• Journal of Ocean Engineering and Technology
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• v.30 no.4
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• pp.277-286
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• 2016

The first part of this study found the tendencies of the mechanical properties of two arctic structural steels (EH32 and FH32). In the second part, the crashworthiness of stiffened panels scaled down from the side frame structure of a Korean research icebreaker was determined. A procedure for designing the shapes and sizes of the stiffened panels, mass and shape of a drop striker, and a large temperature chamber, and then manufacturing these, is introduced in detail. From impact bending tests for the stiffened panels, the residual permanent deformations and deformation histories over time were captured using manual measurement and video image analyses. Numerical simulations of the impact bending tests were carried out for three different finite element models, which were mainly composed of shell elements, solid elements, and solid elements, with welding beads. It was proven from a comparison of the test results and numerical simulation results that the solid element model with the welding bead consideration approached the test results in terms of the residual deformations as long as the strain rate effect was taken into account.

• Journal of Korean Society of Steel Construction
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• v.25 no.5
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• pp.519-530
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• 2013

Cyclic tests on modular building units for low-rise buildings composed of stud panels and a light-weight steel perimeter frame, were performed to evaluate the earthquake resistance such as stiffness, load-carrying capacity, ductility, and energy dissipation per load cycle. The strap-braced and sheeted stud panels were used as the primary lateral load-resistant element of the modular building units. Test results showed that the modular building units using the strap-braced and sheeted stud panels exhibited excellent post-yield ductile behaviors. The maximum drift ratios were greater than 5.37% and the displacement ductility ratios were greater than 5.76. However, the energy dissipation per load cycle was poor due to severe pinching during cyclic loading. Nominal strength, stiffness, and yield displacement of the modular building units were predicted based on plastic mechanisms. The predictions reasonably and conservatively correlated with the test results. However, the elastic stiffness of the strap-braced stud panel was significantly overestimated. For conservative design, the elastic stiffness of the strap-braced stud panel needs be decreased to 50% of the nominal value.

• The Research Journal of the Costume Culture
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• v.8 no.2
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• pp.261-271
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• 2000

In order to investigate the function and feature of western men's underclothes in the second half of the 19C, in this study, the historical changes of western men's underclothes are compared the first half of the 19C with the second half of the 19C. In the second half of the 19C, the useful function to ease for body was important. In the 1860's, for day-shirt, the tucked panels was disappeared and the front was pain. But the evening dress-shirt continued to show an expansive front tucked. Coloured shirts was used for country and sporting occasions. Ready-made underwear was used. In the 1870's, the plain breast was introduced and the Gladstone collar was used. Paper collars and dickeys were unfashionable. The drawers was composed a gusset at the back of the waistband. The dress of one generation was became the livery of the next. In the 1880's, a new feature was one stud and the use of pique for the breast. Coloured shirt was composed of stripes across the breast. In the 1890's, height of the collar steadily increased. The coat-shirt and regatta shirt became popular. The nice choice of shirt, collar and tie was a matter of supreme importance .The social status of the white shirt was further threatened by fancy coloured shirts. The mode of relaxation affected sports shirts. By the close of this period, both sexes accepted the hygienic rule of wool next the skin.

• Transactions of Materials Processing
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• v.8 no.1
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• pp.7-13
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• 1999

In this study, side panels were developed using the laser-welded tailored blank (T.B.) of both the same thickness and different thickness. At first, the formability of the same thickness T.B. was investigated to compare with one of the non-welded panel with respect to weldline movement and strain distribution in blank during the stamping process. Based on these results, we determined the weld line positions and the die step for T.B. forming of the blanks composed of different thickness combination. Then we made some stamping tryouts with selected types of blanks to investigate the formability of T.B. of the different thickness. During the tryouts, wrinkles were found in the a-pillar lower region which is under the deformation mode of the shrink flange. In the b-pillar region, fractures were also found. These defects have been reduced and corrected by controlling the blank design, the die faces and process parameters.

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.1
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• pp.125-132
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• 2002

Recently, ULSAB(Ultra Light Steel Auto Body) concept is getting more attention due to various benefits in automotive body design. One of the ULSAB efforts is making a door with TWB(Tailor Welded Blanks). In TWB, two or more patches of steel panels are welded together before stamping process. In this research, domains and thicknesses of the patches in a front door structure are determined by a series of optimization schemes composed of topology, size and shape optimization and DOE(Design of Experiments) scheme. A door is designed to have better performances compared to exiting structure considering static stiffness and natural frequency. The final design is discussed and compared to the existing design.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.15 no.8 s.101
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• pp.924-930
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• 2005

Sound absorptive materials have good performance in high frequency range, not at low frequencies. Therefore it has been great challenge to develop a sound absorbing structure that is good at low frequency. We propose to use a Helmholtz resonator array panel for this purpose. A Helmholtz resonator is one of noise control elements widely used in many practical applications. The resonator is a simple structure composed of a rigid-walled cavity with a neck, but it has very high performance at resonance frequency. This paper discusses the sound absorption of Helmholtz resonator array panels at normal and random incidence. First, various experimental results are introduced and studied. Secondly, we theoretically predict the absorptive characteristics of the resonator away panel. The theoretical approach is based on the Fourier analysis for a periodic absorber. We believe that this method can be used to design a panel for low frequency noise control.

• Journal of the Korea Computer Industry Society
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• v.2 no.4
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• pp.521-536
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• 2001

The objective of this study was to develop curriculum for successful articulation education program between department of information processing in Daejonsinil vocational high school and school of computer & communication in Hyechon College. This study was carried out through review of literature, survey and discussions with panels of judges composed of experts in the related fields. Gap analysis was used to interpret the survey results. Based on the results of this study, several educational needs and recommendations for articulation education of computer & communication area both in vocational high school and college were suggested.

• Journal of the Korean Society of Safety
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• v.21 no.3 s.75
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• pp.94-100
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• 2006

The goal of this study is to show the way to increase the safety of deteriorated PSC beam bridges by the to-box reinforcing method. This method is to change the open girder section into the closed box section by connecting bottom flanges of neighboring PSC girders with the precast panels embedding PS tendons at the anchor block. The box section is composed of three concrete members with different casting ages, RC slab, PSC beam, precast panel. This different aging requires a time-dependent analysis considering construction sequences. Reliability index and failure probability are produced by the AFOSM reliability analysis. Transversely five schemes and longitudinally two schemes are considered. The full reinforcing scheme, transversely and longitudinally, shows the highest reliability index, but it requires more cost for retrofit. The partial reinforcing scheme 4, 4-1 are recommended in this study as the economically best scheme.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.52 no.1
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• pp.35-41
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• 2003

In this paper, a machine vision system for recognizing and classifying the patterns and marks engraved by die molding or laser marking on the glass panels of computer monitors is suggested and evaluated experimentally. The vision system is equipped with a neural network and an NGC pattern classifier including searching process based on normalized grayscale correlation and adaptive binarization. This system is found to be applicable even to the cases in which the segmentation of the pattern area from the background using ordinary blob coloring technique is quite difficult. The inspection process is accomplished by the use of the NGC hypothesis and ANN verification. The proposed pattern recognition system is composed of three parts: NGC matching process and the preprocessing unit for acquiring the best quality of binary image data, a neural network-based recognition algorithm, and the learning algorithm for the neural network. Another contribution of this paper is the method of generating the training patterns from only a few typical product samples in place of real images of all types of good products.

• International Journal of Automotive Technology
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• v.5 no.3
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• pp.209-213
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• 2004

The objective of this paper is to introduce the noise reduction characteristics of a double gap system, which is composed of two air-gaps and two partition sheets. The resonance of acoustic modes of an enclosed cavity can be effectively suppressed by installing the double gap system in the cavity. It is revealed from a simple, one-dimensional model that the double gap system is more effective than the single gap system that consists of one air-gap and one partition sheet, in that the former requires a smaller space than the latter. Finally, these theoretical conclusions are verified by comparison experiments using an actually manufactured enclosed cavity, of which the boundary surfaces are made of thick panels that can be assumed as rigid walls.