• Korean Journal of Computational Design and Engineering
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• v.5 no.1
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• pp.71-78
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• 2000

The growths of the World Wide Web and the advances in high-speed network access have greatly changed existing CAD/CAE environment. The m has enabled us to share various distributed product data and to collaborate on a design work. An international standard for the product model data, STEP, and a standard fur the distributed object technology, CORBA, are becoming very important components in the advanced design and manufacturing environment. These two technologies provide background for the sharing of product data and the integration of applications on the network. This study describes a prototype CAD/CAE environment that is integrated on the network by STEP and CORBA. Several application servers servers and client software were developed to verify the proposed concept.

• Korean Journal of Computational Design and Engineering
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• v.5 no.1
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• pp.79-87
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• 2000

This paper presents an integrated but open product development environment for distributed and collaborative design. The web-based framework, called DOME, allows designers to build integrated models using both local and distributed resources, and to collaborate by exchanging services in a network-centric product development environment. Thus, an integrated model can be created while each participant focuses on his or her own area of expertise. A design problem model is created by connecting modules, which represent specific system components, analysis capabilities/software, disciplines, or organizations relevant to the problem. The modules interact with each other using service exchanges based upon the CORBA standard communication protocol. The goal of this framework is tall provide the ability to rapidly construct integrated design problem models to facilitate collaborative design work, improve product quality and reduce development time. Ultimately, it should allow specialized engineering applications and design problem models to operate under a common design environment.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.1
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• pp.56.3-56.3
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• 2018

The present study formulates the theory of spontaneously emitted electromagnetic fluctuations in magnetized plasmas containing particles with an anisotropic suparthermal (bi-Kappa) velocity distribution function. The formalism is general applying for an arbitrary wave vector orientation and wave polarization, and for any wave-frequency range. As specific applications, the high-frequency electromagnetic fluctuations emitted in the upper-hybrid and multiple harmonic electron cyclotron frequency range are evaluated. The fluctuations for low-frequency are also applied, which include the kinetic $Alfv\acute{e}n$, fast magnetosonic/whistler, kinetic slow mode, ion Bernstein cyclotron modes, and higher-order modes. The model predictions are confirmed by a comparison with particle-in-cell simulations. The study describes how energetic particles described by kappa velocity distribution functions influence the spectrum of high and low frequency fluctuations in magnetized plasmas. The new formalism provides quantitative analysis of naturally occurring electromagnetic fluctuations, and contribute to an understanding of the electromagnetic fluctuations observed in space plasmas, where kappa-distributed particles are ubiquitous.

• Proceedings of the KIEE Conference
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• 2006.04a
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• pp.297-299
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• 2006

Many distributed applications is developed in various environment such as operating system, software platform. So, they exhibit different types of system behavior, status, during the course of their operation. Each such behavior may have different functional and non-functional requirements. Therefore, many distributed application need to fault-tolerance solution. Personal robot provide various service or application. Because personal robot has many application or service, it need to fault-tolerance architecture. A flexible architecture is required to provide dependability. In this paper, it is suggested a fault-tolerant architecture for module-based personal robot with module fault-tolerance, service fault-tolerance.

• Journal of Korea Society of Digital Industry and Information Management
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• v.7 no.1
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• pp.11-18
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• 2011

A mobile agent system is the most common software paradigm for distributed applications. A software development model to develop efficiently for these systems is needed. Unified Modeling Language (UML) is a widely used software development model to develop a system for Visualizing, Specifying, Constructing, Documenting. However, UML can not describe in explicit way the necessary mobility of the mobile agent-based software systems. In this paper, the interaction diagrams of UML (sequence diagrams and communication diagrams) are extended and used to express the mobility of the mobile agents in three ways. For a case study, we applied the extended diagrams to a distributed file searching using mobile agents, and showed these diagrams can describe the mobility very well.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1998.10a
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• pp.53-60
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• 1998

Efficiency of design process for large scale structures highly depends on the development of efficient structural analysis and structural response control algorithms because a successful design involves a number of structural analysis based on iterative structural response control process. In this paper, distributed structural analysis model on multiple personal computers connected by ethernet network is presented. To reduce communication cost required in the process of analysis, substructuring techniques are adopted to evenly distribute computational loads on each processor. With its applications on structural analysis of plane frame structures, performance of the proposed computational model are presented in detail.

• Korean Journal of Computational Design and Engineering
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• v.12 no.4
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• pp.233-244
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• 2007

Web Services are a distributed component technology based on XML and Web. The Web Services are used to integrate heterogeneous systems under the distributed environment. In this study, the concept of Web Services for CAD (WSC) is introduced, which aims at interoperation with CAD systems using the Web Services. This paper introduces one part of the WSC which enables remote users or applications to retrieve the geometries and the design history of CAD models using the Web Services. This paper proposes an architecture of the WSC, the data model and the interfaces for retrieving CAD model information, and the way to apply the WSC to commercial CAD systems.

• Journal of the Korea Society for Simulation
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• v.12 no.4
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• pp.103-111
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• 2003

A distributed sewer cluster system is a cost-effective system to provide a service application for clients with reliable, scalable, available, and fault-tolerant features. In order to provide high quality services, it is necessary to evaluate service performances, tune the server system, and analyze performances. In this paper, we propose a simulator to generate workloads based on statistic configuration according to estimated application traffics, apply workload scheduling algorithms, and evaluate the simulation results. We introduce the simulator design modelling and architecture. By using flexible parameters, the simulator is able to generate various patterns of workloads with different statistics, and configure system environments such as the number of server nodes, system resources considered, and their capacities. With this simulator, we introduce two scenarios: one is to find appropriate thresholds for the best performance of cluster system, and the other is to find the suitable scheduling algorithm for workload characteristics of service applications.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.57 no.1
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• pp.30-35
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• 2008

In this paper, the application of power Quality monitoring based on Sampled Value(SV) which is introduced in the IEC61850 International Standard for substation communication are discussed. Firstly, while Merging Unit(MU) is designed as a process level device transmitting sensor data, the practical problems such as time delay compensation and optical fiber communication are encountered. Secondly, the Sampled Value message which is proper to a power quality monitoring system is presented. Because the power quality monitoring system requests less time-critical service compared to protection and control applications, the Sampled Value service message structure is introduced to improve efficiency. Lastly, the power quality monitoring server having various power quality analysis functions is suggested to verify the performance of Merging Unit With the diverse experiments, it is proved that the process bus distributed solution is flexible and economic for the power quality monitoring.

• ETRI Journal
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• v.34 no.3
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• pp.462-465
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• 2012

This letter proposes a new distributed scheduling scheme combined with routing to support the quality of service of real-time applications in wireless mesh networks. Next, this letter drives average end-to-end delay of the proposed scheduling scheme that sequentially schedules the slots on a path. Finally, this letter simulates the time division multiple access network for performance comparison. From the simulation results, when the average number of hops is 2.02, 2.66, 4.1, 4.75, and 6.3, the proposed sequential scheduling scheme reduces the average end-to-end delay by about 28%, 10%, 17%, 27%, and 30%, respectively, compared to the conventional random scheduling scheme.