• Journal of Communications and Networks
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• v.12 no.2
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• pp.191-197
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• 2010

In this paper, we propose a novel methodology to identify border gateway protocol (BGP) updates associated with major events - affecting network reachability to multiple ASes - and separate them (statistically) from those attributable to minor events, which individually generate few updates, but collectively form the persistent background noise observed at BGP vantage points. Our methodology is based on principal component analysis, which enables us to transform and reduce the BGP updates into different AS clusters that are likely affected by distinct major events. We demonstrate the accuracy and effectiveness of our methodology through simulations and real BGP data.

• Journal of the Korean Statistical Society
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• v.24 no.2
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• pp.407-417
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• 1995

The h-plot is a graphical technique for displaying the structure of one population's variance-covariance matrix. This follows the mathematical algorithem of the principle component biplot based on the singular value decomposition. But it is known that the singular value decomposition is not resistant, i.e., it is very sensitive to small changes in the input data. In this article, since the mathematical algorithm of the h-plot is equivalent to that of principal component biplot of Choi and Huh (1994), we derive the resistant h-plot.

• Proceedings of the Korean Information Science Society Conference
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• 2002.10d
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• pp.70-72
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• 2002

컴포넌트 기반 구조의 프레임 워크인 샤모아 프레임 워크(Chamois Framework)는 다양한 컴포넌트 아키텍쳐중 COM(Component Object Model)과 Web Service로 개발되었다. 컴포넌트 기반 소프트웨어 개발(Component-Based Software Development)은 이미 작성된 소프트웨어 컴포넌트를 자신의 목적에 맞도록 재사용함으로써 여러 가지 위험 요소가 따를 수 있다. 따라서, 샤모아 프레임 워크에서 맞춤으로 변형된 컴포넌트에서 발생하는 오류를 테스트하기 위한 컴포넌트 맞춤 테스트 기법이 필요하다. 본 논문에서는 컴포넌트 맞춤 테스트 기법을 오류삽입 기반의 COM으로 확장하여 COM 컴포넌트 맞춤 테스트 기법을 샤모아 프레임 워크에 적용한 사례를 보인다.

• 한국IT서비스학회:학술대회논문집
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• 2003.05a
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• pp.584-590
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• 2003

CBSD의 핵심 연구 과제 중 하나인 컴포넌트 결합에 의한 응용 프로그램 개발에 대한 많은 연구가 진행되고 있지만 구체적 개발 환경에 대하여 아직 미비한 실정이다. 이에 본 논문에서는 CCM 컴포넌트들의 재귀적인 결합과 이에 기반을 둔 응용 프로그램 개발 방안을 제안하고자 한다. 이를 위해 컴포넌트 서비스의 기능적 결합을 기술하는 결합 명세서를 작성하고, 결합 명세서에 기반하여 컴포넌트를 결합하고자 한다. 또한 결합 컴포넌트의 결합성과 적합성을 검사하여 컴포넌트를 재구성하여 새로운 어플리케이션이나 컴포넌트를 자동으로 생성해 주는 응용 프로그램 개발 프레임웍을 제안하고자 한다.

• Journal of the Korean Data and Information Science Society
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• v.10 no.1
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• pp.163-172
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• 1999

We propose a cross-validatory method for the choice of the number of principal components in principal component regression based on the magnitudes of correlations with y. There are two different manners in choosing principal components, one is the order of eigenvalues(Shin and Moon, 1997) and the other is that of correlations with y. We apply our method to various data sets and compare results of those two methods.

• The KIPS Transactions:PartD
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• v.10D no.5
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• pp.753-762
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• 2003

Many Methodologies have proposed for component retrieval. Among them, thesaurus concept has introduced for similar component retrieval. This paper classified classes by concept according to inheritance relation for efficient retrieval of component, and applied fuzzy logic to thesaurus method and constructed object-oriented thesaurus. Proposed method could express category between concepts automatically, and calculate fuzzy degree between classes by comparing matching and mismatching degree to each class and category and construct thesaurus. Component retrieval is that using classes of component, candidate components are retrieved according to priority order using fuzzy similarity. Also, we improved retrieval performance by thesaurus greatly, setting critical of most suitable through simulation.

• Transactions of the Korean Society of Automotive Engineers
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• v.5 no.6
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• pp.13-27
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• 1997

In the modern design technology, a component should be designed to fit into the overall system performance. A design methodology is developed to expedite the mechan- ical design of complex mechanical systems, The relation between the system design and component design is defined by a top-down approach and the results from the system design are utilized in the component design process. As a design example, an automobile exhaust system is selected for the system design and a bellows is chosen for a component design. Design methodology based on the top-down approach consists of five steps; (1) Analysis of service load, (2) Development of a lumped parameter, (3) Completion of the system design, (4) Selection of the component topology, (5) Completion of the component design, A method using a equivalent matrix is developed in order to determine unknown external forces in linear structural analyses. The bellows is also analyzed by the finite element method using a conical frustum shell element. Various experiments are performed to verify the developed theories. The top-down desi- gn approach is demonstrated by a design case using structural and shape optimization technology. Since the method is relatively simple and easy compared to other methods, it can be applied to the general design where system and component designs are involves simultaneously.

• Journal of Internet Computing and Services
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• v.7 no.6
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• pp.1-10
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• 2006

A software development using components reuse is an useful method to reduce the software development cost. But a retrieval method by the keyword and category classifications is difficult to search an exact matching component due to components complexity in component reuse. Therefore, after different existing methods are examined and analyzed, an effective classification and retrieval method using XML specifications and the system architecture of components integrated management based on it are presented. Many discording elements of DTD which is component meta-expression exist in components retrieval. To compensate it, this retrieval method using estimations of precision and concision is effective one to catch considerable matching preference components. This method makes possible to retrieve suitable components having better priority due to searching similar matching components that are difficult in an existing keyword matching method.

• Journal of KIISE:Computing Practices and Letters
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• v.6 no.6
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• pp.601-607
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• 2000

Runtime updating of component is a technology which is replacing component used in program with newly implemented component without terminating running program using old one. Recently, it is trend that softwares are developed by reusing the existing component. When we use these components to softwares which have to offer consecutive services, they must be terminated or shutdown to update component with newly implemented one. In this case, users who are offered services of software have to request them one more time and sometimes lose informations which they use. Therefore, this paper suggests how to update components with newly implemented one without terminating tbe running software wbicb is cmnposed witb tbe component for tbe purpose of solving problems which are occurred wben existing components are being ubdated.

• Journal of Electrical Engineering and Technology
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• v.9 no.2
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• pp.755-761
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• 2014

Heterogeneous components have different component models, which prevents such components from sharing the functionalities of other components based on the different models. As one of methods for linking heterogeneous components, this paper suggests a proxy component to construct a bridge between heterogeneous components of OPRoS (Open Platform for Robotic Service) and RTM (Robot Technology Middleware). The proxy component consists of two types of components called Adaptor and Interceptor, via which the heterogeneous components can exchange data and services easily. The proposed method enables adaptor and interceptor components to directly invoke the services of the latter and the former, respectively, in order to exchange data and services on a real-time basis. The proxy component can be implemented for OPRoS and RT (Robot Technology) component models to connect with RT and OPRoS ones, respectively. It is shown through a simple experiment that the proposed method works well for real-time control.