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pISSN : 1598-849X / eISSN : 2383-9945

2020 KCI Impact Factor : 0.4
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2010, Vol.15, No.3

  • 1.

    Dynamic Voltage and Frequency Scaling based on Buffer Memory Access Information

    Kwak, Jong Wook | 김주환 | 2010, 15(3) | pp.1~10 | number of Cited : 1
    Abstract PDF
    As processor platforms are continuously moving toward wireless mobile systems, embedded mobile processors are expected to perform more and more powerful, and therefore the development of an efficient power management algorithm for these battery-operated mobile and handheld systems has become a critical challenge. It is well known that a memory system is a main performance limiter in the processor point of view. Although many DVFS studies have been considered for the efficient utilization of limited battery resources, recent works do not explicitly show the interaction between the processor and the memory. In this research, to properly reflect short/long-term memory access patterns of the embedded workloads in wireless mobile processors, we propose a memory buffer utilization as a new index of DVFS level prediction. The simulation results show that our solution provides 5.86% energy saving compared to the existing DVFS policy in case of memory intensive applications, and it provides 3.60% energy saving on average.
  • 2.

    A study for measurement of radial artery oxygen saturation system using photoelectric plenthysmography

    KIM Kyungho | 2010, 15(3) | pp.11~18 | number of Cited : 1
    Abstract PDF
    In this study, the pulse of radial artery and oxygen saturation are detected using photoelectric plethysmograph method. Using our device designed reflection type, we can detect the reflected light by radial artery and by switching circuit, we can also separate to 625nm band signal and 940nm band signals. The separated signals are converted as a pulse data by the pulse signal processing circuit. In this study, the reflection type of oxygen saturation calculation method is applied instead of the transmission type because of the reflection type sensor is used to measure the radial artery. As a result, we can detect about 97% accuracy of the oxygen saturation compare with the conventional method. For the accurate signals, the wrist band with sensor was designed and fixed on the radial artery. As a result, this wrist band type sensor was applicable to prevent position errors from motion artifact and could increase the accuracy during the measuring.
  • 3.

    Design and Implementation of Mobile RFID Middleware based Pet Management System

    ParkByoungSeob | 2010, 15(3) | pp.19~26 | number of Cited : 0
    Abstract PDF
    The most critical element in the real-time operation of RFID application programs that are suitable for the mobile environment is the RFID middleware, made exclusively for mobile handsets, which processes collected data on a real-time basis and sends only the useful information to the application client. In this paper, we intend to design and implement the Pet management system for optimized mobile RFID middleware that supports real-time data processing. The proposed Pet management system consists of registration module, retrieval module, communication module, and display module in order to display retrieval result from server. Also, the captured data in the PDA is transmitted to the server and another client system using the mobile application interface that supports the SOAP application access protocol.
  • 4.

    Performance Comparison of Skin Color Detection Algorithms by the Changes of Backgrounds

    Jang Seok-Woo | 2010, 15(3) | pp.27~35 | number of Cited : 0
    Abstract PDF
    Accurately extracting skin color regions is very important in various areas such as face recognition and tracking, facial expression recognition, adult image identification, health-care, and so forth. In this paper, we evaluate the performances of several skin color detection algorithms in indoor environments by changing the distance between the camera and the object as well as the background colors of the object. The distance is from 60cm to 120cm and the background colors are white, black, orange, pink, and yellow, respectively. The algorithms that we use for the performance evaluation are Peer algorithm, NNYUV, NNHSV, LutYUV, and Kimset algorithm. The experimental results show that NNHSV, NNYUV and LutYUV algorithm are stable, but the other algorithms are somewhat sensitive to the changes of backgrounds. As a result, we expect that the comparative experimental results of this paper will be used very effectively when developing a new skin color extraction algorithm which are very robust to dynamic real environments.
  • 5.

    A Design of Multi format HD LCD Monitor for Broadcasting

    Han, Sung-il | 전응섭 | 노형일 | 2010, 15(3) | pp.37~43 | number of Cited : 0
    Abstract PDF
    In this study, the multi format 8.4" LCD monitor for broadcasting has been proposed by the simple circuit design and the efficient processing technique. The small sizing technique, the mixed-type video signal processing technique, the emerging skill of multi-format HD signal to one port, the dividing technique between the analog and digital signal, the embedded audio signal developing technique are the key researches of this study. The proposed multi format 8.4" LCD monitor has been focused on the broadcasting field and has been supposed to have the efficiency at that field.
  • 6.

    A Study about Cross-Cultural Content Analysis on Global Website in Korea, US, Japan, China

    오정민 | Nammee Moon | 2010, 15(3) | pp.45~53 | number of Cited : 3
    Abstract PDF
    When the user's role is getting more important in contents communicated online, we must know that the cultural trait of content that is reflecting user's mental model, needs and tastes. An attempt to study about cross-cultural characteristics focused on contents of global website give us the best chance to understand user. This paper takes a look if there are any linkages between certain country and its preferable contents and analyze that whether this preference is result from the cultural differences or not. This analysis is based on Hofstede's and Schwartz's framework. So, this content analysis examines cultural influence on the contents of global website in Korea and U.S and Japan and China. The results provide CIC(Cultural Index of Content) which is extended framework adding interaction. We expect that it can help service providers and content creators to have some new ideas.
  • 7.

    A Handoff Improvement Method for AP Choose Guarantee Network Performance of Mobile Node in Wireless LAN Systems.

    김동근 | KimSangBok | 2010, 15(3) | pp.55~63 | number of Cited : 0
    Abstract PDF
    On Handoff, existing AP search has chosen one of various APs according to signal strength. However IEEE 802.11 uses Medium Access method with CSMA/CA(Carrier Sensing Multiple Access /Collision Avoidance) that competes to obtain a channel by sharing common medium. For that reason, network performance is heavily affected by the number of nodes and network congestion aside from signal strength. Consequently, in this paper we propose the method that choose one AP which ensures more improved network performance and set up a link, reflecting AP network information in Handoff area, on Handoff in the process of AP selection. We also demonstrate through simulation that it gets maximum performance even in the wireless network which many users concurrently access to, and it has considerable effects on aspects of resources and network management by distribution of users.
  • 8.

    Improvement of Received Optical Power Sensitivity in Asymmetric 2.5Gbps/1.2Gbps Passive Optical Network with Inverse Return to Zero(RZ) coded Downstream and NRZ upstream re-modulation

    PARK SANGJO | 2010, 15(3) | pp.65~72 | number of Cited : 3
    Abstract PDF
    We propose the asymmetric 2.5Gbps/622Mbps PON(Passive Optical Network) in order to reduce the bandwith of filter at receiver with inverse RZ(Return to Zero) code coded downstream and NRZ(Non Return to Zero) upstream re-modulation. I theoretically analyze BER(Bit Error Rate) performance and the power sensitivity with the optimal threshold level by performing simulation with MATLAB according to the types of downstream data. The results have shown that the optimal threshold level at the optical receiver could be saturated at 0.33 as the optical received power increase more than -26dBm to keep of BER to a minimum. Also the power sensitivity is more improved by about 3dB by fixing the threshold level at 0.33 than the conventional receiver. The proposed system can be a useful technology for optical access networks with asymmetric upstream and downstream data rates because the optical receiver can be used without controlling threshold levels and that does not require a light source in optical network unit (ONU) and its control circuits in the optical line termination (OLT).
  • 9.

    An Efficient Algorithm for Finding the Earliest Available Interval on Connection-Oriented Networks

    Kyun Rak Chong | 2010, 15(3) | pp.73~80 | number of Cited : 1
    Abstract PDF
    The advancement of communication and networking technologies has enabled e-science and commercial application that often require the transport of large volume of data over wide-area network. Schedulable high-bandwidth low-latency connectivity is required to transport the large volume of data. But the public Internet does not provide predictable service performance. Especially, if data providers and users are far away, dedicated bandwidth channels are needed to support remote process efficiently. Currently several network research projects are in progress to develop dedicated connectionsy sA bandwidth scheduler computes an user requested path based on network topology information and link bandwidth allocationsy In this paper, we have proposed an efficient algorithm for finding the earliest time interval when minimum bandwidth and duration are giveny Our algorithm is experimentally compared with the known algorithm.
  • 10.

    An Efficient Peer-to-Peer Streaming Scheme Based on a Push-Mesh Structure

    김진성 | 김동일 | 김은삼 and 1other persons | 2010, 15(3) | pp.81~89 | number of Cited : 5
    Abstract PDF
    The research on peer-to-peer streaming schemes has largely focused on tree-push and mesh-pull structures. However, the tree-push structure has a defect that the tree restructuring time is long, and the mesh-pull structure has long startup delay and lag time from source servers. In this paper, we propose a new peer-to-peer live streaming scheme based on a push-mesh structure that takes advantages of tree-push and mesh-pull structure simultaneously. This structure basically provides the mesh-pull mechanism for data transmission and utilizes peers with high network upload capacity. It also supports the push mechanism along with paths from a source server, super peers, and selected general peers. By NS-2 simulation experiments, we finally show that our proposed scheme can achieve shorter startup delay than the mesh-pull structure, similar lag time to tree-push structure and best playback continuity among the three schemes.
  • 11.

    Security Improvements on the Remote User Authentication Scheme Using Smart Cards

    Seo Jeong-Man | Younghwa An | 2010, 15(3) | pp.91~97 | number of Cited : 3
    Abstract PDF
    Recently Hu-Niu-Yang proposed the user authentication scheme to improve Liu et al's scheme. But the Hu-Niu-Yang's scheme has not been satisfied security requirements considering in the user authentication scheme using the password based smart card. In this paper, we proved that Hu-Niu-Yang's scheme is vulnerable to the off-line password guessing attack in case that the attacker steals the user's smart card and extracts the information in the smart card. Also, the improved user authentication scheme solving the security vulnerability was introduced, thus preventing the attacks, such as password guessing attack, forgery attack impersonation attack, and replay attack. For preventing those attacks, the our proposed scheme need more hash functions and exclusive-OR operations than Hu-Niu-Yang's scheme.
  • 12.

    Development of Integrated Operating System for Transportation Card Unmanned sales/charging machines

    김형환 | Shin Dong Suk | 2010, 15(3) | pp.99~109 | number of Cited : 0
    Abstract PDF
    Since introduced in 1997, the transportation card system in Korea has been developed up to the world-top-tier technical level and gradually implemented in many other countries. Especially, the public transportations are significantly considered in terms of reducing greenhouse gas emission and environment pollution. In addition, a nation-wide transportation card system will be feasibly completed until 2013. However, for overcoming user’s inconvenience, the unmanned sales/charging machines of the cards should be urgently required. In this paper, a new integrated operating system for unmanned sales/charging machines of such cards is designed and implemented by analyzing problems of the existing machines. The proposed system is hierarchically composed of multiple modules; machine initialization, work finishing, sales, charging, A/S handling, and management modules. We established and operated this machine in Seoul and Gyeonggi region. This research demonstrates that spread of the user-friendly integrated operating system improve user’s convenience especially with respect to interoperability among transportation means and their areas.
  • 13.

    A Study on artificial lighting source using X3D

    박경배 | 강경인 | 2010, 15(3) | pp.111~119 | number of Cited : 0
    Abstract PDF
    An artificial light source has a character that a light emits from a point to all directions with many radial and straight ray shapes. It is very difficult and complex to render those emitting lights. Also, users have difficulty in expressing exactly 3D objects because of colors varying with changing of a light and having many parameters. In this paper, to solve those problems we design an artificial light source using X3D to create a model that represents easily many radial and straight ray shapes and propose the online system that each factors of colors to be reflected by a light is separated and then users can control them to detect object's colors by a mouse. Various light sources with reality can be easily created using proposed system.
  • 14.

    Development of e-CRM System Using LBS of Cellular Phone and Call Back URL SMS

    전진호 | 서필교 | 2010, 15(3) | pp.121~128 | number of Cited : 1
    Abstract PDF
    Whenever and wherever, recognizing location of object such as human as well as things, ubiquitous Location-Based Service which provides useful service based on this are rising as an important service. In this paper, we implemented customized real time 1:1 e-CRM system that can communicate with user's mobile phone through using Location-Based Service of mobile phone. Among various scenarios that are applicable to designed system, development and test were conducted based on scenario that provides shopping information and discount information to customers through SMS as they approach to vicinity of large discount store and allow them to download discount coupons through Call Back. The suggested system will be applied to various service event and can be used as a customized real time marketing method according to user's personal activity area.