• The Transactions of the Korea Information Processing Society
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• v.6 no.11S
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• pp.3379-3389
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• 1999

Important network application services have been rapidly increased along with the growth of the Internet. So, it is desirable for such applications to serve transparently, continuously and safely even if the network is temporally disconnected or certain hosts running those services are crashed down. To satisfy such requirementes, many group communication systems have been developed; but, those systems restrict its range within a single LAN or directly interconnected LAN environments since the communication through the Internet is too slow and too unreliable to support group communication. As of now, it is expected the Internet is going to e sufficiently fast and reliable in the near communication system, named FACE(Java Advanced Communication Environment), supporting Extended Virtual which is a basic communication layer, RPGS(Reliable Process Group Service) which manages application process groups, and JACE API for developing Java application services and clients programs. In addition, an experimental replicated object space is developed as an application of the JACE system.

• ETRI Journal
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• v.29 no.6
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• pp.745-754
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• 2007

In this paper, we present the Enhanced Communication Transport Protocol-Part 5 (ECTP-5), which provides scalable and reliable multicast communication service for many-to-many applications by constructing high quality recovery trees from two-layer logical trees and repairing the losses via unicast automatic repeat request-based error control. In order to realize the protocol, we developed feasible protocol architectures and building blocks including additional functions which deal with engineering details, such as membership dynamics and sender coordination. Experimental results show that ECTP-5 scales well with various session sizes and packet loss rates in terms of control overhead and recovery latency.

• Transactions on Control, Automation and Systems Engineering
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• v.1 no.2
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• pp.121-127
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• 1999

In this paper, we present robust reliable H$\infty$ controller design methods of continuous and discrete uncertain time delay systems using LMI (linear matrix inequality) technique, respectively. Also the existence conditions of state feedback control are proposed . Using some changes of variables and Schur complements, the obtained sufficient conditions are transformed into an LMI form. The closed loop system by the obtained controller is quadratically stable with H$\infty$ norm bound for all admissible uncertainties, time delay, and all actuator failures occurred within the prespecified set. We show the validity of the proposed method through numerical example.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2004.04a
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• pp.349-352
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• 2004

In this literature, the selection of data set among the universe set is carried out with the fuzzy entropy function. By the definition of fuzzy entropy, we have proposed the fuzzy entropy function and the proposed fuzzy entropy function is proved through the definition. The proposed fuzzy entropy function calculate the certainty or uncertainty value of data set, hence we can choose the data set that satisfying certain bound or reference. Therefore the reliable data set can be obtained by the proposed fuzzy entropy function. With the simple example we verify that the proposed fuzzy entropy function select reliable data set.

• Journal of the Korean Institute of Intelligent Systems
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• v.14 no.5
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• pp.655-659
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• 2004

In this literature, the selection of data set among the universe set is carried out with the fuzzy entropy function. By the definition of fuzzy entropy, the fuzzy entropy function is proposed and the proposed fuzzy entropy function is proved through the definition. The proposed fuzzy entropy function calculate the certainty or uncertainty value of data set, hence we can choose the data set that satisfying certain bound or reference. Therefore the reliable data set can be obtained by the proposed fuzzy entropy function. With the simple example we verify that the proposed fuzzy entropy function select reliable data set.

• Journal of information and communication convergence engineering
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• v.10 no.2
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• pp.129-134
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• 2012

As application-specific requirements for wireless sensor networks emerge, both real-time and reliable communications become major research challenges in wireless sensor networks due to the many constraints on nodes and wireless links. To support these services, several protocols have been proposed. However, since most of them were designed as well as developed for general purpose applications, it is not recommended that they be directly adapted to applications with special requirements. In this paper, we propose a way to extend the current reliable transport protocol to cover a special real-time service, the (m,k)-firm deadline stream, in wireless sensor networks. While the proposed scheme is basically built on the PSFQ protocol for reliability, some features have been newly developed to support the (m,k)-firm stream efficiently. Finally, simulation results are given to demonstrate the feasibility of the proposed scheme in high traffic and with failed links.

• Proceedings of the IEEK Conference
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• 2000.11c
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• pp.165-168
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• 2000

Since the IP multicast was proposed, there have been many research works on reliable multicast protocols［1］. In multicast communication, many reliable multicast schemes were studied in order to overcome packet losses in the network. However the fact that packets are lost in the underlying networks but the solutions are sought in the end hosts makes the search for solutions difficult. If routers can identify packets before dropped from congestion, the routers can initiate recovery process. recovery scheme by routers is proposed. This scheme is much faster than by sender-initiated or receiver-initiated recovery and latency is smaller.

• Journal of Ocean Engineering and Technology
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• v.11 no.4
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• pp.40-48
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• 1997

There are many research results as individual uni-axial tension creep test of heat-resisting materials. However, there are very few about the study on the high temperature creep test for the Initial Strain Method, and especially any study on it about the friction welded joints of SUH3 to SUH35. One of the important concerns is a reliable method of evaluating static creep properties. No reliable method seems available at present to evaluate or predict static creep properties. So, the reliable method to evaluate and predict them by the ISM and AE techniques was made.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.6
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• pp.859-864
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• 2012

The computer network plays an important role in modern digital controllers within a safety system of a nuclear power plant. For the reliable and realtime data communication between controllers, this paper proposes a modified high-reliable MVB(multi-function vehicle bus) as a main control network for a safety system of a nuclear power plant. The proposed network supports the state-based communication in order to ensure the deterministic communication latency, and very fast network recovery when the bus master fails compare to the standard MVB. This paper also shows the implementation results using a FPGA-based testbed.

• Journal of The Institute of Information and Telecommunication Facilities Engineering
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• v.8 no.4
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• pp.201-206
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• 2009

The third generation mobile communications system requiring the reliable multimedia data transmission has provided with the reliable voice, data and video services over the variable propagation environment. However the broadband wireless multiple access technologies cause Inter Symbol Interference (ISI) or Multiple Access Interference (MAI) to degrade the performance of W-CDMA (Code Division Multiple Access) system. Constant Modulus Algorithm (CMA) which is frequently used as the adaptive blind equalizers to remove the interfering signal has ill-convergence phenomenon without proper initialization. In this paper, new blind equalization method based on conventional CMA is proposed to improve the channel efficiency, and through computer simulation this is tested over the time varying fading environment of mobile communication system. Consequently, new blind equalization method into concatenated Kalman filter with CMA is verified better than conventional CMA through adopting minimum mean square errors and eye-pattern obtained from algorithm are compared.