In this paper, design of efficient NDB(Network Data Base) for the activation plan of chain information network. The DB structure build up, logical structure, store structure, physical structure, the data express for one's record, and the express using linked in the releation of data. Also express as hierarchical model on the DSD(Data Structure Diagram) from the database with logical structure. Each node has express on record type, the linked in course of connective this type, the infuence have efficent of access or search of data, in the design for connection mutually a device of physical, design for database, and construction a form of store for logical. Also activation of chain information network of efficent, using POS(Point Of Sale) system in OSI(Open Systems Interconnection) environment for network standardization, and build up network a design for system.