• Proceedings of the SAREK Conference
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• 2005.06a
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• pp.21-21
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• 2005

• Proceedings of KOSOMES biannual meeting
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• 2017.04a
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• pp.252-252
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• 2017

• Structural Engineering and Mechanics
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• v.86 no.6
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• pp.715-730
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• 2023

Broad studies have addressed the issue of structural element damage identification, however, rubber bearing, as a key component of load transmission between the superstructure and substructure, is essential to the operational safety of a bridge, which should be paid more attention to its health condition. However, regarding the limitations of the traditional bearing damage detection methods as well as few studies have been conducted on this topic, in this paper, inspired by the model updating-based structural damage identification, a two-stage bearing damage identification method has been proposed. In the first stage, we deduce a novel bearing damage localization indicator, called element relative MSE, to accurately determine the bearing damage location. In the second one, the prior knowledge of bearing damage localization is combined with sailfish optimization (SFO) to perform the bearing damage estimation. In order to validate the feasibility, a numerical example of a 5-span continuous beam is introduced, also the noise robustness has been investigated. Meanwhile, the effectiveness and engineering applicability are further verified based on an experimental simply supported beam and actual engineering of the I-40 Bridge. The obtained results are good, which indicate that the proposed method is not only suitable for simple structures but also can accurately locate the bearing damage site and identify its severity for complex structure. To summarize, the proposed method provides a good guideline for the issue of bridge bearing detection, which could be used to reduce the difficulty of the traditional bearing failure detection approach, further saving labor costs and economic expenses.

• Journal of Ocean Engineering and Technology
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• v.21 no.1 s.74
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• pp.40-44
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• 2007

This paper presents the experimental results on slamming phenomenon. The air pressure cylinder was used to ensure repeatability of the impact. The results showed that the adopted experimental technique was excellent in terms of repeatability, compared to that of the free drop tests. The pressure time histories, magnitude of peak pressure and the behavior of jetspray were obtained. The flat specimen was tested for various incident angles. To estimate the incident speed of the specimen, a high-speed camera was used. The high-speed camera was also a useful tool in understanding the behavior.

• Proceedings of the IEEK Conference
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• 2002.07c
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• pp.1823-1826
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• 2002

On modern computer culture, the high quality data is required in multimedia systems. So, the technology of data compression fur data transmission is necessary now. This paper presents the pipeline architecture for the low and column address generator of 2D DCT/IDCT (Discrete Cosine Transform/Inverse Discrete Cosine Transform. In the proposed architecture, the area of hardware is reduced by using the DA (distributed arithmetic) method and applies the concepts of pipeline to the parallel architecture. As a result the designed pipeline of the low and column address generator for 2D DCT/IDCT architecture is implemented with an efficiency and high speed compared with the non-pipeline architecture.

• ETRI Journal
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• v.35 no.4
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• pp.666-676
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• 2013

With the recent growth in smartphone services, the "mobile" environment has become a key factor to consider in the design of the future Internet. In this paper, we propose Mobile-Oriented Future Internet (MOFI), which is a new architecture for the future Internet for mobile-oriented environments. The MOFI architecture is designed with three functional features: global identifier and local locator in the identifier-locator separation, query-first data delivery for route optimization, and distributed control of identifier-locator mapping. The proposed architecture and functional operations are implemented and tested using the Linux platform. From the experiment results, we see that the MOFI architecture performs better than the existing identifier-locator separation schemes, such as Proxy Mobile IP and Host Identity Protocol, in terms of data throughout, mapping control overhead, and handover delay.

• JSTS:Journal of Semiconductor Technology and Science
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• v.11 no.1
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• pp.6-14
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• 2011

This paper presents a high-speed QR decomposition architecture for the multi-input-multi-output (MIMO) receiver based on Givens rotation. Under fast-varying channel, since the inverse matrix calculation has to be performed frequently in MIMO receiver, a high performance and low latency QR decomposition module is highly required. The proposed QR decomposition architecture is composed of Sign-Select Lookahead (SSL) coordinate rotation digital computer (CORDIC). In the SSL-CORDIC, the sign bits, which are computed ahead to select which direction to rotate, are used to select one of the last iteration results, therefore, the data dependencies on the previous iterations are efficiently removed. Our proposed QR decomposition module is implemented using TSMC 0.25 ${\mu}M$ CMOS process. Experimental results show that the proposed QR architecture achieves 34.83% speed-up over the Compact CORDIC based architecture for the 4 ${\times}$ 4 matrix decomposition.

• Journal of Korea Multimedia Society
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• v.22 no.10
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• pp.1149-1159
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• 2019

We present a novel deep learning architecture for obtaining a latent image from a single blurry image, which contains dynamic motion blurs through object/camera movements. The proposed architecture consists of two sub-modules: blur image restoration and optical flow estimation. The tasks are highly related in that object/camera movements make cause blurry artifacts, whereas they are estimated through optical flow. The ablation study demonstrates that training multi-task architecture simultaneously improves both tasks compared to handling them separately. Objective and subjective evaluations show that our method outperforms the state-of-the-arts deep learning based techniques.

• Journal of the Korean Institute of Landscape Architecture
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• v.36 no.1
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• pp.49-61
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• 2008

School forests, an important part of the urban forest, has diverse functions and plays an important role in artificial environment. It has three main functions: educational for children, ecological for nature, and cultural for residents. In spite of its diverse functions and roles, the actual conditions and achievements of school forests have not been correctly evaluated, resulting in institutional inertia. To improve these problems, this study was synthetically conducted by the post occupancy evaluation of users(residents, teachers and students) at school forests. This study can be summarized as follows: 1. The cognition and satisfaction level of school forests supported by private organizations was higher than those by local governments. Therefore, the establishment of a post management system of private organizations is more effective than the simple financial support of local governments. 2. The frequency of use of school forests by residents was higher than that of teachers. Their purposes were mainly to rest or walk However, teachers used school forests for nature observation and education. 3. In a survey of teachers about a reform measure and problems of school forests, the necessity of a post management system and financial security were significant requests. In addition, steady publicity and education, participant program, and incentives for teachers should be considered. This study is meaningful to systematically develop and activate the school forest movement. The integrated approach to the school forest movement reflects opinions of related users and is expected to become a useful foundation in studying about the improvement of city environments.

• Journal of the Korean Wood Science and Technology
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• v.51 no.1
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• pp.67-67
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• 2023