• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.3
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• pp.643-651
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• 1996

In this paper, to provide the possibility of various multimedia services, especially the collaborative work using the centralized control feature of the Service Node, is studied. We focused on the telewriting as the upper layer application to confirm the basic functions of the collaborative work. For this, we implement and add telewriting collaborative work function to the Service Node emulator, and terminals operating in the Windows environment are also developed. Through the tests on the system, we verify the basic functions related to the collaborative work are performed adequately, and confirm the concept of Service Node can support various type of multimedia conference services.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.12C
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• pp.1228-1237
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• 2002

Network management is composed of five major functional areas, fault, configuration, account, performance and security management in the ITU standards. Configuration management identifies, exercises control over, collects data from network element node system and provides data to the management systems. The proposed architecture is designed based on the Distributed Processing Environment of CORBA(Common Object Request Broker Architecture) Spec v2.3. In this paper, configuration management system has been designed and implemented with layered managed object. It provides that integrated management of various data link layer technology. We suggest MIB(Management Information Base)/MIT(Management Information Tree) to support integrated management and distributed environment.

• Journal of Communications and Networks
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• v.4 no.4
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• pp.336-343
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• 2002

A major challenge for next generation mobile communication is capturing the system architecture’s complexity with all its internal and external dependencies. Seamless integration of heterogeneous environments in all system parts is a key requirement. Moreover, future systems have to consider the different evolution cycles of individual system parts. Among those, services are expected to change the fastest. With respect to these considerations, we propose an overall architecture for next generation mobile communication systems. It covers all system parts from wireless transmission to applications including network and middleware platform. Our approach focuses on adaptability in terms of recon- figurability and programmability to support unanticipated system evolution. Therefore, we consider abstraction layers which consist of adaptable cooperating components grouped by open platforms rather than rigid system layers. In addition to that, we introduce cross-layer cooperation allowing an efficient use of the available resources. Specific scenarios illustrate the feasibility of our approach.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.8A
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• pp.802-812
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• 2007

A Fast handover protocols for Mobile IPv6 networks can support seamless service by reducing handover latency to mobile nodes. To gain advantage derived from the fast handover in IEEE 802.16e networks, we propose a new fast handover protocol using a multiple simultaneous binding mechanism and a handover protocol based on trigger event for IEEE 802.21 in order to integrate IEEE 802.16e handover protocol and FMIPv6 handover protocol using link layer trigger. Through the numerical analysis, we compare performance of the proposed protocol and FMIPv6 protocol.

• Proceedings of the KIEE Conference
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• 1997.07d
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• pp.1255-1257
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• 1997

In order to obtain key technologies for a kW class internal humidifying proton-exchange-membrane fuel cell (PEMFC) a single cell with a large electrode area has been designed and manufactured and the performance of large area membrane/electrode assemblies (MEAs) has been evaluated by using the single cell. A small area MEA made of commercial E-TEK electrode and Nafion 117 membrane showed a performance of 0.7V, $300mA/cm^2$ whereas large area MEA made of catalyst layer on carbon support and Nafion 117 showed a lower performance. To improve the performance of large MEA direct coating of catalyst was carried out on the membrane using a screen printer.

• Proceedings of the KIEE Conference
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• 1997.07d
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• pp.1308-1310
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• 1997

Several methods for electrode fabrication of phosphoric acid fuel cell(PAFC) have been studied. The conventional methods that include a coating method and a rolling method, have disadvantages of a very complicated drying process and a hot pressing process for making a large electrode. In this study, to solve these problems, the mixing method of coating and rolling processes has been developed. In the mixing method, the electrode was coated on the electrode support and, after drying the coated layer, was rolled at room temperature and then sintered at $350^{\circ}C$. The single cell performances of the electrodes fabricated by several methods were examined and the mixing method appeared a good cell performance of 0.65 V, $260\;mA/cm^2$. Also the single cell with an area of $2000\;cm^2$ was manufactured and its performance attained 0.593 V, 300 A.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.1542-1549
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• 2009

The function of subgrade in the railway is to support track load on the subgrade as well as train load. Unlike the traditional railway, the uppermost subgrade layer in the Gyeongbu high speed railway was constructed as the reinforced road bed. The reinforced road bed comprises sub-ballast in the upper part and grade ballast in the lower part. The filling material such as soil and rocks in the subgrade can be settled by consolidation of original ground, compression due to self weight, plastic displacement due to train operation, and unequal settlement due to embankment material or improper compaction, therefore many efforts have been given for sufficient compaction and use of proper filling materials in the construction stage. The purpose of this study is to investigate the deformation state of subgrade in the Gyeongbu high speed railway. The investigation on the subgrade settlement was performed by choosing representative sections suspected to be settled based on the previous GPR test results and track maintenance history, measuring the settlement for some time period after installing settlement measuring instruments on and under the reinforced road bed. and analyzing the long-term subgrade settlement data from monitoring system which was installed at the construction stage of the high speed railway.

• Nuclear Engineering and Technology
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• v.46 no.2
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• pp.125-146
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• 2014

This review aims to provide a synthesis of the knowledge generated and the lessons learned in roughly 15 years of UMo dispersion fuel R&D in Europe through a series of irradiation experiments. A lot of irradiations were also performed outside of Europe, particularly in the USA, Russia, Canada, Korea and Argentina. In addition, a large number of out-of-pile investigations were done throughout the world, providing support to the understanding of the phenomena governing the UMo behaviour in pile. However, the focus of this article will be on the irradiations and Post-Irradiation Examination (PIE) results obtained in European experiments. The introduction of the article provides a historic overview of the evolution and progress in the high density UMo dispersion fuel development. The ensuing sections then provide further details on the various phases of the development, from the UMo dispersion in a pure Al matrix through the addition of Si to the matrix to address the interaction layer formation and finally to the more advanced solutions to the excessive swelling encountered in various experiments. This review was based only on published results or results that are currently in the process of being published.

• Ocean and Polar Research
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• v.32 no.3
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• pp.267-268
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• 2010

Many countries has been interested in studying the East Sea to look ahead into the world oceans' future, since the East Sea has been known as a miniature ocean. In this respect, PICES decided the East Asian Seas Time-series (EAST) studies, and the East Sea as the first subject (EAST-I). Since 2006 Ministry of Land, Transport & Maritime Affairs, Korea has supported the Korean EAST-I program. Through the Korean EAST-I program, 44 research papers were published in various scientific journals. This special issue contains 6 research articles including results from the interdisciplinary observation in the summer, 2008. Those articles cover the entire East Sea from the Korea Strait to the Japan Basin, and also cover the studies of the euphotic layer to the bottom sediment. MLTM and KIMST have provided full support to EAST-I program. KHOA carried out the joint cruises in the Ulleung Basin. Those are deeply appreciated. Finally, we would like to express our gratitude to the editorial board of Ocean & Polar Research.

• The Journal of the Korea Contents Association
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• v.6 no.11
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• pp.126-134
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• 2006

The object oriented co-modeling methodology, previously introduced, employs a layered approach in war game models development in which an upper layer models abstract behavior of an object and a lower one models details of the object. Within the methodology military domain experts and simulation experts models an object at the upper and the lower layers, respectively in concurrent manner. This paper proposes a method of constructing a war game simulator using parametric behavior modeling technique, which provides a means for military domain experts/users to change model's detailed behavior with no knowledge on modeling semantics. The proposed simulator would support new algorithms or strategies with minimal cost and could be modified even by the users who are ignorant about modeling technique. To demonstrate the effectiveness of the proposed framework, a naval war game simulator is exemplified.