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

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2009, Vol.14, No.2

  • 1.

    The Development of a Dormitory Management System Using the Ubiquitous and Automation Technology

    장재혁 , 심갑식 | 2009, 14(2) | pp.1~8 | number of Cited : 2
    Abstract PDF
    Today, the use of RFID is extended in medical, circulation market, manufacture, security field, etc. Besides, the book-lending and the attendance management system are on an increasing trend in the use of RFID. The developed dormitory management system is composed of a support program, a room management program, a manager program, and a mobile program etc.. In the support program a student(or a manager) can see his(or all member's) entrance and exit history. The room management program decides whether a student can enter the dormitory or not and manages the use of the power after inquiring a RFID's input tag information into database server. The manager program is able to input and modify a room state and the fixtures information in the room required to operate the room management program, to set up and retrieve a student's entrance and exit information and a room state information. The mobile program enables a manager to check student's identity whether he is in or out, and the manager can know the personal information of being out in detail.
  • 2.

    Research on the Design of TPO(Time, Place, 0Occasion)-Shift System for Mobile Multimedia Devices

    KimDaeJin , Choi Hong Sub | 2009, 14(2) | pp.9~16 | number of Cited : 4
    Abstract PDF
    While the broadband network and multimedia technology are being developed, the commercial market of digital contents as well as using IPTV has been widely spreading. In this background, Time-Shift system is developed for requirement of multimedia. This system is independent of Time but is not independent of Place and Occasion. For solving these problems, in this paper, we propose the TPO(Time, Place, Occasion)-Shift system for mobile multimedia devices. The profile that can be applied to the mobile multimedia devices is much different from that of the settop-box. And general mobile multimedia devices could not have such large memories that is for multimedia data. So it is important to continuously store and manage those multimedia data in limited capacity with mobile device's profile. Therefore we compose the basket in a way using defined time unit and manage these baskets for effective buffer management. In addition, since the file name of basket is made up to include a basket's time information, we can make use of this time information as DTS(Decoding Time Stamp). When some multimedia content is converted to be available for portable multimedia devices, we are able to compose new formatted contents using such DTS information. Using basket based buffer systems, we can compose the contents by real time in mobile multimedia devices and save some memory. In order to see the system's real-time operation and performance, we implemented the proposed TPO-Shift system on the basis of mobile device, MS340. And settop-box are designed by using directshow player under Windows Vista environment. As a result, we can find the usefulness and real-time operation of the proposed systems.
  • 3.

    The Effects of Robot Programming Learning using Pico Cricket on Problem Solving Ability and Interest

    이진영 , 송정범 , 김광열 and 2 other persons | 2009, 14(2) | pp.17~26 | number of Cited : 11
    Abstract PDF
    This paper is experimental study to inspect effects of problem solving ability and programming interest using Pico Cricket of the educational robot. The programming learning which is regarded as the very core of information subject improves problem solving ability. But the programming learning does not display the effects properly, because the programming learning studies a grammar manual. The educational robot has the advantage to approach the programming learning easily for containing entertainment. The Pico Cricket of the educational robot has the advantage not to induce competition but to compose a cooperative learning environment. Also, the Pico Cricket is able to be had interest of programming learning to girl students, because the Pico Cricket is able to suggest life-centered and cooperative contents which girl students like. Accordingly, This paper is study which the programming learning using Pico Cricket affects the problem solving ability and programming interest and men and women's comparison study.
  • 4.

    AIntegration of Integer Programming and Neighborhood Search Algorithm for Solving a Nonlinear Optimization Problem

    Hwang Junha | 2009, 14(2) | pp.27~35 | number of Cited : 1
    Abstract PDF
    Integer programming is a very effective technique for searching optimal solution of combinatorial optimization problems. However, its applicability is limited to linear models. In this paper, I propose an effective method for solving a nonlinear optimization problem by integrating the powerful search performance of integer programming and the flexibility of neighborhood search algorithms. In the first phase, integer programming is executed with subproblem which can be represented as a linear form from the given problem. In the second phase, a neighborhood search algorithm is executed with the whole problem by taking the result of the first phase as the initial solution. Through the experimental results using a nonlinear maximal covering problem, I confirmed that such a simple integration method can produce far better solutions than a neighborhood search algorithm alone. It is estimated that the success is primarily due to the powerful performance of integer programming.
  • 5.

    Enhancement of Real-Time Transmission Performance of PGA data

    임인섭 , Soon Key Jung , 최인영 | 2009, 14(2) | pp.37~44 | number of Cited : 1
    Abstract PDF
    In this paper, we propose an efficient method which improves the performance of transmission of PGA which is essential data for real-time earthquake monitoring system. Currently, above 120 earthquake stations were installed nationwide and additional installation is expected because the social interesting of earthquake hazard is rising. Real-time earthquake monitoring system checks earthquake occurrence by using PGA were calculated from acceleration data of each seismic station. An efficient method of PGA data transmission is key factor of real-time monitoring. The key idea of proposed method is to deal with each seismic station using an unique ID, to assign one bit to indicate whether a packet include a station's data or not. Proposed method can contain more station data and decrease the data loss compared to current method. To verify proposed method, we investigate the turnaround time and ratio of data loss using above 91000 packets. As results of experiment, the proposed method is proven that the method need more time about 50% but reduce the data loss about 87% as compared to previous method.
  • 6.

    A Low-Power Texture Mapping Technique for Mobile 3D Graphics

    김현희 , Kim, Jihong | 2009, 14(2) | pp.45~57 | number of Cited : 1
    Abstract PDF
    ETexture mapping is a technique used for adding reality to an image in 3D graphics. However, this technique becomes the bottleneck of the 3D graphics pipeline because it requires large processing power and high memory bandwidth. For reducing memory latency in texture mapping, texture cache is used. As portable devices become smaller and they have power constraint, it is important to reduce the area and the power consumption of the texture cache. In this paper, we propose using a small texture cache to reduce the area and the power consumption of the texture cache. Furthermore, we propose techniques to keep a performance comparable to large texture caches by using prefetch techniques and a victim cache. Simulation results show the proposed small texture cache can reduce the area and the power consumption up to 70% and 60%, respectively, by using 1~2K bytes texture cache compared to the conventional 16K bytes cache while keeping the performance.
  • 7.

    Development and Validation of an Scale to Measure Flow in Massive Multiplayer Online Role Playing Game

    정미경 , Myung-geun Lee , Kim Sung Wan | 2009, 14(2) | pp.59~68 | number of Cited : 6
    Abstract PDF
    This paper aims to explore the factors of learner's flow and to develop and validate a scale to measure the flow in Massive Multiplayer Online Role Playing Game(MMORPG) for education. First of all, potential factors were drawn through literature review. The potential scale comprises 6 factors(learner's psychological characteristics, learner's skill, importance of game, environment for learner, instructional design, and instructional environment) and 16 subfactors. With total 48 items developed, a survey was carried out among 293 elementary learners who had been participating in a commercial MMORPG for English skills to measure their flow in the MMORPG by utilizing the potential scale. Using the responses collected from 288 respondents, exploratory factor analysis, reliability analysis, and confirmatory factor analysis were performed. The expository factor analysis showed that items within each sub-factors could be bound into one factor. That is, the variables evaluating learner's flow were divided into six factors(learner's psychological characteristics, learner's skill, importance of game, environment for learner, instructional design, and instructional environment). And these factors were interpreted consisting of 16 sub-ones. Reliability estimates indicated that the evaluation tool had good internal consistency. The confirmatory factor analysis did confirm the model suggested by the expository factor analysis. Over fit measures(CFI, NFI, NNFI) showed the good suitability of the model. Findings of this study confirmed the validity and reliability of the scale to measure learner's flow in MMORPG.
  • 8.

    A Multi-dimensional Query Processing Scheme for Stream Data using Range Query Indexing

    Dong-Un Lee , Yunseok Rhee | 2009, 14(2) | pp.69~77 | number of Cited : 2
    Abstract PDF
    Stream service environment demands real-time query processing for voluminous data which are ceaselessly delivered from tremendous sources. Typical R-tree based query processing technologies cannot efficiently handle such situations, whichㅁㅁ require repetitive and inefficient exploration from the tree root on every data event. However, many stream data including sensor readings show high locality, which we exploit to reduce the search space of queries to explore. In this paper, we propose a query processing scheme exploiting the locality of stream data. From the simulation, we conclude that the proposed scheme performs much better than the traditional ones in terms of scalability and exploration efficiency.
  • 9.

    CoSpace: A Windows WebDAV Client Supporting Effective Collaborative Works

    이홍창 , 박진호 , Myung-Joon Lee | 2009, 14(2) | pp.79~89 | number of Cited : 1
    Abstract PDF
    As an IETF standard protocol, WebDAV provides infrastructure for managing and authoring resources and supports asynchronous collaborative authoring on the Web. The CoSlide server is an extension of the Jakarta Slide WebDAV server, providing various workspaces and collaborative services through the WebDAV protocol. The CoSlide server supports workspaces for storing and sharing information of various users, and provides environment for effective collaborative authoring. Actual collaboration activities are performed through a collaboration client software which provides collaboration services along with the CoSlide server. In this paper, we describe the development of the CoSpace client which operates in association with the CoSlide server, presenting effective collaborative environment. The CoSpace client provides user interfaces for accessing and controlling the resources of each workspace on the CoSlide server. In particular, CoSpace provides the facility to launch an authoring application from its workspace view, automatic locking, and downloading the content to be edited, and resource movement using mouse drag & drop.
  • 10.

    Understanding the intention to use Multimedia messaging services

    kyung kyu kim , Ho Kyoung Shin , Beomsoo Kim | 2009, 14(2) | pp.91~101 | number of Cited : 8
    Abstract PDF
    MMS (Multimedia Messaging Services) is one of the most basic services of mobile communication as well as a promising m-commerce enabling service. In our study, we hypothesize that the personality-based and cognitive traits of TAM and social cognitive theory are antecedents to MMS acceptance asking: what are the key determinants of intention to use MMS? An empirical investigation of 1,016 mobile phone users in South Korea was conducted. PLS results provided support for the effects of self-efficacy, perceived ease of use, relative advantage, credibility on attitude toward MMS use and strong support for the effect of attitude toward intention to use MMS. Our results provided a detailed account of the key forces underlying users’ intention to use MMS including personal and cognitive trait measures. Theoretical and practical implications of these findings are discussed in the paper.
  • 11.

    Effective Dynamic Broadcast Method in Hybrid Broadcast Environment

    최재훈 , 이진승 , 강재우 | 2009, 14(2) | pp.103~110 | number of Cited : 1
    Abstract PDF
    We are witnessing rapid increase of the number of wireless devices available today such as cell phones, PDAs, Wibro enabled devices. Because of the inherent limitation of the bandwidth available for wireless channels, broadcast systems have attracted the attention of the research community. The main problem in this area is to develop an efficient broadcast program. In this paper, we propose a dynamic broadcast method that overcomes the limitations of static broadcast programs. It optimizes the scheduling based on the probabilistic model of user requests. We show that dynamic broadcast system can indeed improve the quality of service using user requests. This paper extends our previous work in [1] to include more thorough explanation of the proposed methodology and diverse performance evaluation models.
  • 12.

    Implementation of Propagation delay estimation model of medium frequency for positioning

    Donghui Yu | 2009, 14(2) | pp.111~118 | number of Cited : 0
    Abstract PDF
    Against Anomaly of GPS, there are several projects of independent satellite navigation systems like Galileo of Europe and QZSS of Japan and modernization of terrestrial navigation system like Loran. In domestic, the need of independent navigation system was proposed and DGPS signal was nominated as the possible substitute. The DGPS signal uses medium frequency, which travels through the surface and cause the additional delay rather than the speed of light according to conductivities and elevations of the irregular terrain. The similar approach is Locan-C. Loran-C has been widely used as the maritime location system. Loran-C uses the ASF estimation method and provides more precise positioning. However there was rarely research on this area in Korea. Therefore, we introduce the legacy guaranteed model of additional delay(ASF) and present the results of implementation. With the comparison of the original Monteath results and BALOR results respectively, we guarantee that the implementation is absolutely perfect. For further works, we're going to apply the ASF estimation model to Korean DGPS system with the Korean terrain data.
  • 13.

    A Method for Security Strengthening of Web Application using AOP

    선수림 , LEE KEUM SUK | 2009, 14(2) | pp.119~128 | number of Cited : 1
    Abstract PDF
    As use of web applications and web-based information systems increases, so web application attacks are increasing. Recently, XSRF(Cross Site Request Forgery) attacks among a variety of web attacks become important because victim’s damage caused by such attacks can be severe. But adding security functions for preventing XSRF attacks to existing developed and running software systems could affect more dangerous and expensive to companies and organizations. We suggest effectively adding these security functions to legacy systems, could separate concerns using advantage of the modularity offered by AOP(Aspect-Oriented Programming) methodology. In this paper, we have presented approach for detecting and preventing XSRF in JEE systems using aspect of AOP.
  • 14.

    A Study on Establishing Resident's Behavioral Model in Daily Living based on a Wireless Sensor Network

    Cho Seung Ho | 2009, 14(2) | pp.129~138 | number of Cited : 2
    Abstract PDF
    While the issue of caring for the elderly that faces the modern society has reached a serious level, it is expected that it will be particularly true in the Republic of Korea where an aged, not an aging, society is impending. In this paper I did research on establishing behavioral model of residents who dwell in home or welfare facilities. I suggested a behavioral model in daily living, , based on event triggering. A multi-hop routing-based wireless luminance/temperature sensor network was built based on the proposed resident's behavioral model. I did experiments on behavioral activities of residents on the wireless sensor network system. According to experimental results, I could classify whether the daily activity of a resident someday is regular or not. These experimental results show that the proposed behavioral model is highly applicable in caring for residents in home or welfare facilities effectively in the future.
  • 15.

    A Physical Data Design and Query Routing Technique of High Performance BLAST on E-Cluster

    TaeKyung Kim , Cho, Wan-sup | 2009, 14(2) | pp.139~147 | number of Cited : 1
    Abstract PDF
    BLAST (Basic Local Alignment Search Tool) is a best well-known tool in a bioinformatics area. BLAST quickly compares input sequences with annotated huge sequence databases and predicts their functions. It helps biologists to make it easy to annotate newly found sequences with reduced experimental time, scope, and cost. However, as the amount of sequences is increasing remarkably with the advance of sequencing machines, performance of BLAST has been a critical issue and tried to solve it with several alternatives. In this paper, we propose a new PC-Based Cluster system (E-Cluster), a new physical data design methodology (logical partitioning technique), and a query routing technique (intra-query routing). To verify our system, we measure response time, speedup, and efficiency for various sizes of sequences in NR (Non-Redundancy) database. Experimental result shows that proposed system has better speedup and efficiency (maximum 600%) than those of conventional approaches such as SMP machines, clusters, and grids.
  • 16.

  • 17.

    A Study on the Power Converter Control of Utility Interactive Photovoltaic Generation System

    Seung-Kwon Na , 구기준 , Kim Kye Kook | 2009, 14(2) | pp.157~167 | number of Cited : 2
    Abstract PDF
    In this paper, a photovoltaic system is designed with a step up chopper and single phase PWM(Pulse Width Modulation) voltage source inverter. Where proposed Synchronous signal and control signal was processed by one-chip microprocessor for stable modulation. The step up chopper operates in continuous mode by adjusting the duty ratio so that the photovoltaic system tracks the maximum power point of solar cell without any influence on the variation of insolation and temperature because solar cell has typical voltage and current dropping character. The single phase PWM voltage source the inverter using inverter consists of complex type of electric power converter to compensate for the defect, that is, solar cell cannot be developed continuously by connecting with the source of electric power for ordinary use. It can cause the effect of saving electric power, from 10 to 20[%]. The single phase PWM voltage source inverter operates in situation that its output voltage is in same phase with the utility voltage. In order to enhance the efficiency of photovoltaic cells, photovoltaic positioning system using sensor and microprocessor was designed so that the fixed type of photovoltaic cells and photovoltaic positioning system were compared. In result, photovoltaic positioning system can improved 5% than fixed type of photovoltaic cells. In addition, I connected extra power to the system through operating the system voltage and inverter power in a synchronized way by extracting the system voltage so that the phase of the system and the phase of single-phase inverter of PWM voltage type can be synchronized. And, It controlled in order to provide stable power to the load and the system through maintaining high power factor and low output power of harmonics.
  • 18.

    A Study on Paper Retrieval System based on OWL Ontology

    Bokkeun Sun , 위다현 , Han Kwang Rok | 2009, 14(2) | pp.169~180 | number of Cited : 12
    Abstract PDF
    The conventional paper retrieval is the keyword-based search and as a huge amount of data be published, this search becomes more difficult in retrieving information that user want to find. In order to search for information to the user's intent, we need to introduce semantic Web that represents semantics of Web document resources on the Internet environment as ontology and enables the computer to understand this ontology. Therefore, we describe a paper retrieval system through OWL(Ontology Web Language) ontology-based reason in this paper. We build the paper ontology based on OWL which is new popular ontology language for semantic Web and represent the correlation among diverse paper properties as the DL(description logic) query, and then this system infers the correct results from the paper ontology by using the DL query and makes it possible to retrieve information intelligently. Finally, we compared our experimental result with the conventional retrieval.
  • 19.

    Design and Implementation of Emergency Recognition System based on Multimodal Information

    김영운 , Kang Sun-Kyung , 소인미 and 4 other persons | 2009, 14(2) | pp.181~190 | number of Cited : 1
    Abstract PDF
    This paper presents a multimodal emergency recognition system based on visual information, audio information and gravity sensor information. It consists of video processing module, audio processing module, gravity sensor processing module and multimodal integration module. The video processing module and gravity sensor processing module respectively detects actions such as moving, stopping and fainting and transfer them to the multimodal integration module. The multimodal integration module detects emergency by fusing the transferred information and verifies it by asking a question and recognizing the answer via audio channel. The experiment results show that the recognition rate of video processing module only is 91.5% and that of gravity sensor processing module only is 94%, but when both information are combined the recognition result becomes 100%.
  • 20.

    A Light Weighted Robust Korean Morphological Analyzer for Korean-to-English Mobile Translator

    여상화 | 2009, 14(2) | pp.191~199 | number of Cited : 8
    Abstract PDF
    In this paper we present a light weighted robust Korean morphological analyzer for mobile devices such as mobile phones, smart phones, and PDA phones. Such mobile devices are not suitable for natural language interfaces for their low CPU performance and memory restriction. In order to overcome the difficulties we propose 1) an online analysis by using Key Event Handler mechanism, 2) and a robust analysis of the Korean sentences with spacing errors without its correction pre-processing. We adapt the proposed Korean analyzer to a Korean-English mobile translator, which shows 5.8% memory usage reduction and 19.0% enhancement of average response time.
  • 21.

    Design of Iterative Learning Contents and Items Generation System based on SCORM

    BAEK, Yeong Tae , SeHoon Lee , Jae Cheol Jung | 2009, 14(2) | pp.201~209 | number of Cited : 0
    Abstract PDF
    According to previous researches about online evaluation in many e-Learning contents, it took too much time and effort to generate test questions for formative or achievement tests using a database as an item pool. Furthermore, it is hard to measure accomplishment of learners for each unit through overall tests provided by existing e-learning contents. In this paper, to efficiently cope with problems described above, the item pool based on Item Form was transformed into Interaction Date Model in Run-Time Environment of SCORM2004. And the contents for the math concepts and principles that students would learn from regular classroom were developed in accordance with SCORM. In addition, Confidence Factor Function was used to take an objective view in measuring the accomplishment of learners through the items automatically generated by LMS(Learning Management System).
  • 22.

    An Operation Plan of Physical Distribution System for the Efficeient Treating of Stockout

    김병찬 , 이선범 , Choi,Jin-Yeong | 2009, 14(2) | pp.211~219 | number of Cited : 1
    Abstract PDF
    The logistic environment of Korean companies faces very challenging circumstances due to lack of resources and tough price competitions. It is obvious that such a load of logistic cost becomes an obstacle to national or business competition advantages in the era of unlimited market competition. Prior studies concerning these issues sought to express a large-scale distribution network in a unified numerical formula using defined symbols and could take systematic approaches to distribution network. But inventory policy and operation in material distribution system have been limited to conventional methodology, so they are exposed to many questions in practical applications. This study analyzed distribution system cost and developed a relevant model for operation policy of distribution system for the efficeient treating of stockout, allowing practical applications, so that it will contribute to saving operational cost related to material distribution system.
  • 23.

    A Study on the Factors Inf-luencing Intention to Use Internet VOD Movies

    황준석 , Zoon Ky Lee , Jaekyung Lee | 2009, 14(2) | pp.221~229 | number of Cited : 4
    Abstract PDF
    The development of the Internet and telecommunication technology has lead to the diversification of the distribution channel of movies. Internet users can easily watch movies through the Internet VOD(Video On Demand) theaters without a restriction of time and space. In this study, we try to understand the intention to use of internet VOD movies using the concepts of Technology Acceptance Model and Flow Model. We also consider the concepts of sensitivity of holdback period and availability of various choice in movie genre, along with demographic factors such as age and gender. Through our study we enhance our understanding on how and when users use the Internet VOD for their movie watching.