• Title/Summary/Keyword: Mobile Computing

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Design and Prototyping of Partial Connection Manager for Mobile Computing Service (이동 컴퓨팅 서비스를 위한 부분 연결 관리자의 설계 및 프로토타입핑)

  • Kim, Pyeong-Jung;Yun, Seok-Hwan;Jin, Seong-Il
    • The Transactions of the Korea Information Processing Society
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    • v.7 no.6
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    • pp.1932-1940
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    • 2000
  • We must solve problems caused by mobile computing environments for supporting efficient mobile computing services. The problem is the use of wireless medium having high error rates and low bandwidth, and the sudden network disconnection to reduce the power consumption of a mobile host and the cost of the network connection. For these problems, we proposed the architecture of the partial connection manager and designed and implemented that in this paper. In particular, The partial connection manager creates the limited number of mobile agents according to priority and sends them in parallel to server systems and combines results of them process rapidly the user request. By applying the proposed partial connection manager to the mobile computing services called cybermarket, we knew that the mobile agent technique could be suited to the mobile computing environment and overcome the partial connection problem caused by eh mobile computing environment.

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An Efficient Mutual Exclusion Protocol in a Mobile Computing Environment

  • Park, Sung-Hoon
    • International Journal of Contents
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    • v.2 no.4
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    • pp.25-30
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    • 2006
  • The mutual exclusion (MX) paradigm can be used as a building block in many practical problems such as group communication, atomic commitment and replicated data management where the exclusive use of an object might be useful. The problem has been widely studied in the research community since one reason for this wide interest is that many distributed protocols need a mutual exclusion protocol. However, despite its usefulness, to our knowledge there is no work that has been devoted to this problem in a mobile computing environment. In this paper, we describe a solution to the mutual exclusion problem from mobile computing systems. This solution is based on the token-based mutual exclusion algorithm.

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ITS 서비스 : Killer Application of Mobile Computing

  • 오종택;박철희
    • Korea Information Processing Society Review
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    • v.5 no.3
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    • pp.49-55
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    • 1998
  • 현재까지는 무선통신망을 통해 음성 전화 서비스가 주류를 이루고 있지만 향후에는 무선망과 컴퓨터를 결합한 신규 무선 멀티미디어 서비스의 수요가 폭발적으로 증가할 것이다 본 논문에서는 그 주요 서비스를 제공할 Mobile Computing System(MCS)를 개략적으로 설명하고 Mobile Computing의 선도적인 응용으로써 주목받고 있는 ITS서비스와 소요 기술에 대해서 기술한다.

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A Study for agent-based Integration Framework in mobile environment (모바일 환경에서 에이전트를 이용한 설계자원의 통합)

  • 옥형석;이수홍
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • pp.193-196
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    • 1997
  • A mobile computing environment has many difference in character from conventional communication over wired network. These include very presents distributed design system based the mobile agent for mobile computing environment. To integrate design resource, we presented ISA(Integration Service Agent, which allows a designer to build integrated application using distributed resources, and to collaborative by exchanging service. Also we propose ICM(XML based Intelligent Connection Manger) using mobile agent. And suggested new intelligent data and process transfer architecture using ICM to implement an agent based design system in mobile environment.

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Mobile Computing Algorithm on IEEE 802.11b for Ubiquitous Computing

  • Kim, Wu-Woan
    • Journal of the Korean Data and Information Science Society
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    • v.19 no.1
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    • pp.11-24
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    • 2008
  • In this paper, the patterns of movement used in the mobile communication systems are adopted in the mobile computing environment to reduce handover delay and to support seamless handover for MIPv6 based on IEEE 802.11 networks. That is, RtSolPr message and PrRtAdv message can be treated before handover. As the result, it is possible to assign NCoA to MN and Next Access Router(NAR) before handover starts. This can minimize handover delay and reduce the total handover delay.

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Recovery Model Improvement using BISLD in Mobile Computing Environment (모바일 컴퓨팅 환경에서 BISLD를 이용한 회복모델 개선)

  • Cho, Sung-Je;Han, Seong-Soo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.10
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    • pp.4786-4793
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    • 2012
  • In a recent mobile computing environment, the research for a transaction model have been actively carried out to deal with real-time transaction. However, the research for recovery model is relatively insufficient. Therefore, it would be very important for mobile recovery methods for database stability, just in case of data loss due to hand-off in mobile computing system. So, further efficient research should be keenly done to reduce I/O hand-off in mobile computing systems. SLL method increases I/O time due to sequential file. This paper have been suggested to efficient mobile recovery method in mobile computing system. Finally, it has been clearly demonstrated for system efficiency, conducting the performance assessment that currently proposed recovery system.

Concurrency Control for Transaction Management in Mobile Computing (모바일 계산환경에서 거래 관리를 위한 동시성 제어)

  • Rhee, Hae-kyung
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.40 no.6
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    • pp.22-31
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    • 2003
  • Traditional concurrency control strategies for database system are inappropriate for mobile computing environments in which communication disconnection could occur frequently. The time available to access transactions may be extremely limited in mobile computing. In order to ensure that this time is utilized most effectively, the short-lived transactions must be a main stream of transactions. Service handoffs which occur due to communication disconnection, could degrade the performance of mobile transactions especially for short-lived transactions. Altruistic locking protocol is in its nature favorable to short-lived transactions since it applies the donation of locks to long-lived transactions as early as possible. Performance for short-lived transactions could be improved when we applied altruistic locking to mobile computing.

Analysis of Optimistic Cache Protocols based on broadcasting for Mobile Computing Environments (이동 컴퓨팅 환경에서 방송기반의 낙관적 캐쉬 프로토콜들에 대한 분석)

  • Cho, Sung-Ho
    • Journal of Internet Computing and Services
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    • v.6 no.5
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    • pp.177-185
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    • 2005
  • Caching in mobile computing environments Is an important technique that will reduce the effects such as limitation of bandwidth, restriction of resources and frequent disconnection. To reduce limitation and disconnection problems in mobile computing, a new form of caching system have been proposed based on a broadcast approach. This paper proposes a broadcast based cache protocol and examines the behaviors of the proposed scheme and well known schemes such as multiversion based scheme and Certification Reports. By a detailed simulation, we show some characteristics of different approaches to detect and resolve conflicts. We also show proposed scheme out performs other schemes with a low space and operation overhead.

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Modified GOMS-Model for Mobile Computing (모바일 작업을 위한 수정된 GOMS-model에 대한 연구)

  • Lee, Suk-Jae;Myung, Ro-Hae
    • Journal of the Society of Korea Industrial and Systems Engineering
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    • v.32 no.2
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    • pp.85-93
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    • 2009
  • GOMS model is a cognitive modeling method of human performance based on Goal, Operators, Methods, Selection rules. GOMS model was originally designed for desktop environment so that it is difficult for GOMS model to be implemented into the mobile environment. In addition, GOMS model would be inaccurate because the original GOMS model was based on serial processing, excluding one of most important human information processing characteristics, parallel processing. Therefore this study was designed to propose a modified GOMS model including mobile computing and parallel processing. In order to encompass mobile environment, an operator of 'look for' was divided into 'visual move to' and 'recognize' whereas 'point to' and 'click' were combined into 'tab.' The results showed that newly introduced operators were necessary to estimate more accurate mobile computing behaviors. In conclusion, modified-GOMS model could predict human performance more accurately than the original GOMS model in the mobile computing environment.

A Dynamic Packet Recovery Mechanism for Realtime Service in Mobile Computing Environments

  • Park, Kwang-Roh;Oh, Yeun-Joo;Lim, Kyung-Shik;Cho, Kyoung-Rok
    • ETRI Journal
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    • v.25 no.5
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    • pp.356-368
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    • 2003
  • This paper analyzes the characteristics of packet losses in mobile computing environments based on the Gilbert model and then describes a mechanism that can recover the lost audio packets using redundant data. Using information periodically reported by a receiver, the sender dynamically adjusts the amount and offset values of redundant data with the constraint of minimizing the bandwidth consumption of wireless links. Since mobile computing environments can be often characterized by frequent and consecutive packet losses, loss recovery mechanism need to deal efficiently with both random and consecutive packet losses. To achieve this, the suggested mechanism uses relatively large, discontinuous exponential offset values. That gives the same effect as using both the sequential and interleaving redundant information. To verify the effectiveness of the mechanism, we extended and implemented RTP/RTCP and applications. The experimental results show that our mechanism, with an exponential offset, achieves a remarkably low complete packet loss rate and adapts dynamically to the fluctuation of the packet loss pattern in mobile computing environments.

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