• Journal of applied mathematics & informatics
• /
• v.29 no.1_2
• /
• pp.211-225
• /
• 2011

In this paper, a class of bi-directional associative memory (BAM) fuzzy cellular neural networks with distributed delays and impulses is formulated and investigated. By employing an integro-differential inequality with impulsive initial conditions and the topological degree theory, some sufficient conditions ensuring the existence and global exponential stability of equilibrium point for impulsive BAM fuzzy cellular neural networks with distributed delays are obtained. In particular, the estimate of the exponential convergence rate is also provided, which depends on the delay kernel functions and system parameters. It is believed that these results are significant and useful for the design and applications of BAM fuzzy cellular neural networks. An example is given to show the effectiveness of the results obtained here.

• ETRI Journal
• /
• v.30 no.4
• /
• pp.618-620
• /
• 2008

A distributed virtual environment (DVE) allows multiple geographically distributed objects to interact concurrently in a shared virtual space. Most DVE applications use a non-replicated server architecture, which dynamically partitions a virtual space. An important issue in this system is effective scalability as the number of users increases. However, it is hard to provide suitable load balancing because of the unpredictable movements of users and hot-spot locations. Therefore, we propose a mechanism for sharing roles and separating service regions. The proposed mechanism reduces unnecessary partitions of short duration and supports efficient load balancing.

• Proceedings of the Korea Society for Simulation Conference
• /
• 2005.11a
• /
• pp.65-70
• /
• 2005

Recently, Grid is embossed as a new issue according to the need of cooperation related to distributed resources, data sharing, Interaction and so on. It focuses on sharing of large scale resources, high-performance, applications of new paradigms, which improved more than established distributed computing. Because of the environmental specificity distributed geographically and dynamic, the most important problem in grid environment is to share and to allocate distributed grid resources. This paper proposes supply-driven strategies model that is applicable for resource management in grid environment and presents a optimal resource allocation algorithm based on resource demands. Supply-driven strategies model can offer efficient resource management by transaction allocation based on user demand and provider strategy. This paper implements the supply-driven strategies model on the DEVS modeling and simulation environment and shows the efficiency and excellency of this model by comparing with established models.

• Journal of the Korea Society for Simulation
• /
• v.7 no.2
• /
• pp.79-90
• /
• 1998

This paper introduces the concept of web-based simulation and suggests the structure of web-based simulation which reduces the simulation run time and performs simulations in efficient way under distributed environments. Since its introducing in 1996, web-based simulation has been studied only with a tool of applet, but in this paper a method of server applications for client applets will be used. In server application, server transfers objects requested by clients such as simulation engines, reports, files. After each client connects to web-server, and then server allocates simulation modules to connected clients. These work magnify the transferring applets from server and simulation models which were made by clients. This paper also processes a structure for managing efficiently web-based simulation under distributed environment and steps in which clients connect, model, simulate with distributed structure, and programs of proposed structure.

• Journal of Integrative Natural Science
• /
• v.5 no.1
• /
• pp.27-31
• /
• 2012

Relationship between reflection resonance and applied current density in Bragg photonic crystal has been investigated. Multiple bit encodes of distributed Bragg reflector features have been prepared by electrochemical etching of crystalline silicon by using various square wave current densities. Optical characterization of multi-encoding of distributed Bragg reflectors on porous silicon was achieved by Ocean optics 2000 spectrometer for the search of possible applications of multiple bit encoding of distributed Bragg reflectors such as multiplexed assays and chemical sensors. The morphology and cross-sectional structure of multi-encoded distributed Bragg reflectors was investigated by field emission scanning electron micrograph.

• Journal of Information Processing Systems
• /
• v.15 no.2
• /
• pp.410-421
• /
• 2019

Distributed compressed sensing (DCS) states that we can recover the sparse signals from very few linear measurements. Various studies about DCS have been carried out recently. In many practical applications, there is no prior information except for standard sparsity on signals. The typical example is the sparse signals have block-sparse structures whose non-zero coefficients occurring in clusters, while the cluster pattern is usually unavailable as the prior information. To discuss this issue, a new algorithm, called backtracking-based adaptive orthogonal matching pursuit for block distributed compressed sensing (DCSBBAOMP), is proposed. In contrast to existing block methods which consider the single-channel signal reconstruction, the DCSBBAOMP resorts to the multi-channel signals reconstruction. Moreover, this algorithm is an iterative approach, which consists of forward selection and backward removal stages in each iteration. An advantage of this method is that perfect reconstruction performance can be achieved without prior information on the block-sparsity structure. Numerical experiments are provided to illustrate the desirable performance of the proposed method.

• The Transactions of the Korea Information Processing Society
• /
• v.5 no.5
• /
• pp.1140-1150
• /
• 1998

The objective of this paper is to analyze requirements of distributed applications which use the different type of information and support the cooperative work environment between a group of persons in interactive mode, and to provide useful common services for the development of this kind of applications. For this, Interactive Cooperative Application Service as a horizontal service on the application layer and Session Management Service as a support service on the infrastructure layer were defined and designed using the concepts and rules of the Open Distributed Processing system. Application designers may use these services for building those applications which demand the requirements we have characterized in this paper.

• Journal of the Korean Society of Systems Engineering
• /
• v.2 no.2
• /
• pp.45-50
• /
• 2006

Tilting technology is to tilt the train on the curve in order to minimize centrifugal force to passengers and to improve the speed within the limits of passenger's comfort and safety. According to reports from other countries, there is 15~30% speed improvement compared to the conventional trains. Recently, the advent of World-Wide-Web(WWW) and the explosive popularity of the Internet gave birth to collaborative applications which were enabled by computers and networks as their primary media. The progress of 3D computer graphics enabled collaborative applications with 3D virtual environments or distributed virtual environments. In this paper, we explain our implementation of the Share collaboration engine which is for collaboration applications based on a distributed virtual environment. The Share collaboration engine proposes a new Share network architecture for management of participants, and it provides some synchronization methods for 3D objects in virtual collaboration. TTX_PDM is an experimental application that tries to prevent wastes of human, material and time resources in networked virtual collaboration.

• Proceedings of the IEEK Conference
• /
• summer
• /
• pp.421-426
• /
• 2004

Analyzing adaptive possibilities of agents in multi-agents system, we have discovered new aspects of ambient intelligence in distributed modular systems using intelligent building blocks (I-BLOCKS) [1]. This paper describes early scientific researches related to technical design, applicable experiments and evaluation of adaptive processing and information interaction among I-BLOCKS allowing users to easily develop ambient intelligence applications. The processing technology presented in this paper is embedded inside each DUPLO1 brick by microprocessor as well as selected sensors and actuators in addition. Behaviors of an I-BLOCKS modular structure are defined by the internal processing functionality of each I-Blocks in such structure and communication capacities between I-BLOCKS. Users of the I-BLOCKS system can do 'programming by building' and thereby create specific functionalities of a modular structure of intelligent artefacts without the need to learn and use traditional programming language. From investigating different effects of modem artificial intelligence, I-BLOCKS we have developed might possibly contain potential possibilities for developing applications in ambient intelligence (AmI) environments. To illustrate these possibilities, the paper presents a range of different experimental scenarios in which I-BLOCKS have been used to set-up reconfigurable modular systems. The paper also reports briefly about earlier experiments of I-BLOCKS in different research fields, allowing users to construct AmI applications by a just defined concept of modular artefacts [3].

• Korea Multimedia Society
• /
• v.4 no.2
• /
• pp.24-38
• /
• 2000

No Abstract (See Full-text)