• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2002.05a
• /
• pp.684-687
• /
• 2002

In optical disk drive(ODD), pickup actuator, which comprises a key part of an optical disk drive equipment. must be thin. compact, and high sensitive. Low tilt is also an important requirement for the actuator, since optical disks are to high density. This tilt occurs from around the axis parallel to the tangential and radial direction of the disk. The main reason of the moment is the coupling effect between focus driving system and tracking driving system. This paper analyzed tut quantity due to focusing and tracking force through coupled fields analysts with electromagnetic analysis and structural analysis.

• Journal of the Korea Society for Simulation
• /
• v.23 no.2
• /
• pp.7-15
• /
• 2014

System operational performance analysis for wire-guided torpedo is intended to provide technical analysis data for requirements analysis and development, which, as a consequence, supports the requirements definition activity for systems engineering. Technical approach and analysis example are presented including problem definition, formulation, modeling, simulation and analysis results that are applied to the on-going Next Generation Torpedo project.

• Journal of Aerospace System Engineering
• /
• v.15 no.6
• /
• pp.10-18
• /
• 2021

A flame deflector prevents a launch system from thermal damage by deflecting the exhaust flame of the launch vehicle. During the deflection of the flame, the flame deflector is subjected to a high-temperature and high-pressure flow, which results in thermal ablation damage at the surface. Predicting this ablation damage is an essential requirement to ensure a reliable design. This paper introduces a numerical method for predicting the ablation damage phenomena based on a one-way fluid-structure interaction (FSI) analysis. In the proposed procedure, the temperature and convective heat transfer coefficient of the exhaust flame are calculated using a fluid dynamics analysis, and then the ablation is calculated using a finite element analysis (FEA) based on the user-subroutine UMESHMOTION and Arbitrary Lagrangian-Eulerian (ALE) adaptive mesh technique in ABAQUS. The result of such an analysis was verified by comparison to the ablation test result for a flame deflector.

• IEMEK Journal of Embedded Systems and Applications
• /
• v.13 no.6
• /
• pp.305-312
• /
• 2018

Software has been used to develop many functions of the modern weapon systems which has a high mission criticality. Weapon system software must consider multi-threaded processing to satisfy growing performance requirement. However, developing multi-threaded programs are difficult because of concurrency faults, such as unintended data races. Especially, it is important to prepare analysis for debugging the data races, because the weapon system software may cause personal injury. In this paper, we present an efficient framework of analysis, called ConDeWS, which is designed to determine the scope of dynamic analysis through using the result of static analysis and fault analysis. As a result of applying the implemented framework to the target software, we have detected unintended data races that were not detected in the static analysis.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2023.05a
• /
• pp.333-334
• /
• 2023

Interest in the commercialization of research results is increasing according to the recent social atmosphere. In the field of construction, new technologies are also being actively commercialized. Pre-analysis of products is an important procedure for future market entry. This study aims to conduct a product-based importance-performance analysis as one of the preliminary analysis methods for the commercialization of technologies developed in the field of construction and to explore their applicability. This study conducts a survey on those involved by setting the categories of product quality, convenience, and usability for the commercialization of previously developed pipeline inspection product. Based on this, we would like to present an analysis that calculates importance and performance of the product and helps to set the development direction through interrelationship analysis.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2002.05a
• /
• pp.437-442
• /
• 2002

The purpose of this study is to investigate nonlinear behavior and estimate ultimate resistance of the wall structure against seismic loading. Experimental data for RC coupling elements are used for specifying the strength deterioration and stiffness degradation factor of hysteretic model. Modified coupling element models are used in the push over analysis and time history analysis. In the time history analysis, three earthquake waves are used in the analysis and their peak ground accelerations are changed to be 0.2g. The conclusions of this study are as follows : (1) In the push over analysis, yielding of coupling elements occurred at lower story with small story drift ratio as 0.3%. (2) In the time history analysis, the story drift ratio is sufficient for the requirement of Korean Code, But coupling elements at most stories of the buildings occurred yielding. i. e. the earthquake resistant capacity of shear wall structures is not sufficient at 0.2g.

• Proceedings of the Korean Society For Composite Materials Conference
• /
• 2002.10a
• /
• pp.5-9
• /
• 2002

This paper presents a method and procedure for stress analysis and sizing in development of structures of a large composite wind turbine blade. Structural requirement of IEC standard was reviewed to set up appropriate analysis method and procedure. Several structural layouts were examined in a viewpoint of a large scale wind turbine blade. For the critical load cases, stress analysis were performed using finite element method. Stacking sequence and thickness of a laminate for each part and location were determined considering stress levels and producibility. Nonlinear geometric analysis was performed to check stability problem due to local buckling of a skin structures.

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 2006.04a
• /
• pp.467-472
• /
• 2006

The purpose of this paper is to check the structural safety of the network equipments by performing the static and dynamic finite element analysis. The stress and displacement of structures under static loading condition are evaluated to check whether satisfying the design requirement conditions. Since the computed natural frequencies are similar to the results of experiment. the model could be used for the response spectrum analysis where experimental acceleration value at each frequency are used as seismic input excitation. It is shown that the analysis results are a little bit larger than that of the experimental values. Also sensitivity analysis and optimization for the natural frequency are performed and it is found that the first natural frequency is very sensitive to the stiffness of the equipment.

• International Journal of Aerospace System Engineering
• /
• v.4 no.2
• /
• pp.1-4
• /
• 2017

This work dealt with design and manufacturing of WIG vehicle wing using carbon/epoxy composite materials. In this study, structural design and analysis of carbon composite structure for WIG craft were performed. Firstly, structural design requirement of wing for WIG vehicle was investigated. After structural design, the structural analysis of the wing was performed by the finite element analysis method. It was performed that the stress, displacement and buckling analysis at the applied load condition. And also, manufacturing of subscale wing using carbon/epoxy composite materials was carried out. After structural test of target structure, structural test results were compared with analysis results. Through the structural analysis and test, it was confirmed that the designed wing structure is safety.

• Proceedings of the KIEE Conference
• /
• 2005.10c
• /
• pp.299-301
• /
• 2005

The urban transit system is operated by driverless and automatic.In driverless and automatic system, the system function is accomplished exactly to obtain the safety and reliability of system and the system is designed to minimize risk. In order to design the system, the functional analysis is performed. Recently functional analysis is performed by design toolwhich is used and verified by aerospace, military, etc. Generally, the design tool is used to perform functional analysis in urban transit system development project. The design toolassist the system engineer to analysis the function of system in basic design. Therefore, In this paper, it is performed the functional analysis to satisfy the system requirement of urban transit system and to confirm the operation of system using design tool.