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

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2010, Vol.15, No.8

  • 1.

    Development of the Performance Benchmark Tool for Data Stream Management Systems Combined with DBMS

    Gyoung-Bae Kim | 2010, 15(8) | pp.1~11 | number of Cited : 0
    Abstract PDF
    Many applications of DSMS(Data Stream Management System) require not only to process real-time stream data efficiently but also to provide high quality services such as data mining and data warehouse combining with DBMS(Database Management System) to users. In this paper we execute the performance benchmark of the combined system of DSMS and DBMS that is developed for high quality services. We use the stream data of network monitoring application system and combine the traditional representative DSMSs and DBMSs in a single system for the performance testing. We develop the total performance benchmark tool implementing JAVA language for the our testing. For our performance testing, we combine DSMS such as STREAM and Coral8 and DBMS such MySQL and Oracle10g respectively.
  • 2.

    An Optimization of Hashing Mechanism for the DHP Association Rules Mining Algorithm

    Hyung-Bong Lee , Ki-Hyeon Kwon | 2010, 15(8) | pp.13~21 | number of Cited : 0
    Abstract PDF
    One of the most distinguished features of the DHP association rules mining algorithm is that it counts the support of hash key combinations composed of k items at phase k-1, and uses the counted support for pruning candidate large itemsets to improve performance. At this time, it is desirable for each hash key combination to have a separate count variable, where it is impossible to allocate the variables owing to memory shortage. So, the algorithm uses a direct hashing mechanism in which several hash key combinations conflict and are counted in a same hash bucket. But the direct hashing mechanism is not efficient because the distribution of hash key combinations is unvalanced by the characteristics sourced from the mining process. This paper proposes a mapped perfect hashing function which maps the region of hash key combinations into a continuous integer space for phase 3 and maximizes the efficiency of direct hashing mechanism. The results of a performance test experimented on 42 test data sets shows that the average performance improvement of the proposed hashing mechanism is 7.3% compared to the existing method, and the highest performance improvement is 16.9%. Also, it shows that the proposed method is more efficient in case the length of transactions or large itemsets are long or the number of total items is large.
  • 3.

    Index block mapping for flash memory system

    Jung-Hoon Lee | 2010, 15(8) | pp.23~30 | number of Cited : 0
    Abstract PDF
    Flash memory is non-volatile and can retain data even after system is powered off. Besides, it has many other features such as fast access speed, low power consumption, attractive shock resistance, small size, and light-weight. As its price decreases and capacity increases, the flash memory is expected to be widely used in consumer electronics, embedded systems, and mobile devices. Flash storage systems generally adopt a software layer, called FTL. In this research, we proposed a new FTL mechanism for overcoming the major drawback of conventional block mapping algorithm. In addition to the block mapping table, a index block mapping table with a small size is used to indicate sector location. The proposed indexed block mapping algorithm by adding a small size. By the simulation result, the proposed FTL provides an enhanced speed than a conventional hybrid mapping algorithm by around 45% in average, and the requirement of mapping memory is also reduced by around 12%.
  • 4.

    Lane detection method using Median Filter based Retinex Algorithm in Foggy Image

    김영탁 , Hernsoo Hahn | 2010, 15(8) | pp.31~39 | number of Cited : 3
    Abstract PDF
    The paper proposes the median filter based Retinex algorithm to detect the lanes in a foggy image. Whether an input image is foggy or not is determined by analyzing the histogram in the pre-defined ROI(Region of Interest). If the image is determined as a foggy one, then it is improved by the median filter based Retinex algorithm. By replacing the Gaussian filter by the median filter in the Retinex algorithm, the processing time can be reduced and the lane features can be detected more robustly. Once the enhanced image is acquired, the binarization based on multi-threshold and the labeling operations are applied. Finally, it detects the lane information using the size and direction parameters of the detected lane features. The proposed algorithm has been evaluated by using various foggy images collected on different road conditions to prove that it detects lanes more robustly in most cases than the conventional methods.
  • 5.

    Design and Implementation of Monitoring System for Stable ATSC Mobile DTV

    유샛별 , 손예진 , 조민주 and 2 other persons | 2010, 15(8) | pp.41~49 | number of Cited : 1
    Abstract PDF
    Digital broadcasting system has various affecting factors unlike analog broadcasting system, and has possibility of no signal reception in case of errors due to characteristics of digital system. And, digital broadcasting system has monitoring system for error occurrences handling various factors. ATSC mobile DTV system uses legacy frequency and provides mobile broadcasting services, and also requires monitoring systems for monitoring online broadcasting services and reporting to administrator about interference or influence with legacy systems, and error situations. In this paper, we propose efficient monitoring system which monitors online broadcasting status of ATSC mobile DTV, reports on poor signal reception, video streaming failures to administrator, and maintains reliable digital broad casting system.
  • 6.

    The Recommendation System based on Staged Clustering for Leveled Programming Education

    Kim Kyung-Ah , 문남미 | 2010, 15(8) | pp.51~58 | number of Cited : 3
    Abstract PDF
    Programming education needs learning which is adjusted individual learners' level of their learning abilities. Recommendation system is one way of implementing personalized service. In this research, we propose recommendation method which learning items are recommended for individual learners' learning in web-based programming education environment by. Our proposed system for leveled programming education provides appropriate programming problems for a certain learner in his learning level and learning scope employing collaborative filtering method using learners' profile of their level and correlation profile between learning topics. As a result, it resolves a problem that providing appropriate programming problems in learner's level, and we get a result that improving leaner's programming ability. Furthermore, when we compared our proposed method and original collaborative filtering method, our proposed method provides the ways to solve the scalability which is one of the limitations in recommendation systems by improving recommendation performance and reducing analysis time.
  • 7.

    A Study on Coupling Coefficient and Resonant Frquency tunable Multi-band Internal Antenna

    이문우 , 이상현 | 2010, 15(8) | pp.59~66 | number of Cited : 0
    Abstract PDF
    In this paper, the internal antenna for mobile communication handset which is able to control both coupling coefficient and resonant frequency without any major modification of radiator and ground plane of antenna. Novel internal antenna with its controllable resonant frequency is presented for triple-band or over mobile handsets. The operating range can include GSM(880~960 MHz), GPS(1,575±10 MHz), DCS(1,710~1,880MHz), US-PCS(1,850~1,990 MHz), and W-CDMA(1,920~2,170 MHz). The proposed antenna is realized by combination of a half wavelength loaded line antenna and PIFA(Planner Inverted F Antenna). A single shorting and feeding points are used and they are common to both antenna structures. One of two inductors which is placed at each shorting post, one inductor is for adjusts amount of coupling, and the other controlling the resonant frequency in DCS/US-PCS/WCDMA bands. The inductance range for control of input impedance is between 0nH and 6.8nH, and each of gain variation in GSM, GPS and DCS/US-PCS/WCDMA band is under 0.15dBi, 0.73dBi and 0.29dBi. The inductance range for control of the resonant frequency is between 1640MHz and 2500MHz, and each of gain variation in GSM, GPS and DCS/US-PCS/WCDMA band is under 0.46dBi, 0.53dBi and 0.8dBi.
  • 8.

    A Study on Problem Identification and Diagnosis from Virtual Network

    김정수 | 2010, 15(8) | pp.67~78 | number of Cited : 0
    Abstract PDF
    Various services such as IPTV, VoIP, multimedia over IP, on-line payment, on-line game, etc. were made possible due to the rapid advance of the network. In order to provide secure and seamless services over the network, the Internet service providers are performing continuous network monitoring using NMS. The main function of NMS is to perform a diagnosis to identify the potential causes of failure from event messages. In this paper, a simulation tool, named as NetDoctor, is presented which is capable of identifying and diagnosing the potential problems in the virtual network, before the network model is constructed. In NetDoctor, a series of various and artificial failure is imposed on the virtual network, and it was analyzed if NetDoctor could identify the problems. The experimental results on virtual network show that the developed tool is very effective in identifying and diagnosing the problems. The presented simulation tool can be used in the design of robust network.
  • 9.

    Interrelation Based Resource Allocation Scheme for Mobile Multimedia Networks

    이종찬 , Lee Moonho | 2010, 15(8) | pp.79~87 | number of Cited : 6
    Abstract PDF
    It is widely accepted that the coverage with high user densities in mobile multimedia environments can only be achieved with small cell such as micro- and pico-cell. If handover events occur during the transmission of multimedia, the efficient resource reservation and handover methods are necessary in order to maintain the same QoS of transmitted multimedia traffic because the QoS may be defected by some delay and information loss. In this paper, we propose a resource allocation method in the next generation mobile communication systems, in which the resource allocation process has a tight relation with call admission, call load, and packet scheduling. The simulation results show that our proposed method provides a excellent performance.
  • 10.

    Implementation of HL7 Interface Engine for Medical Information Exchange

    Deuk Young Hwang | 2010, 15(8) | pp.89~98 | number of Cited : 9
    Abstract PDF
    Recently supply of Internet is bringing a important change in medical environments. The hospitals which had a different system is required the system that can efficiently share and exchange medical information. In order to transmission medical information between systems, the Health Level Seven(HL7) interface engine development that can convert medical data to HL7 messages is necessary. The HL7 is a standard protocol for data exchange in healthcare environments. In this paper, I implemented HL7 interface engine for Alzheimer's disease in elderly care facility. The interface engine is composed of the client system and the server system. The client system inputs user's medical care data for the aged, and builds them into HL7 message stream. HL7 messages in the client system transmitted over TCP/IP protocol to the server system. The server system parses and validates this messages stream to the segments and fields and then transmits acknowledgement to the client system. I implemented it using the Java and JavaCC. The study of interface engine implementation can be used meaningfully in electronic health record, telemedicine system, and medical information sharing among various healthcare institutions.
  • 11.

    A Customized Mobile Tour Guide System for Amusement Park based on GPS

    유석종 | 2010, 15(8) | pp.99~105 | number of Cited : 4
    Abstract PDF
    Because in the amusement park, a number of people use various vehicles facilities complicated arraigned, it needs an effective way to search optimal path to reduce errors in touring a park. Particularly, when choosing a facility, searching a waiting time-based path as well as shortest path is important. This paper presents a path recommendation system which minimizes total park tour time based on tour distance and waiting time through GPS and wireless internet. This system can also recommend customized tour path based on the characteristics of user members as well as a simple shortest path.
  • 12.

    A Secure Technique Design for Privacy Protection in RFID System

    Oh Gi Oug , Mi Og Park | 2010, 15(8) | pp.107~115 | number of Cited : 0
    Abstract PDF
    RFID (Radio Frequency IDentification) technology, automatic identification and data capture technologies in ubiquitous computing is an essential skill. Low-cost Radio Frequency Identification tags using memory and no physical contact due to the ease of use and maintenance of excellence are going to use expanded. However, it is possible to the illegal acquisition of the information between RFID tags and readers because RFID uses the RF signal, and the obtained information can be used for the purpose of location tracking and invasion of privacy. In this paper, we proposed the security scheme to protect against the illegal user location tracking and invasion of privacy. The security scheme proposed in this paper, using Gray Code and reduced the capacity of the calculation of the actual tags, However, it is impossible for the malicious attacker to track information because tag information transmitted from the reader is not fixed. Therefore, even if the tags information is obtained by a malicious way, our scheme provides more simple and safe user privacy than any other protection methods to protect user privacy, because not actual information but encrypted information is becoming exposed.
  • 13.

    A Structural Complexity Metric for Web Application based on Similarity

    Woosung Jung , LEE, EUN JOO | 2010, 15(8) | pp.117~126 | number of Cited : 2
    Abstract PDF
    Software complexity is used to evaluate a target system's maintainability. The existing complexity metrics on web applications are count-based, so it is hard to incorporate the understandability of developers or maintainers. To make up for this shortcomings, entropy-theory can be applied to define complexity, however, it is assumed that information quantity of each paper is identical. In this paper, structural complexity of a web application is defined based on information theory and similarity. In detail, the proposed complexity is defined using entropy as the previous approach, but the information quantity of individual pages is defined using similarity. That is, a page which are similar with many pages has smaller information quantity than a page which are dissimilar to others. Furthermore, various similarity measures can be used for various views, which results in many-sided complexity measures. Finally, several complexity properties are applied to verify the proposed metric and case studies shows the applicability of the metric.
  • 14.

    CoRapport: Proactive Display Application Supporting Presentation of Various Social Web Contents in Physical Spaces

    이태호 , Myung-Joon Lee | 2010, 15(8) | pp.127~139 | number of Cited : 0
    Abstract PDF
    he concept of Web 2.0, which means that internet users are producers and also consumers is evolved according to the development of web service technology. In the Web 2.0 space, the enormous amount of web contents are produced using many social web services. Proactive display system supports various types of users's web contents. Unfortunately, private web contents sharing facility is imperfect to date. In this paper, we develop a proactive display application which identifies people, displaying their social contents such as blogs and open cafes through wide display devices or multi-media players in physical spaces. For this, we develop a social contents presentation server where users can register their profiles and information on the social contents to be shared through the developed application. Also, we develop a social contents presentation client that proactively identifies the user in close proximity and displays the user's social contents through an intuitive user interface in physical spaces. In addition, we develop an on-the-spot feedback service which supports posting various types of replies and an on-the-spot scrap service which specifies direct sharing of the contents through the intuitive user interface.
  • 15.

    User's Individuality Preference Recommendation System using Improved k-means Algorithm

    안찬식 , 오상엽 | 2010, 15(8) | pp.141~148 | number of Cited : 2
    Abstract PDF
    In mobile terminal recommend service system has general information restrictive recommend that individuality considering to user's information find and recommend. Also it has difficult of accurate information recommend bad points user's not offer individuality information preference recommend service. Therefore this paper is propose user's information individuality preference considering by user's individuality preference recommendation system using improved k-means algorithm. Propose method is correlation coefficients using user's information individuality preference when user's individuality preference recommendation using improved k-means algorithm. Restrictive information recommend to fix a problem, information of restrictive general recommend that user's information individuality preference offer to accurate information recommend. Performance experiment is existing service system as compared to evaluating the effectiveness of precision and recall, performance experiment result is appear to precision 85%, recall 68%.
  • 16.

    An Energy Efficient Query Processing Mechanism using Cache Filtering in Cluster-based Wireless Sensor Networks

    이광원 , Yoon-Cheol Hwang , 오염덕 | 2010, 15(8) | pp.149~156 | number of Cited : 0
    Abstract PDF
    As following the development of the USN technology, sensor node used in sensor network has capability of quick data process and storage to support efficient network configuration is enabled. In addition, tree-based structure was transformed to cluster in the construction of sensor network. However, query processing based on existing tree structure could be inefficient under the cluster-based network. In this paper, we suggest energy efficient query processing mechanism using filtering through data attribute classification in cluster-based sensor network. The suggestion mechanism use advantage of cluster-based network so reduce energy of query processing and designed more intelligent query dissemination. And, we prove excellence of energy efficient side with MATLab.
  • 17.

    Design of Charge and Discharge Monitoring System for Secondary Batteries of Hybrid Electric Vehicle

    Lee Jun Ha , 이강호 , Choi Jong Ho | 2010, 15(8) | pp.157~161 | number of Cited : 3
    Abstract PDF
    Most of air pollution in a metropolis is the result of exhaust gas emissions from automotive vehicles, and the world-wide regulation against environmental pollution is becoming more strict. Moreover the demand on development and supply of an environment-friendly automobile is increasing and the market share about that is expected to grow rapidly in this time of high oil price. The secondary batteries the most important component to store the electrical energy in hybrid electric vehicle. It needs to the higher power characteristics to emit the energy instantaneous. In this paper, we proposed the system to monitor reliably the charge and discharge states of the secondary batteries for hybrid electric vehicle. The material is about SW and HW module the software and hardware module mounted on the charge and discharge system and the monitoring system to control the charge and discharge performance effectively.
  • 18.

    A Study on Personas Models for Car Navigation Developing

    오세형 , 김정희 , HakHyunChoi | 2010, 15(8) | pp.163~171 | number of Cited : 2
    Abstract PDF
    This research has studied developing the persona model based on alan cooper's user oriented design which is newly in the limelight in the field of product design process. As developing the persona model, In-depth interview and FGI(focus group interview) has been conducted for extracting car navigation user group's motivation and using attribute. Based on research, three different car navigation user group were divided-low using & understanding the function group, medium using & well understanding the function group, heavy using & well understanding the function group. This research yielded the foundation for setting the persona model and this persona gives the key factor for producing the user oriented user Interface design after all.
  • 19.

    A Study on the Improvement Alternatives using USN Technology on Bicycle and Infrastructures

    정성학 | 2010, 15(8) | pp.173~180 | number of Cited : 4
    Abstract PDF
    This research aims to enhance the security and safety of bicycle facilities by utilizing convergence technology of ubiquitous sensor network in the transportation system. To achieve the aim, U-bike system has developed by utilizing sensor network technology, and the serviceability and safety function of public facilities in the system have enhanced. This research also presents a plan for the construction of U-bike using ubiquitous sensor network and safety infrastructure of facilities by analyzing bicycle traffic reports and characteristics of service through studying the literature on the security of bicycles and the safety of facilities on bicycle lanes. The result of this research will contribute to the enhancement of safety function of bicycle lanes and facilities around National 4 major rivers bicycle lanes in the future.
  • 20.

    A dispatching policy for stochastic scheduling simulation considering machine breakdowns

    고동진 , Lee, Chul Ung | 2010, 15(8) | pp.181~192 | number of Cited : 2
    Abstract PDF
    We develop a dispatching policy for stochastic scheduling simulation especially for a continuous manufacturing system with machine breakdowns. The proposed dispatching policy computes an urgency index with the consideration of re-heating, setup cost and remaining due date. Prioritized by the index, we execute swapping or reassigning material sequences so as to minimize the total penalty cost. To evaluate the performance of the proposed policy, a discrete event simulation is developed. With 200 data sets and 20 iterations, we compare the performance of the urgency policy with those of SPT (Shortest Processing Time) and FCFS (First Come First Serve) which are the most common policies. The result shows that the proposed policy consistently gives the lowest total costs by reducing the penalty costs for lateness.
  • 21.

    The Factors affecting on Internet Addition in Adolescence and how to deal with it - Focusing on Ecosystem Theory -

    Hwie- Seo, Park | 2010, 15(8) | pp.193~200 | number of Cited : 23
    Abstract PDF
    This study is to identify the factors affecting on adolescent internet addition and suggest how to deal with it. This study is based on the ecosystem theory for human development. The factors affecting on adolescent internet addition are the followings: First, self-efficacy, self-esteem and self-control affect on internet addiction in individual system. Second, the affecting factors concerned with home environmental system are the communication level between parents and adolescent, parents' attitude for bringing up, parents' control level for adolescent, parents support etc. Third, the affecting factors concerned with school environmental system academic score, friends' support, teacher's support, adolescent adaptation in school life etc. This study suggest how to deal with internet addiction based on these findings.