• Journal of Korean Society of Steel Construction
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• v.17 no.6 s.79
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• pp.649-660
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• 2005

Since the diaphragm manhole of steel box girder bridges is designed generally from experience, it has become the primary factor in the excessive cost of steel bridge construction. For the economical and efficient manufacture of diaphragm manholes, it is necessary to study the exact behavior of the diaphragm manhole in a steel box girder bridge. In this study, both an experimental test and a structural analysis are performed to verify the behavior of the diaphragm manhole in a steel box girder bridge. A detailed structural analysis was performed according to various diaphragm manhole shapes, and in conclusion, the suitable reinforcement method for the support of diaphragm manholes in steel box bridges is presented.

• Proceedings of the KSR Conference
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• 2005.11a
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• pp.229-234
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• 2005

Thin-walled multicell box girders subjected to an eccentric load can he produced the three global behaviors of flexure, torsion, and distortion. Specially in railway bridges subjected to much eccentric load, it is quite important to evaluate influences of torsion and distortion. But it is very difficult to evaluate each influences of major behaviors numerically. If we can decompose an eccentric load P into flexural, torsional, and distortional forces. we can execute quantitative analysis each influences of major behaviors. Decomposition of Applied Load for Thin-walled Rectangular multi-cell box girders is reserched by Park, Nam- Hoi(Development of a multicell Box Beam Element Including Distortional Degrees of Freedom, 2003). But researches about trapezoidal multi-cell section is insufficient. So, this paper deals with multi-cell trapezoidal box girders. An expanded method, which is based on the force decomposition method for a single cell box girder given by Nakai and Yoo, is developed herein to decompose eccentric load Pinto flexural, torsional, and distortional forces. Derive formulas by decomposition of eccentric load is verified by 3D shell-modelling numerical analysis.

• Journal of Korea Multimedia Society
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• v.24 no.2
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• pp.305-311
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• 2021

One of the highly reliable object tracking methods is to trace objects by associating objects detected by deep learning. The detected object is represented by a rectangular box. The box has information such as location and size. Since the tracker has motion information of the object in addition to the location and size, knowing additional information about the motion of the detected box can increase the reliability of object tracking. In this paper, we present a new method of reliably estimating the moving direction of the detected object in underground parking lot. First, the frame difference image is binarized for detecting motion energy, change due to the object motion. Then, a cumulative binary image is generated that shows how the motion energy changes over time. Next, the moving direction of the detected box is estimated from the accumulated image. We use a new cost function to accurately estimate the direction of movement of the detected box. The proposed method proves its performance through comparative experiments of the existing methods.

• Proceedings of the IEEK Conference
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• 2003.11b
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• pp.255-258
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• 2003

This paper defines Normalized Term Frequency Weighting method for automatic text categorization by using Box-Cox, and then it applies automatic text categorization. Box-Cox transformation is statistical transformation method which makes normalized data. This paper applies that and suggests new term frequency weighting method. Because Normalized Term Frequency is different from every term compared by existing term frequency weighting method, it is general method more than fixed weighting method such as log or root. Normalized term frequency weighting method's reasonability has been proved though experiments, used 8000 newspapers divided in 4 groups, which resulted high categorization correctness in all cases.

• Proceedings of the Korean Vacuum Society Conference
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• 1997.07a
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• pp.74-74
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• 1997

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1996.10a
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• pp.322-329
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• 1996

The objective of this study is to develop the CAD system for 2 cell box culvert by ultimate strength design method. C-language & AutoCAD Rl2 were used to create user-friendly computing environment. Consequently, users can easily design 2 cell box culvert under the various conditions, such as design load, total fill depth, underground water level, strength of concrete, and so forth. This system is believed to improve the efficiency and economy by the batch processing of structural analysis, quick drafting and computation of material quantity in the 2 cell box culvert design.

• The Journal of the Acoustical Society of Korea
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• v.21 no.4
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• pp.415-420
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• 2002

To identify linear parameters of loudspeaker, two methods are presented. Linear parameter identification methods by box method and added mass method are developed. These methods are compared with conventional software to show advantages and disadvantages of developed methods. Results identified by conventional method of Laud software are significantly different from developed methods. But two methods developed show 4% error in Thiele-Small (TS) parameters identified. In box method, it shows that TS parameters are dependent on the amount of porous material.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.4
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• pp.1-6
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• 2020

This paper proposes the design of an advanced S-Box for calculating multiplicative inverse in AES encryption process. In this approach, advanced S-box module is first designed based on composite field, and then the performance evaluation is performed for S-box with multi-stage pipelining architecture. In the proposed S-Box architecture, each module for multiplicative inverse is constructed using combinational logic for realizing both small-area and high-speed. Through logic synthesis result, the designed 3-stage pipelined S-Box shows speed improvement of about 28% compared to the conventional method. The proposed advanced AES S-Box is performed modelling at the mixed level using Verilog-HDL, and logic synthesis is also performed on Spartan 3s1500l FPGA using Xilinx ISE 14.7 tool.

• Structural Engineering and Mechanics
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• v.69 no.2
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• pp.193-204
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• 2019

This paper presents results from experimental and numerical studies on the response of steel-concrete composite box bridge girders under certain localized fire exposure conditions. Two composite box bridge girders, a simply supported girder and a continuous girder respectively, were tested under simultaneous loading and fire exposure. The simply supported girder was exposed to fire over 40% of its span length in the middle zone, and the two-span continuous girder was exposed to fire over 38% of its length of the first span and full length of the second span. A measurement method based on comparative rate of deflection was provided to predict the failure time in the hogging moment zone of continuous composite box bridge girders under certain localized fire exposure condition. Parameters including transverse and longitudinal stiffeners and fire scenarios were introduced to investigate fire resistance of the composite box bridge girders. Test results show that failure of the simply supported girder is governed by the deflection limit state, whereas failure of the continuous girder occurs through bending buckling of the web and bottom slab in the hogging moment zone. Deflection based criterion may not be reliable in evaluating failure of continuous composite box bridge girder under certain fire exposure condition. The fire resistance (failure time) of the continuous girder is higher than that of the simply supported girder. Data from fire tests is successfully utilized to validate a finite element based numerical model for further investigating the response of composite box bridge girders exposed to localized fire. Results from numerical analysis show that fire resistance of composite box bridge girders can be highly influenced by the spacing of longitudinal stiffeners and fire severity. The continuous composite box bridge girder with closer longitudinal stiffeners has better fire resistance than the simply composite box bridge girder. It is concluded that the fire resistance of continuous composite box bridge girders can be significantly enhanced by preventing the hogging moment zone from exposure to fire. Longitudinal stiffeners with closer spacing can enhance fire resistance of composite box bridge girders. The increase of transverse stiffeners has no significant effect on fire resistance of composite box bridge girders.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.165-168
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• 2008

This paper presents the design, fabrication and performance of a reinforced concrete beam strengthened by GFRP box plate and its possibility for structural rehabilitations. The load capacity, ductility and failure mode of reinforced concrete structures strengthened by FRP box plate were investigated and compared with traditional FRP plate strengthening method. This is intended to assess the feasibility of using FRP box plate for repair and strengthening of damaged RC beams. A series of four-point bending tests were conducted on RC beams with or without strengthening FRP systems the influence of concrete cover thickness on the performance of overall stiffness of the structure. The parameters obtained by the experimental studies were the stiffness, strength, crack width and pattern, failure mode, respectively. The test yielded complete load-deflection curves from which the increase in load capacity and the failure mode was evaluated.