• Smart Structures and Systems
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• v.31 no.2
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• pp.155-169
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• 2023

The quasi-static component of the moving vehicle-induced dynamic response is promising in damage detection as it is sensitive to bridge damage but insensitive to environmental changes. However, accurate extraction of quasi-static component from the dynamic response is challenging especially when the vehicle velocity is high. This paper proposes an adaptive quasi-static component extraction method based on the modified variational mode decomposition (VMD) algorithm. Firstly the analytical solutions of the frequency components caused by road surface roughness, high-frequency dynamic components controlled by bridge natural frequency and quasi-static components in the vehicle-induced bridge response are derived. Then a modified VMD algorithm based on particle swarm algorithm (PSO) and mutual information entropy (MIE) criterion is proposed to adaptively extract the quasi-static components from the vehicle-induced bridge dynamic response. Numerical simulations and real bridge tests are conducted to demonstrate the feasibility of the proposed extraction method. The results indicate that the improved VMD algorithm could extract the quasi-static component of the vehicle-induced bridge dynamic response with high accuracy in the presence of the road surface roughness and measurement noise.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.844-848
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• 2004

We evaluate the durability of vehicle chassis component under dynamic loadings. Since the fatigue analysis of vehicle component is based on the dynamic load history it must be done by dynamic analysis. But in case the vehicle component has natural frequencies much larger than reversing frequencies of load history, we can get small analysis errors by applying quasi-static analysis. So it is inefficient that we apply to the dynamic analysis for all the vehicle components. In this research, we discuss the quasi-static analysis method which is appropriate for the fatigue analysis. And in case we can only perform the fatigue analysis based on dynamic analysis, we introduce more efficient method in the analysis time and hard disk storage.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.35 no.6
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• pp.548-555
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• 2007

Typical helicopter simulation programs rely on differential equations of a closed form. However, since these equations are derived using various assumptions, their usefulness is limited to small flight regions and specific model types. This paper presents a component based rotorcraft simulation program. The program adopts methods of multi-body dynamics and is written in an object-oriented programming language. The program was validated using an AH-1G helicopter simulation. The trim results are well matched with flight test data. It is also shown that program is capable of running in real-time on a desktop computer.

• Proceedings of the Korea Multimedia Society Conference
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• 2002.11b
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• pp.396-399
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• 2002

현재의 컴포넌트기반 개발(CBD:Component Based Development)을 통한 비즈니스 영역의 개발과 응용에 많은 연구가 진행되고 있다. 기업이나 조직은 분산환경을 통한 비즈니스 기능의 확대와 통합을 빠르고 효과적인 방법을 요구하고 있다. 에이전트는 분산환경의 유연한 서비스를 제공하고, 컴포넌트 기술은 개발의 효율성을 보장함으로써 이러한 요구를 해결할 수 있다. 본 논문에서는 비즈니스 영역에 대한 에이전트의 효과적인 개발과 적용을 위해 e-비즈니스 에이전트지향 컴포넌트기반 개발 프로세스(ebA-CBD:e-business Agent oriented Component Based Development)를 통해 ebA의 명세와 ebA 개발을 위한 컴포넌트 명세를 제안한다. 특히, e-비즈니스 에이전트의 식별과 명세를 위해 ebA-CBD 매트릭스, ebA Architecture Model과 ebA-Spec.을 제시하며, 사례를 통해 명세의 이해성 및 사용성을 제공하고자 한다.

• Journal of Microbiology and Biotechnology
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• v.27 no.6
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• pp.1106-1111
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• 2017

Escherichia coli was engineered to sense methanol by employing a chimeric two-component system (TCS) strategy. A chimeric MxaY/EnvZ (MxaYZ) TCS was constructed by fusing the Paracoccus denitrificans MxaY with the E. coli EnvZ. Real-time quantitative PCR analysis and GFP-based fluorescence analysis showed maximum transcription of ompC and the fluorescence at 0.01% of methanol, respectively. These results suggested that E. coli was successfully engineered to sense methanol by the introduction of chimeric MxaYZ. By using this strategy, various chimeric TCS-based bacterial biosensors can be constructed and used for the development of biochemical-producing recombinant microorganisms.

• Proceedings of the Korea Multimedia Society Conference
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• 2001.06a
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• pp.317-320
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• 2001

SECOS(SoonChunHyang E-Commerce System)는, CBD(Component Based Development) 방식에 따라 개발된 컴포넌트들을 이용하여 새로운 응용 시스템을 개발하는 CBSD(Component Based Software Development)기법을 이용하여 구축된, 웹 기반 정보활용의 전형적 모델을 제공키 위한 개방형 프레임워크에 기반을 둔 소프트웨어 시스템이다. 현재 본 연구팀은 SECOS의 적용 사례로서 B-to-C 기반 E-Business를 위한 쇼핑몰을 구축하고자, 검색 및 지불 그리고 응용분야의 S/W 컴포넌트들을 개발 중에 있다. 본 논문에서는 전체적인 SECOS 의 구성에 대한 이해를 돕고자, SECOS의 내부구조 및 그에 따른 컴포넌트들 그리고 그들간의 상호관련에 대하여 설명하고 있으며, 아울러 새로운 쇼핑몰 구축시, SECOS의 프레임워크 및 컴포넌트들을 활용하기 위한 방안에 대해 살펴보고자 한다.

• Proceedings of the Korea Information Processing Society Conference
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• 2002.11c
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• pp.1961-1964
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• 2002

현재의 소프트웨어 개발 패러다임은 전체 시스템에서 독립적인 업무 또는 기능을 수행하는 단위이고 유지보수에 필요한 교체 가능한 모듈로 재사용성과 대치성을 제공하는 컴포넌트기반 개발(CBD:Component Based Development)이 연구되고 있다. 기업이나 조직은 웹을 통한 비즈니스 기능의 확대에 따른 효과적이고 빠른 개발과 적용을 요구함에 따라, 에이전트를 통한 유연한 서비스를 제공하고자 한다. 본 논문에서는 비즈니스 영역에 대한 에이전트의 효과적인 개발과 적용을 위해 컴포넌트, e-비즈니스 에이전트, 자원, 관리 관점을 고려하여, e-비즈니스 에이전트지향 컴포넌트기반 개발 프로세스(ebA-CBD:e-business Agent oriented Component Based Development)를 제안한다. 특히, e-비지니스 에이전트의 식별과 명제를 위해 ebA-CBD 매트릭스, ebA Architecture Model과 ebA-Spec.을 제시하며, 사례를 통해 프로세스의 이해성 및 사용성을 제공하고자 한다.

• Journal of the Korea Society of Computer and Information
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• v.9 no.2
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• pp.19-26
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• 2004

This paper proposes ACA (Adaptive Component Analysis) as a method for feature extraction and analysis of the content-based image retrieval system. For satisfactory retrieval, the features extracted from images should be appropriately applied according to the image domains and for this, retrieval measurement is proposed in this study. Retrieval measurement is a standard indicating how important the value of a relevant feature is to image retrieval. ACA is a middle stage for content-based image retrieval and it purposes to improve the retrieval speed and performance.

• Asia pacific journal of information systems
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• v.12 no.2
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• pp.163-178
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• 2002

With the spread of electronic commerce, Internet auction systems have become widely used, because they overcome the spatial and the temporal limitations of traditional auction systems. However, most of current Internet auction systems have many shortcomings such as support for limited auction types, difficulty in registering items, maintenance problems, etc. This paper designs and implements a component-based seller-driven Internet auction system, which complements those traditional auction systems as follows: It allows sellers to select one of the auction types they want by answering questions which eventually lead to a specific auction type; Since it implements five basic auction types according to the principles of component-based development, it is easy to implement diverse types of auction systems with a slight modification to existing components. Further, the use of DAO concept makes it easy to use various commercial database systems.

• Proceedings of the Korea Society for Simulation Conference
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• 2004.05a
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• pp.136-140
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• 2004

A power-plant simulation tool has been developed for training the plant operators and testing a plant control system. The simulation tool is composed of a graphic editor, a component model builder and a system simulation solver. Such new programing techniques as object-oriented modeling and GUI(Graphical User Interface) are employed in developing the simulation tool. The graphic editor is based on the OpenGL library for effective implementation of GUI while the component model builder is based on object-oriented programming for efficient generalization of component models. The developed tool has been verified through the simulation of a real power plant.