• Journal of the Korea Institute of Military Science and Technology
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• v.16 no.4
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• pp.430-434
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• 2013

In this paper, we have investigated deformation of cup for EFI detonator in high velocity impact test. The experimental result shows that STS cup deformed 0.170 mm with the bulged shape. The numerical simulation result with static/dynamic material properties of SUS304 shows 0.166 mm of deformation. The main parameters to decrease the deformation of cup are stength, thickness and density of cup. The initial condition of SUS304 cup was strength of 215 MPa and thickness of 0.12 mm. As strength increases to 500 MPa, deformation of cup converges to 0 mm, and as thickness increases to 0.18 mm, deformation of cup converges to 0 mm. If the density of cup decreases from 8 to 2.7 g/cc, the deformation of cup decreases to 0.141 mm.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.3
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• pp.140-148
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• 2003

An analysis fur the warping process has been performed to design the warper beam. Nonlinear material response is included in the physical model of polyester yarn. Large deformation finite element simulation considering contact and frictional analysis are used to obtain the pressure on the barrel of the warper beam. Loading condition on the flange is assumed by using the pressure on the barrel, winding number of yarn, Poisson's ratio of fiber, and fiber volume fraction. By using the above loading conditions NASTRAN finite element simulation is performed to calculate stress distribution and deformation of the warper beam. By comparing the deformed shape of the flange with experimental result, loading condition on the flange has been obtained. The obtained loading conditions on the barrel and flange can be utilized to design the warper beam.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.16 no.8 s.113
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• pp.886-892
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• 2006

Hot spot phenomenon is caused by non-uniform contact area between brake pad and disk frequent braking. Brake disk deformed by locally concentrated heat increases magnitude of frictional vibration. And this deformation can highly influence the judder vibration. In this experimental study, vibration and hot spot was measured in accordance with rotation of disk and pressure of master cylinder for finding the factors that causes hot spot phenomena. For comparing hot spot aspects with mode shapes of disk, mode shapes were measured by conducting modal test, and analyzed by using finite element analysis. Relation between hot spot phenomenon, and mode shape, pressure of master cylinder and rotation speed of disk respectively, was achieved by hot spot measurement and frequency analysis.

• Journal of Korea Multimedia Society
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• v.18 no.1
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• pp.1-8
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• 2015

In recent years, ear has emerged as a new biometric trait, because it has advantage of higher user acceptance than fingerprint and can be captured at remote distance in an indoor or outdoor environment. This paper proposes an individual identification method using ear region based on SIFT(shift invariant feature transform). Unlike most of the previous studies using rectangle shape for extracting a region of interest(ROI), this study sets an ROI as a flexible expanded region including ear. It also presents an effective extraction and matching method for SIFT keypoints. Experiments for evaluating the performance of the proposed method were performed on IITD public database. It showed correct identification rate of 98.89%, and it showed 98.44% with a deformed dataset of 20% occlusion. These results show that the proposed method is effective in ear recognition and robust to occlusion.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1999.10a
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• pp.305-312
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• 1999

A four-story reinforced concrete frame building model is designed for the gravity loads. only Static nonlinear pushover analyses are performed in two orthogonal horizontal directions. The overall capacity curves are converted into ADRS spectra and compared with demand spectra. At several points the deformed shape moment and shear distribution are calculated. It is observed that the seismic capacity may not meet the design requirements in soft soil condition and may collapse in MCE. It is concluded that limited but adequate amount of ductility need be provided in the seismic design in low to moderate seismicity regions.

• Korean Journal of Metals and Materials
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• v.47 no.11
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• pp.694-698
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• 2009

The $Co_{3}Ti$ phase hardens appreciably by the fine precipitation of disordered fcc Co-rich phase upon aging after quenching from solution annealing temperature. Transmission electron microscope (TEM) observations revealed that the precipitates are platelet in shape, lying nearly parallel to the {100} planes of the $Ll_{2}$-ordered matrix, and perfectly coherent with the matrix lattice at the beginning of aging. The high temperature strength increases appreciably with the fine precipitation of disordered Co-rich phase over the whole temperature range investigated. TEM observations of the under-aged and deformed alloys revealed that superdislocations are pinned by precipitates indicating an attractive interaction between dislocations and precipitates. In the over-aged state, thin twins are introduced in the fcc Co-rich precipitates during deformation.

• Journal of the Korean Society for Precision Engineering
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• v.13 no.11
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• pp.124-131
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• 1996

The dynamic material property of Mn-B ally high-strength steel is investigated through the rod impact test which is one of simple test methods for the analysis of the material behavior under high-strain-rate. Rod impact test is performed to produce the deformed shape of rod and analyzed by the one-dimensional theory based on conservation law and the two-dimensional hydrocode AUTODYN-2D. The dynamic yield stress is determined and compared with the static yield stress to investigate the strain-rate sensitivity of Mn-B alloy high-strength steel.

• Journal of the Korean Society of Clothing and Textiles
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• v.28 no.2
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• pp.270-279
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• 2004

The purpose of this study is to make a basic resource in developing a design satisfying male consumers＇ fashion inclination by examining the features of the men＇s fashion style shown in the fashion collections. Collected were 1,291 photos relating to the suit style through the analysis on the men＇s fashion collections for 8 years(1995-2002). Representative men＇s fashion images are extracted from these photos, then figurative features were analyzed and typified according to image, and finally representative fashion styles were presented and its meaning was analyzed. Representative men＇s fashion images are Sophisticated, Casual, Elegant, Active, Natural, Classic, Romantic, Ethnic, Military, Marine, Colonial, and Avant-garde. With the subcategories such as detailed shape of jacket and trousers, the relationship of color between upper and lower clothes, type and organizing method of material quality, type and arranging method of pattern, and coordination, the extracted fashion images were analyzed the figurative features. After finding out the common and different features, four men＇s fashion styles were suggested. Formal style maintains the typical suit style and has the feature expressing the men＇s authority, tradition, and honor. It includes Sophisticated, Elegant. and Classic image. Casual St Sporty style has the feature that there is a change in the volume of suit by adding activity to the typical suit style. It includes Casual, Active, and Natural image. Uniformed style is that political and social environment such as war has an influence on the suit design. It includes Military, Marine, and Colonial image. Deformed style has the feature that it suggests new type instead of adhering to the typical suit design. It includes Ethnic, Romantic, and Avant-garde image.

• Journal of the Optical Society of Korea
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• v.18 no.5
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• pp.523-530
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• 2014

Machine material and structural strain are critical factors for appraising mechanical properties and safety. Particularly in three and four-point bending tests, which appraise the deflection and flexural strain of an object due to external force, measurements are made by the crosshead movement or deflection meter of a universal testing machine. The Digital Image Correlation (DIC) method is one of the non-contact measurement methods. It uses the image analyzing method that compares the reference image with the deformed image for measuring the displacement and strain of the objects caused by external force. Accordingly, the advantage of this method is that the object's surface roughness, shape, and temperature have little influence. However, its disadvantage is that it requires extensive time to compare the reference image with the deformed image for measuring the displacement and strain. In this study, an algorithm is developed for DIC that can improve the speed of image analysis for measuring the deflection and strain of an object caused by a three-point bending load. To implement this algorithm for improving the speed of image analysis, LabVIEW 2010 was used. Furthermore, to evaluate the accuracy of the developed fast correlation algorithm, the deflection of an aluminum specimen under a three-point bending load was measured by using the universal test machine and DIC measurement system.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.25 no.3
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• pp.195-202
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• 2012

Two nonlinear frame elements taking into account geometric nonlinearity is presented and compared based on the Lagrangian co-rotational formulation. The first frame element is believed to be geometrically-exact because not only tangent stiffness matrices is exactly evaluated including stiffness matrices due to initial deformation but also total member forces are directly determined from total deformations in the deformed state. Particularly two exact tangent stiffness matrices based on total Lagrangian and updated Lagrangian formulation, respectively, are verified to be identical. In the second frame element, the deformed curved shape is regarded as the polygon and current flexural deformations in iteration process are neglected in evaluating tangent stiffness matrices and total member forces. Two numerical examples are given to demonstrate the accuracy and the good performance of the first frame element compared with the second element. Furthermore it is shown that the first frame element can be used in tracing nonlinear behaviors of cable members.