• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.59 no.9
• /
• pp.1549-1559
• /
• 2010

Modern power system is operated and managed in closed network environment with treating a great variety of data, and requirement of real time power system data is more increasing. However, it is difficult for operators to fast evaluate the condition of power system using only isolation network system such as SCADA or EMS regarding unexpecting situations occurring. Recent technology achievement in areas of distributed computing, networking high speed communications and digital control as well as the availability of accurate GPS time source are rapidly becoming the enabling factors for the development of a new generation of real time power grid monitoring tools. In this paper, architecture of WAMAC which is the wide area monitoring and control system not only to control but also to monitoring in real time is proposed and the plan of integration interface with legacy system such as EMS for providing power system analysis base data effectively is suggested.

• The Journal of the Korea Contents Association
• /
• v.8 no.11
• /
• pp.57-64
• /
• 2008

The data grid computing provides geographically distributed storage resources to solve computational problems with large-scale data. Unlike cache replacement policies in virtual memory or web-caching replacement, an optimal file replacement policy for data grids is the one of the important problems by the fact that file size is very large. The traditional file replacement policies such as LRU(Least Recently Used), LCB-K(Least Cost Beneficial based on K), EBR(Economic-based cache replacement), LVCT(Least Value-based on Caching Time) have the problem that they have to predict requests or need additional resources to file replacement. To solve theses problems, this paper propose SBR-k(Sized-based replacement-k) that replaces files based on file size. The proposed policy considers file size to reduce the number of files corresponding to a requested file rather than forecasting the uncertain future for replacement. The results of the simulation show that hit ratio was similar when the cache size was small, but the proposed policy was superior to traditional policies when the cache size was large.

• The Journal of the Korea Contents Association
• /
• v.12 no.2
• /
• pp.19-29
• /
• 2012

Currently, cloud computing technology is being supplied in various service forms and it is becoming a ground breaking service which provides usage of storage service, data and software while user is not involved in technical background such as physical location of service or system environment. cloud computing technology has advantages that it can use easily as many IT resources as it wants freely regardless of hardware issues required by a variety of systems and service level required by infrastructure. Also, since it has a strength that it can choose usage of resource about business model due to various internet-based technologies, provisioning technology and virtualization technology are being paid attention as main technologies. These technologies are ones of important technology elements which help web-based users approach freely and install according to user environment. Therefore, this thesis introduces software-related technologies and architectures in an aspect of grid for building up high availability cloud computing environment by analysis about cloud computing technology trend.

• Proceedings of the Korea Contents Association Conference
• /
• 2008.05a
• /
• pp.517-520
• /
• 2008

This paper implements the graphic service template authoring tool based on the service template object model of describing the meta information of the services in the semantic web service environment. Our proposed system provides the robot services by constructing web services automatically and making the appropriate service plans. Moreover, it can create, append, delete, and update the service templates of URC based on STDL, and provide the graphic function on service template resources. In order to provide the user friendly environment in the service template phase, we implement the various editing environment : flow view style, grid view style, and text view style. We also provide the easy editing function by realizing abstract service block based on the robot API. Finally we can offer the intelligent and autonomous service of service agent based on semantic information.

• Journal of Software Engineering Society
• /
• v.23 no.4
• /
• pp.151-163
• /
• 2010

In the defense software domain where large-scale software products in various application areas need to be built, reusing software is regarded as one of the important practices to build software products efficiently and economically. There have been many efforts to apply various methods to support software reuse in the defense software domain. However, developers in the defense software domain still experience many difficulties and face obstacles in reusing software assets. In this paper, we analyze practical problems of software reuse in the defense software domain, and define core requirements to solve those problems. To meet these requirements, we are currently developing the Component Grid system, a reuse-support system that provides a developer-centric software reuse environment. We have designed an architecture of Component Grid, and defined essential elements of the architecture. We have also developed the core approaches for developing the Component Grid system: a semantic-tagging-based requirement tracing method, a reuse-knowledge representation model, a social-network-based asset search method, a web-based asset management environment, and a wiki-based collaborative and participative knowledge construction and refinement method. We expect that the Component Grid system will contribute to increase the reusability of software assets in the defense software domain by providing the environment that supports transparent and efficient sharing and reuse of software assets.

• Journal of KIISE:Computing Practices and Letters
• /
• v.14 no.9
• /
• pp.841-849
• /
• 2008

Natural disaster such as inundation due to the typhoon induced storm-surge has inflicted severe losses on the coastal area. The problem of global warming and sea surface rising has issued and thus influences the increase of frequency and potential power of storm-surge. What we can do is to make intelligent effort to predict and prevent the losses through the early warning and prevention activity from the accurate prediction and forecasting about the time-varying storm-surge height and its arriving time resulted from the numerical simulation with sea observations. In this paper, we developed the web service based GIS-Enabled storm-surge visualization system to predict and prevent the storm-surge disasters. Moreover. for more accurate topography around coastal area and fine-grid storm-surge numerical model, we have accomplished GIS-based coastal mapping through LiDAR measurement.

• 전자공학회논문지 IE
• /
• v.47 no.1
• /
• pp.56-60
• /
• 2010

The widespread development of IT, growth of Web 2.0 application, the proliferation of personal hand held devices with access to the internet, and the availability of wireless networks, each have played an important role in creating the cloud computing model. Cloud computing is a business model and new trend of web application technology. The term is often used in the same context as grid computing or utility computing. In the cloud computing environment, we are able to use the same all of hardware resources in the server and share information easily. In this paper, we aimed a study to apply e-learning part to cloud computing environment. For this purpose, we proposed an application of LMS and LCMS based e-learning in the cloud computing environment. So LMS including LCMS connected to data center of cloud computing.

• Proceedings of the Korean Information Science Society Conference
• /
• 2005.11a
• /
• pp.1039-1041
• /
• 2005

가상 풍동 실험은 슈퍼컴퓨터와 같은 고성능의 계산 지원과 실험을 위한 깊은 지식을 요구하여 실험을 수행하는데 많은 어려움이 수반된다. 그리드[1][2]는 산재한 자원을 연계하여 고성능 응용을 위해 효율적으로 활용할 수 있도록 하는 기반구조를 제공한다. 본 논문에서는 그리드 자원을 활용하여 가상 풍동 실험을 빠르고 효과적으로 수행할 수 있는 그리드 웹 포탈 서비스를 제안한다. 통합된 포탈 서비스를 통하여 사용자의 응용 및 실험환경의 요구사항을 반영한 격자생성, 계산 작업, 작업 모니터링, 결과 가시화를 효율적으로 수행한다.

• Electronics and Telecommunications Trends
• /
• v.22 no.1 s.103
• /
• pp.24-36
• /
• 2007

2006년 9월 개최된 제18차 GGF 회의는 그리드 연구에 대한 새로운 출발점으로 기억될 것이다. 1999년 미국 시카고 대학의 이안 포스터 교수에 의해서 “인터넷 망을 이용하여 분산된 컴퓨터 자원의 결합을 통한 작업 수행”이 가능한 그리드가 처음으로 제안된 이후, 많은 기술 발전을 거듭하였고, 최근에는 웹서비스 기술과 그리드 기술을 접목한 개방형 그리드 서비스 구조를 제안하였다. 제18차 회의는 현재까지 개발된 그리드 기술에 본격적으로 웹서비스 기술을 도입하기 위한 선포였으며, 이에 GGF를 OGF로 개명하였다. 본 고에서는 OGSA에 대한 분석을 기반으로 그리드 웹서비스에 대해서 간략히 소개하고, 현재 그리드 웹서비스에서 보안 서비스를 제공하기 위해 연구를 진행하고 있는 웹서비스 보안 기술과 이에 대한 적용 동향을 살펴본다.

• Proceedings of the Korea Society of Information Technology Applications Conference
• /
• 2005.11a
• /
• pp.1-6
• /
• 2005

The purpose of this paper is to propose a novel modeling approach called Services Ecosystem that applies the concept of ecosystems in ecology to Service-Oriented Software Development and Integration. For this purpose, an ecological system for software systems is proposed for the emerging Service-Oriented Computing paradigm, describing how participants interact with each other within their environments. Three emerging concepts, Service-Oriented Programming, Software Factories, and Service Grid, are employed to explain biotic and abiotic environments. Based upon the Services Ecosystem model, we demonstrate Services Ecosystem Model transformations by using a case example. The Services Ecosystem model is a novel approach for envisioning the Service-Oriented Computing paradigm in terms of an ecosystem in which the roles/perspectives of each participant and their relationships/interactions to environments are clearly described with a holistic view.