• Convergence Security Journal
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• v.2 no.2
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• pp.179-187
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• 2002

Grid is a infrastructure to connect heterogeneous resources that are scattered over areas with high-speed network and to cooperate with each other. To carry out Grid application, first, network resources should be managed, since the network has to be safe and reliable. GMA suggests an effective architecture for monitoring of resources that are scattered over a wide area. In this paper, basing on GMA, Grid network management system based on web for practical and general network management is designed. Grid network management system has to operate and connect various distributed management system. Using LDAP authentication, as one access system, Grid network management system maintain stability.

• Proceedings of the KIEE Conference
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• summer
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• pp.572-574
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• 2004

The configuration of Distribution Automatic System(BAS) is dual servers and raid 5(redundant arrays of inexpensive disks) clustering dual HDD. The DAS has the distributed object-oriented architecture using middleware software(BASEstar), so the number of client nodes has no limitation. Because the DAS is scalable, it can be configured using various application programs and be upgraded easily. The DAS has competitive to export because there are system development and accumulation of technology that coincide in International Standard, using common 05 and DB. This paper describes the structure of DAS hardware and software separately and proposes to improve program to share real time DB efficiently at each node.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.52 no.6
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• pp.365-371
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• 2003

Input queued switch is useful for high bandwidth switches and routers because of lower complexity and fewer circuits than output queued. The input queued switch, however, suffers the HOL-Blocking, which limits its throughput to 58%. To overcome HOL-Blocking problem, many input-queued switch controlled by a scheduling algorithm. Most scheduling algorithms are implemented based on a centralized scheduler which restrict the design of the switch architecture. In this paper, we propose a simple scheduler called Pipelined Round Robin (PRR) which is intrinsically distributed by each input port. We presents to show the effectiveness of the proposed scheduler.

• Proceedings of the KIEE Conference
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• 2004.07d
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• pp.2522-2524
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• 2004

최근 P2P 시스템에 대한 연구는 매우 활발하게 진행되고 있다. 그 중 P2P 시스템의 자원 공유에 관한 문제는 매우 중요하게 다루어지며, 또한 많은 연구가 진행되고 있다. 본 논문에서는 분산된 컨텐츠 기반의 자원 공유를 위해 각각의 노드들을 계층별로 분류하도록 하였으며, 레이어 별로 차별적인 서비스를 제공하도록 하였다. 시스템의 특징은 다음과 같다. 먼저, 노드를 성능에 따라 레이어 별로 분류하며, 효율적인 자원 공유를 위해 노드들을 그룹화 한다. 클러스터링을 통해 상위 레이어에 속한 노드들과 자원을 공유할 수 있도록 한다.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.109.6-109
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• 2001

This paper suggests a new industrial automation system architecture which adopts the Real-Time CORBA as a solution for the recently emerging problems, such as cost eciency, interoperability with different networks, software productivity, etc. This paper shows how the adoption of RT-CORBA helps end-users to improve software productivity in the heterogeneous distributed system integrate eldbus with different kinds of network easily and lower the cost of hardware medication and extension, Finally, CRECO - a real- time CORBA which is in development and suited to industrial automation system - is introduced. RT-Linux and Probus - two major components while implementing the CRECO - are dealt with primarily.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.178.2-178
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• 2001

Today, many electronic devices and ECUs (Electronic Control Units) are used in the automotive body control systems. It becomes more common that these devices exchange data with others through an in-vehicle network. Automobile manufacturers concentrate their efforts on development of body control systems based on networks in order to save cost and to increase flexibility and safety. OSEK/VDX has been founded as a joint project in German and French automotive industry aiming at an industry standard for an open-ended architecture for distributed control units in vehicles OSEK/VDX consists of Communication (specification of data exchange within and between control units), Network Management specification of Configuration determination and monitoring and Operating System (specification of realtime executive for ECU software ...

• The Magazine of the IEIE
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• v.25 no.2
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• pp.48-57
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• 1998

본 기고는 시뮬레이션 기술 분류 중 Virtual Simulation, 그 중에서도 항공기 시뮬레이터 기술에 초점을 맞추고자 한다. 항공기 시뮬레이터 기술이 시뮬레이션 전체 분야에서 차지하는 비중과 현재의 위를 객관적으로 이해하기 위하여 시뮬레이션 기술이란 무엇인가 하는 원론에서부터 출발한다. Virtual, Constuctive, Live 등의 시뮬레이션 기술들을 간략히 소개하면 이들 기술의 변천을 SIMNET(SIMulator NETworking), DIS(Distributed Interative Simulation), ALSP(Aggregate Level Simulation Protocol), HLA(High Level Architecture) 등의 프로그램 등을 통하여 살펴본다. 항공기 시뮬레이터 기술은 Virtual 시뮬레이션 기술의 발원으로서 1930년대 이후로 시뮬레이션 기술 전반을 선도하여 왔는데, 그 진화과정을 간추려 언급한다. 또한, 항공기 시뮬레이터를 구현하기 위한 기술들을 간략히 살펴보고, 그 기술들을 선도하는 네덜란드 Delft 대학의 SIMONA(SImulation, MOtion and NAvigation) 프로그램과 미국 국방성, 산업체, 학계, 연구소 등을 중심 축으로 하는 NCS(National Center for Simulation)를 소개함으로써 항공기 시뮬레이터는 물론, 시뮬레이션 기술 전반의 미래를 가늠한다. 마지막으로 항공기 시뮬레이터를 중심으로 하는 국내 시뮬레이터 기술 수준과 산업 현황을 간추려 소개한다.

• Steel and Composite Structures
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• v.20 no.5
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• pp.1043-1066
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• 2016

A new analytical solution based on a third order shear deformation theory for the problem of static analysis of cross-ply doubly-curved shells is presented. The boundary-discontinuous generalized double Fourier series method is used to solve highly coupled linear partial differential equations with the mixed type simply supported boundary conditions prescribed on the edges. The complementary boundary constraints are introduced through boundary discontinuities generated by the selected boundary conditions for the derivation of the complementary solution. The numerical accuracy of the solution is compared by studying the comparisons of deflections, stresses and moments of symmetric and anti-symmetric laminated shells with finite element results using commercially available software under uniformly distributed load. Results are in good agreement with finite element counterparts. Additional results of the symmetric and anti-symmetric laminated and sandwich shells under single point load at the center and pressure load, are presented to provide data for the unsolved boundary conditions, benchmark comparisons and verifications.

• Structural Engineering and Mechanics
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• v.48 no.2
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• pp.241-255
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• 2013

The receding contact problem for two elastic layers whose elastic constants and heights are different supported by two elastic quarter planes is considered. The lower layer is supported by two elastic quarter planes and the upper elastic layer is subjected to symmetrical distributed load whose heights are 2a on its top surface. It is assumed that the contact between all surfaces is frictionless and the effect of gravity force is neglected. The problem is formulated and solved by using Theory of Elasticity and Integral Transform Technique. The problem is reduced to a system of singular integral equations in which contact pressures are the unknown functions by using integral transform technique and boundary conditions of the problem. Stresses and displacements are expressed depending on the contact pressures using Fourier and Mellin formula technique. The singular integral equation is solved numerically by using Gauss-Jacobi integration formulation. Numerical results are obtained for various dimensionless quantities for the contact pressures and the contact areas are presented in graphics and tables.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.38 no.12
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• pp.58-66
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• 2001

Input queueing is useful for high bandwidth switches and routers because of lower complexity and fewer circuits than output queueing. The input queueing switch, however, suffers HOL-Blocking, which limits the throughput to 58%. To get around this low throughput, many input queueing switches have centralized scheduler, which centralized scheduler restrict the design of the switch architecture. To overcome this problem, we propose a simple scheduler called PRR(Pipelined Round Robin), which is intrinsically distributed and presents to show the effectiveness of the proposed scheduling.