• International Journal of Fuzzy Logic and Intelligent Systems
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• v.14 no.1
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• pp.8-16
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• 2014

We consider the visual barcode recognition problem in a noisy video data setup. Unlike most existing single-frame recognizers that require considerable user effort to acquire clean, motionless and blur-free barcode signals, we eliminate such extra human efforts by proposing a robust video-based barcode recognition algorithm. We deal with a sequence of noisy blurred barcode image frames by posing it as an online filtering problem. In the proposed dynamic recognition model, at each frame we infer the blur level of the frame as well as the digit class label. In contrast to a frame-by-frame based approach with heuristic majority voting scheme, the class labels and frame-wise noise levels are propagated along the frame sequences in our model, and hence we exploit all cues from noisy frames that are potentially useful for predicting the barcode label in a probabilistically reasonable sense. We also suggest a visual barcode tracking approach that efficiently localizes barcode areas in video frames. The effectiveness of the proposed approaches is demonstrated empirically on both synthetic and real data setup.

• Steel and Composite Structures
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• v.50 no.3
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• pp.337-345
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• 2024

This research proposed a particle swarm optimization (PSO) based seismic retrofit design of moment frame structures using a steel frame assembly. Two full scale specimens of the steel frame assembly with different corner details were attached to one-story RC frames for seismic retrofit, and the lateral load resisting capacities of the retrofitted frames subjected to cyclic loads were compared with those of a bare RC frame. The open source software framework Opensees was used to develop an analytical model for validating the experimental results. The developed analytical model and the optimization scheme were applied to a case study structure for economic seismic retrofit design, and its seismic performance was assessed before and after the retrofit. The results show that the developed steel frame assembly was effective in increasing seismic load resisting capability of the structure, and the PSO algorithm could be applied as convenient optimization tool for seismic retrofit design of structures.

• Proceedings of the IEEK Conference
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• 2003.11a
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• pp.153-156
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• 2003

This paper proposes a video tracking method for a deformable moving object using an active contour model. In order to decide the convergent directions of the contour points automatically, a new energy function based on a frame difference map and an updating rules of the frame difference map are presented. Experimental results on a set of synthetic and real image sequences showed that the proposed method can fully track a speedy deformable object while extracting the boundary of the object exactly in every frame.

• Transactions of the Korean Society of Automotive Engineers
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• v.19 no.4
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• pp.47-53
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• 2011

Firstly, FEM model for the body frame of a fuel cell vehicle was built up and design optimization results based on different schemes were exhibited. One scheme was to minimize weight while maintaining the normal mode frequencies and the other was to increase the frequencies without weight change. Next, for a rear frame model, shape parameter study on collapse characteristics such as peak resistance load and absorbed energy was carried out. Also, the stiffness of frame mounting brackets was predicted using inertance calculation and the durability of those mounting brackets for vehicle system loads was evaluated. Finally, for a representative mounting model, the influence on durability due to thickness change was analyzed.

• Structural Monitoring and Maintenance
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• v.5 no.2
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• pp.189-204
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• 2018

This paper examines the seismic responses of a reinforced concrete (RC) frame core-tube building with pre-pressed spring self-centering energy dissipation (PS-SCED) braces. The PS-SCED brace system consists of friction devices for energy dissipation, pre-pressed combination disc springs for self-centering and tube members as guiding elements. A constitutive model of self-centering flag-shaped hysteresis for PS-SCED brace is developed to better simulate the seismic responses of the RC frame core-tube building with PS-SCED braces, which is also verified by the tests of two braces under low cyclic reversed loading. Results indicate that the self-centering and energy dissipation capabilities are well predicted by the proposed constitutive model of the PS-SCED brace. The structure with PS-SCED braces presents similar peak story drift ratio, smaller peak acceleration, smaller base shear force and much smaller residual deformations as compared to the RC frame core-tube building with bucking-restrained braces (BRBs).

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2004.10a
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• pp.503-510
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• 2004

One of the methods improving the seismic behavior of a structure is the frame with reduced beam section (RBS) which cuts a segment of flanges of the beam near the beam-to-column connection so that the section with reduced flanges has smaller flexural strength than the beam end. It is difficult to analyze the RBS frame because RBS portion has circular-cut type flange. And inelastic response of the steel frame with the RBS is very sensitive to the RBS model. In this paper, the analytical models of RBS portion are investigated and the results of the inelastic analysis for RBS analytical models are compared and then the analytical model for RBS is determined based on the results of inelastic analysis. Inelastic behavior of the RBS frame and its dynamic characteristics are investigated for selected analytical model of RBS.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.1490-1495
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• 2005

In this study, Model test of concrete frame structures with various shapes and locations are carried out by means of applying Peck's(1969) settlement method. The results of the model test indicated that important correlations existed between the behavior of frame structure and ground movement. Also, the damage level of frame structure closely influenced by the phase of excavation. Therefore, prediction of damage level at early phase of construction should be very precise. The damage level graph by Cording et al.(2001), the angular distortion provided gradually more serious damage to frame structures for the all cases. But the damage level graph by Burland(1997), was difficult to confirm because of very small amount of deflection ratio.

• Journal of Korean Association for Spatial Structures
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• v.6 no.1 s.19
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• pp.45-54
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• 2006

A steel frame is one of the most commonly used structural systems due to its resistance to various types of applied loads. Many studies have been conducted to investigate the effects of connection flexibility, support conditions, and beam-to-column stiffness ratio on the story drift of a frame. Based on the results of these studies, several design guides have been proposed. This research has been conducted to predict the actual behavior of a double angle connection, and to establish its effect on the story drift and the maximum allowable load of a steel frame. For these purposes, several experimental tests were conducted and a simplified analytical model was proposed. This simplified analytical model consists of four spring elements as well as a column member. In addition, a point bracing system was proposed to control the excessive story drift of an unbraced steel frame.

• Structural Engineering and Mechanics
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• v.77 no.3
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• pp.383-394
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• 2021

Column foot in traditional Chinese timber structures may be subjected to be uplifted due to the lateral load and subsequently reset under the vertical loads. The residual moment of the rocking column foot is the most important parameter representing the mechanical behaviors of column foot, and the simplification of joints is the basis of structural analysis of whole structure. The complicated mechanical behaviors of joint and the modeling of the column foot joint has been undertaken historically based on the experiments and numerical simulation. On the condition of limited application range of those models, a lack of simplified model to represent the mechanical behaviors of joint deserves attentions. There is a great need to undertake theoretical studies to derive the residual moment and make better simplified model of the joint. This paper proposes the residual moment and equivalent simplified model of the rotational stiffness for column foot joint. And, the timber frame is established based on the simplified model, which is verified by solid finite element model. Results show that a mutual agreement on the mechanical behaviors of the timber frame is obtained between the simplified model and the solid finite element model. This study can serve as the references of the structural analysis for the traditional timber structures.

• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.5
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• pp.100-105
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• 2008

In the design process of an automobile part, several analysis methods are usually utilized to evaluate the performance of the part. However, most automobile design engineers do not directly utilize CAE (Computer Aided Engineering) tools since specific skills are required to obtain practical results. Moreover, CAE requires a huge amount of computation time and cost. In order to resolve these problems, a new design approach named First Order Analysis (FOA) technique has been proposed. In this paper, the FOA technique is employed to design a vehicle sub-frame. An equivalent model of the vehicle sub-frame which only consists of beam elements is proposed and the modal properties obtained with the model are compared to those obtained with a full scale finite element model. The effect of some parameter tolerances on the modal characteristics of the vehicle sub-frame is investigated by employing the FOA equivalent model.