• Journal of KIISE:Information Networking
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• v.30 no.2
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• pp.143-154
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• 2003

There is a growing trend in developing system for distributed mobile system that supports services - job flow management, video conference, replicated data management and resource allocation. Supporting these services, applications have to use causally ordered message delivery. Previous proposals that provide causally ordered message delivery have problems such as communication overhead, message delaying, scalability, computing overload of mobile host. In this paper, we proposed efficient protocol for causally ordered message delivery using the methods that MSS maintains dependency information matrix between MSS and MH, Piggybacking dependency information about each immediate predecessor message. Proposed algorithm, when compared with previous proposals, provides a low message overhead, and low probability of unnecessary inhibition in delivering messages. Also, it consider resource restriction of MH and low bandwidth of wireless communication by computing most of algorithm at MSS, and reduce processing delay by executing causally ordered message delivery a unit of MH.

• Journal of Communications and Networks
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• v.6 no.2
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• pp.147-155
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• 2004

In this paper, we propose an efficient sequencing technique, namely minimum Row time scheduling (MFTS), to manage variable-Iength message transmissions for single-hop passive starcoupled WDM optical networks. By considering not only the message length but also the state of the receivers and the tuning latency, the proposed protocol can reduce the average delay of the network greatly. This paper also introduces a new channel assignment technique latency minimizing scheduling (LMS), which aims to reduce the scheduling latency. We evaluate the proposed algorithm, using extensive discrete-event simulations, by comparing its performance with shortest job first (SJF) algorithm. We find that significant improvement in average delay could be achieved by MFTS algorithm. By combining the proposed message sequencing technique with the channel selection technique, the performance of the optical network could be further improved.

• The Journal of the Korea Contents Association
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• v.9 no.3
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• pp.49-57
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• 2009

This paper has proposed Flow Holding Time based Link State Update(LSU) Algorithm that can improve the performance of the existing LSU algorithms. As the existing LSU algorithms are based on the network traffic information, the proposed algorithm is based on flow holding time so we can minimize the LSU message overhead and has not had a strong influence on the depreciation of QoS routing performance. We apply a flow holding time in order to decrease the number of LSU message. We have evaluated the performance of the proposed model and the existing algorithms on MCI simulation network using the performance metric as the QoS routing blocking rate and the mean update rate per link, it thus appears that we have verified the performance of this algorithm.

• Journal of the Korea Society of Computer and Information
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• v.14 no.5
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• pp.133-139
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• 2009

This paper has proposed Flow Holding Time based Link State Update(LSU) Algorithm that has minimized the LSU message overhead in QoS routing and has not had a strong influence on the depreciation of QoS routing performance. We apply a flow holding time in order to decrease the number of LSU message. We have evaluated the performance of the proposed model and the existing algorithms on MCI simulation network using the performance metric as the QoS routing blocking rate and the mean update rate per link, it thus appears that we have verified the performance of this algorithm.

• Transactions of The Korea Fluid Power Systems Society
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• v.8 no.4
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• pp.17-23
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• 2011

Proportional control solenoid is a type of modulating valve that can continuously control the valve position with magnetic force of solenoid. Recent microcontroller based digital servocontroller for proportional valve is being developed toward the smart valve with additional features such as enhanced control algorithm for finer process and intelligent on-board diagnosis for maintenance. In this paper, development of servocontroller network control with CAN bus which is free from problems of security and network traffic jam is presented. Design of network control system includes modes of communication between master and slave, assignment of 29bit message identifier and message objects, transaction of communication sequence, etc. Monitoring function and control experiments for remote valve through CAN network prove the extended function of smart valve control system.

• International Journal of Contents
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• v.15 no.3
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• pp.21-31
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• 2019

This study employs an experimental design to investigate the conditions under which the use of AR may be particularly effective or rather ineffective in advertising contexts. We first discuss the inconsistent results regarding the effectiveness of AR on advertising message comprehension and argue that these inconsistencies can be at least partly explained by the moderating effect of an individual's resistance to innovation (i.e., AR technologies). We then provide statistically significant interaction effects between ad types (AR-based, traditional 2D) and innovation resistance. Finally, we suggest that the effect of AR on certain variables is constrained or unconstrained by an individual's level of receptivity or resistance to a new technology-based advertising platform, and that flow experience is equivalent regardless of these levels.

• Journal of KIISE:Computing Practices and Letters
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• v.14 no.6
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• pp.609-613
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• 2008

In Large scale system, components are developed by many different developers. In such a development environment, efficiency of the development depends largely on effectiveness of interface management. In the early stage of development, many components are newly defined or modified quite often. These definitions and modifications of components cause the change of interfaces between components. If changes of interfaces are not properly managed, many developers may implement components based on different version of interfaces. This causes decrease in efficiency of development. "Message Definition and Management system (MDMS)" provides the means to cope with the inefficiency of unmanaged interface definitions and changes. MDMS automatically generates source code and Interface Design Description (IDD). The automatic generation of source code and IDD prevents the disagreement between code and documents. Furthermore, MDMS shows the overall view of message flow for a system. Based on this information, we can optimize the system identifying message bottleneck and apply to support for the performance tuning of the system.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.6 no.3
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• pp.41-49
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• 2016

In this paper, an IoT system which is increasingly popular in these days is developed. Among various international standards on the area, one M2M communication protocol is used in the system. The 0neM2M-based IoT system consists of ADN-AE modules and CSE modules. The ADN-AE module provides applications of various services. It also monitors a CSE module. The CES module is a platform that provides common services which should be provided to various AEs in an IoT system. The CSE module consists of a Network Manager module, a Message Handler module, and a Resource Manager module. The Network Manager module controls oneM2M communication and data flow in the system. The Message Handler module processes transmitted messages and the Resource Manager module manages the Resource Tree. The resource tree stores information of the objects to be managed in the system. Also, internal data flow and protocol mapping in the modules are explained.

• The Transactions of the Korea Information Processing Society
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• v.7 no.6
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• pp.1874-1885
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• 2000

When a receiver of ciphertext message can not decrypt a message because he has lost his private-key, the private-key of receiver and session-key of the message should be recovered. In this paper, we developed an Encapsulation based Key Recovery System (EKRS). EKRS is a new key encapsulation based key recovery system which is characterized by secretly choice of KRA, randomized target keys. n-way recovery type, and useful for commercial key recovery. EKRS is formally specified by a pictorial model, an Extended Cryptographic Timed Petri Net (ECTPN). Secure information flow and reachability of a session-key are verified by using reachability graph of ECTPN. EKRS, executing over a Public Key Infrastructure, can be used as a security solution in Web based applications such as CALS, EC an EDI.

• Journal of KIISE:Software and Applications
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• v.29 no.9
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• pp.605-618
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• 2002

The CBD (Component Based Development) is a requisite technique for the Time-To-Market, and a highly reusable component should be provided to develop a variety of domain applications with the use of components. To increase the reusability of components, they should be developed by analyzing requirements of many different kinds of domains. However, to analyze requirements of a variety of domains related to the components to be developed and to include them inside the components will give burden to developers. Also, providing only general components that have common facilities for the several domains is not easy to accomplish the time-to-market since there are other domains that the developers have to develop. As such, developing common component through the analysis of several domains at the time of the CD (Component Development) does not always guarantee high reusability of the component, but gives burden to developers to develop another development since such components have common functions. Considering this, this paper proposes the component customization technique to reuse common components as well as special components. The reusability of the component can be increased by providing changeability of the attribute, behavior and message flow of the component. This customization technique can change the message flow to integrate developed components or to provide new functions within the component. Also, provides a technique to replace the class existing within the component with other class or to exchange the integrated component with the component having a different function so that requirements from a variety of domains may be satisfied. As such, this technique can accept the requirements of several domains. As such, this customization technique is not only the component with a common function, but it also secures reusability components in the special domain.