• The Transactions of the Korean Institute of Electrical Engineers D
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• v.54 no.3
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• pp.166-173
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• 2005

Preserving image features, edges and details in the process of impulsive noise filtering is an important problem. To avoid image blurring, only corrupted pixels must be filtered. In this paper, we propose an effective impulse noise detection method using Self-Organizing Neural Network(SONN) which applies median filter selectively for removing random-valued impulse noises while preserving image features, edges and details. Using a $3\times3$ window, we obtain useful local features with which impulse noise patterns are classified. SONN is trained with sample image patterns and each pixel pattern is classified by its local information in the image. The results of the experiments with various images which are the noise range of $5-15\%$ show that our method performs better than other methods which use multiple threshold values for impulse noise detection.

• Journal of Information Science Theory and Practice
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• v.10 no.1
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• pp.45-58
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• 2022

Community enterprise plays an important role for developing local business. Products from local communities apply local specialties such as high-quality materials and inherited wisdom. This work aims to support merchandises from local community enterprises by bringing out their specialties related to local wisdom and intangible cultural aspects. An ontology is applied to demonstrate the innate information regarding the implicit values of the products and is used as a core for a semantic search system. Details of the products are gathered from their respective community using an interview method and are extracted to align with the developed ontological schema. The semantic search system thus is implemented with a recommendation process for online accessibility for providing the organised information. From evaluation, the developed ontology and its instances are rated highly for their consistency, conciseness, and completeness. In usage, accuracy of the query and recommendation results are evaluated at 97.38% searching accuracy and 85.03% for recommending interesting products.

• Structural Engineering and Mechanics
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• v.59 no.5
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• pp.867-883
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• 2016

In this paper, the effects of steel-fiber and rebar reinforcements on the ultimate bearing strength of the local anchorage zone were investigated based on experiments and comparisons between test results and design-equation predictions (AASHTO 2012, NCHRP 1994). Eighteen specimens were fabricated using the same anchorage device, which is one of the conventional anchorage devices, and two transverse ribs were used to secure an additional bearing area for a compact anchorage-zone design. Eight of the specimens were reinforced with only steel fiber and are of two concrete strengths, while six were reinforced with only rebars for two concrete strengths. The other four specimens were reinforced with both rebars and steel fiber for one concrete strength. The test and the comparisons between the design-equation predictions and the test results showed that the ultimate bearing strength and the section efficiency are highly affected by the reinforcement details and the concrete strength; moreover, the NCHRP equation can be conservatively applied to various local anchorage zones for the prediction of the ultimate bearing strength, whereby conditions such as the consideration of the rib area and the calibration factor are changed.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.04b
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• pp.525-530
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• 1998

The objective of this experiment is to observe the elastic and inelastic behaviors of high-rise reinforced concrete frames with nonseimic details. To do this, a building frame designed according to Korean seismic code and detailed in the Korean conventional manner was selected. An 1:12 scale plane frame model was manufactured according law. Reversed lateral load tests and monotonic push-over test were performed under the displacement control. To simulate the earthquake effect, the lateral force distribution was maintained to be an inversed triangular by using whiffle tree. From the tests, story displacements, lateral story forces, local plastic rotations and the relations between inter-story drift versus story shear are obtained. Based on the test results, conclusions on the characteristics of the elastic and behaviors of a high-rise reinforced concrete frame with nonseismic details are drawn.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.65-70
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• 2001

The compression toe of structural wall is designed to resist the axial compression and shear force caused by wind or earthquake. The performance of shear wall used in tall building is highly influenced by combined shear and axial force. For this reason, it is possible to result in local brittle failure because of concentrated damage in the potential plastic hinge region under severe earthquake. Thus, it is necessary to establish the lateral confinement details at the plastic hinge of shear wall so that shear wall can behave a ductile manner, The objective of this study is to evaluate the seismic performance of L-shaped walls with different confinement details. For this purpose, three wall specimens were tested experimentally and also analyzed using Nonlinear FEM package.

• Journal of Ocean Engineering and Technology
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• v.18 no.1
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• pp.22-27
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• 2004

An orthotropic steel deck system is widely adapted form for a long-span bridge. It has many advantages, such as the big reduction of dead weight, the simplicity for erection, and the reduction of the construction period. However, an orthotropic steel deck system requires a lot of welding work, which may result in defects and deformation of connection. Therefore, the research for the general behavior and fatigue strength of the several details in orthotropic steel deck bridge is necessary. The fatigue failure with distortion results from secondary stress by out-of-plane deformation; these kinds of cracks are very difficult to measure, and can not be precisely calculated through finite element analysis. This stress concentration phenomenon generates the fatigue failure around the lower scallop of the transverse rib. This paper presents improved details of the intersection between the longitudinal rib and the transverse rib of an orthotropic steel deck bridge by the third dimensional hit size test, and the finite element method, which can minimize local stress through parametric study.

• Mass Spectrometry Letters
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• v.11 no.4
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• pp.65-70
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• 2020

Despite its great success in the field of proteomics, mass spectrometry has limited use for determining structural details of peptides, proteins, and their assemblies. Emerging ion mobility spectrometry-mass spectrometry has enabled us to explore the conformational space of protein ions in the gas phase, and further combinations with the gas-phase ion spectroscopy and the collision-induced unfolding have extended its abilities to elucidating the secondary structure and local details of conformational transitions. This review will provide a brief introduction to the combined approaches of IMS-MS with gas-phase ion infrared spectroscopy or collision-induced unfolding and their most recent results that successfully revealed higher-order structural details.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.7
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• pp.977-985
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• 2004

An evaluation of fatigue life of welded components is complicated due to various geometrically complex welding details and stress raisers in vicinity of weld beads, ego under cuts, overlaps and blow holes. These factors have a considerable influence on the fatigue strength of welded joints, as well as the welding residual stress which is relaxed depending on the distribution of local stress at the front of the stress raisers. To reasonably evaluate fatigue life, the effect of geometries and welding residual stress should be taken into account. The several methods based on the notch strain approach have been proposed in order to accomplish this. These methods, however, result in differences between analytical and experimental results due to discrepancies in estimated amount of relaxed welding residual stress present. In this paper, an approach that involves the use of a modified notch strain approach considering geometrical effects and a residual stress relaxation model based on experimental results was proposed. The fatigue life for five types of representative welding details, ego cruciform, cover plate, longitudinal stiffener, gusset and side attachment joint, are evaluated using this method.

• IEMEK Journal of Embedded Systems and Applications
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• v.16 no.5
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• pp.225-232
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• 2021

Deraining is one of the image restoration tasks and should consider a tradeoff between local details and broad contextual information while recovering images. Current studies adopt an attention mechanism which has been actively researched in natural language processing to deal with both global and local features. This paper classifies existing deraining methods and provides comparative analysis and performance comparison by using several datasets in terms of generalization.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2002.10a
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• pp.354-361
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• 2002

This paper propose section properties factor to generate stress history for fatigue analysis and safety inspection of steel bridge. A methodology is described for the computation of numerical stress histories in the steel truss bridge, caused by the vehicles using section properties factor. The global 3-D beam model of bridge is combined with the local shell model of selected details. Joint geometry is introduced by the local shell model. The global beam model takes the effects of joint rigidity and interaction of structural elements into account. Connection nodes in the global beam model correspond to the end cross-section centroids of the local shell model. Their displacements are interpreted as imposed deformations on the local shell model. The load cases fur the global model simulate the vertical unit force along the stringers. The load cases fer the local model are imposed unit deformations. Combining these, and applying vehicle loads, numerical stress histories are obtained. The method is illustrated by test load results of an existing bridge.