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

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2009, Vol.14, No.6

  • 1.

    An Embedded Text Index System for Mass Flash Memory

    윤상훈 , Haengrae Cho | 2009, 14(6) | pp.1~10 | number of Cited : 2
    Abstract PDF
    Flash memory has the advantages of nonvolatile, low power consumption, light weight and high endurance. This enables the flash memory to be utilized as a storage of mobile computing device such as PMP(Portable Multimedia Player). Potable device with a mass flash memory can store various multimedia data such as video, audio, or image. Typical index systems for mobile computer are inefficient to search a form of text like lyric or title. In this paper, we propose a new text index system, named EMTEX(Embedded Text Index). EMTEX has the following salient features. First, it uses a compression algorithm for embedded system. Second, if a new insert or delete operation is executed on the base table, EMTEX updates the text index immediately. Third, EMTEX considers the characteristics of flash memory to design insert, delete, and rebuild operations on the text index. Finally, EMTEX is executed as an upper layer of DBMS. Therefore, it is independent of the underlying DBMS. We evaluate the performance of EMTEX. The Experiment results show that EMTEX can outperform th conventional index systems such as Oracle Text and FT3.
  • 2.

    Agile Performance Simulation Model for a Closed Multi-class System

    Yong-Soo Kim | 2009, 14(6) | pp.11~16 | number of Cited : 1
    Abstract PDF
    The queuing theory was adopted by Erlang to predict the availability of telephone lines in 1917 and had not been used for computer system performance analysis until late 1960s when Scherr published a performance analysis of time-shared computer system. In 2000s, the explosive Internet usage and the development of IT technology made the business environment speed-centric and analysts should react swiftly to the ever-changing situation to satisfy the user requirement. It’s tempting to solve the performance problem by purchasing new devices because the price of computers and peripherals are rapidly decreasing along with their increasing performance. But this scheme not only makes it difficult to understand the overall performance of the system but also wastes money. A coarse performance model that is gotten quickly is sometimes preferred to a complex and precise one that takes longer time to get. This paper examines an analytic model suggested by Menasce based on the measured data and suggests a simulation model using ARENA that takes a short time to build.
  • 3.

    Extraction of Military Ontology Using Six-Step Bottom-up Approach

    나민영 , 양경용 | 2009, 14(6) | pp.17~26 | number of Cited : 6
    Abstract PDF
    In national defense, established information systems are mainly based on simple information processing, such as mass data query. They have thus lacked intelligent ability of information and knowledge representation ability. We therefore need the research about the construction of military ontology which is the main topic for knowledge construction. Military ontology can help us develop the intelligent national defense information system which can search and manage information efficiently. In this paper, we present the six-step bottom-up approach for military ontology extraction, then we apply this approach to one of military domain, called national defense educational training, and finally implement it using Protégé which is one of the most useful ontology development tool.
  • 4.

    3-Factor Authentication Using HMAC-based One-Time Password

    Seiwoong Oh , Kin JiHong | 2009, 14(6) | pp.27~32 | number of Cited : 1
    Abstract PDF
    Recently, most of information services are provided by the computer network, since the technology of computer communication is developing rapidly, and the worth of information over the network is also increasing with expensive cost. But various attacks to quietly intercept the informations is invoked with the technology of communication developed, and then most of the financial agency currently have used OTP, which is generated by a token at a number whenever a user authenticates to a server, rather than general static password for some services. A 2-Factor OTP generating method using the OTP token is mostly used by the financial agency. However, the method is vulnerable to real attacks and therefore the OTP token could be robbed and disappeared. In this paper, we propose a 3-Factor OTP way using HMAC to conquer the problems and analyze the security of the proposed scheme.
  • 5.

    Software Development Process for Project Complexity and Size

    윤석민 , 김인식 | 2009, 14(6) | pp.33~40 | number of Cited : 1
    Abstract PDF
    In this thesis, for the assessment of software development process for project complexity and project size : one of digital watermarking algorithm is selected and examined. Digital watermarking provides a solution to illegal copying of digital contents and has many other useful applications, including web broadcast monitoring, transaction tracking, authentication, copy control and device control. This thesis focused on the method for customizing software development path, considering the project environments and characteristics. The selection standard of software development path is composed of process items, based on the ISO/IEC 15721 Information Technology Guide for ISO/IEC 12207 (Software Life Cycle Process) and ISO/IEC 15504 Information technology - Process assessment. To evaluate the algorithm, a system for selecting development path, which reflected algorithm, was examined.
  • 6.

    Multi-camera Calibration Method for Optical Motion Capture System

    Kiyoung Shin , Joung Hwan Mun | 2009, 14(6) | pp.41~50 | number of Cited : 3
    Abstract PDF
    In this paper, the multi-camera calibration algorithm for optical motion capture system is proposed. This algorithm performs 1st camera calibration using DLT(Direct linear transformation) method and 3-axis calibration frame with 7 optical markers. And 2nd calibration is performed by waving with a wand of known length(so called wand dance) throughout desired calibration volume. In the 1st camera calibration, it is obtained not only camera parameter but also radial lens distortion parameters. These parameters are used initial solution for optimization in the 2nd camera calibration. In the 2nd camera calibration, the optimization is performed. The objective function is to minimize the difference of distance between real markers and reconstructed markers. For verification of the proposed algorithm, re-projection errors are calculated and the distance among markers in the 3-axis frame and in the wand calculated. And then it compares the proposed algorithm with commercial motion capture system. In the 3D reconstruction error of 3-axis frame, average error presents 1.7042mm(commercial system) and 0.8765mm(proposed algorithm). Average error reduces to 51.4 percent in commercial system. In the distance between markers in the wand, the average error shows 1.8897mm in the commercial system and 2.0183mm in the proposed algorithm.
  • 7.

    A Key distribution Scheme for Information Security at Wireless Sensor Networks

    김회복 , 신정훈 , Kim Hyoung Jin | 2009, 14(6) | pp.51~58 | number of Cited : 2
    Abstract PDF
    Wireless sensor networks consist of numerous sensor nodes that have inexpensive and limited resources. Generally, most of the sensors are assigned to the hazardous or uncontrollable environments. If the sensor nodes are randomly assigned to the wide target area, it is very hard to see the accurate locations of sensor nodes. Therefore, this study provides an efficient key distribution scheme to solve these problems. Based on the provided scheme, the study enabled the closely neighboring nodes to exchange information with each other after securing safe links by using the pre-distributed keys. At the same time, the provided scheme could increase the probability of multiparty key detection among nodes by using the location information of sensor node. Lastly, the study intended to show the superiority of the limitation method through a performance test.
  • 8.

    Improvement of Edge Detection Using Mean Shift Algorithm

    SeongYoon Shin , Chang Woo Lee , Rhee Yang Weon | 2009, 14(6) | pp.59~64 | number of Cited : 0
    Abstract PDF
    Edge detection always influenced by the noise of original image, therefore need some methods to eliminate them in advance, and the Mean Shift algorithm has the smooth function which suit for this purpose, so adopt it to fade out the unimportant information and the sensitive noise portions. Above all, we use the Canny algorithm to pick up the contour of the objects we focus on. And, take tests and get better result than the former sole Canny algorithm. This combination method of Mean Shift algorithm and Canny algorithm is suitable for the edge detection processing.
  • 9.

    Using Radon Transform for Image Retrieval

    Seo Jeong-Man | 2009, 14(6) | pp.65~72 | number of Cited : 0
    Abstract PDF
    The basic features in the indexing and retrieval of the image is used color, shape, and texture in traditional image retrieval method. We do not use these features and offers a new way. For content-based video indexing and retrieval, visual features used to measure the similarity of the geometric method is presented. This method is called the Radon transform. Without separation, this method is calculated based on the geometric distribution of image. In the experiment has a very good search results.
  • 10.

    An Efficient TCP Algorithm in Mobile ADHOC Networks

    홍성화 , HoonKi Kim | 2009, 14(6) | pp.73~82 | number of Cited : 1
    Abstract PDF
    TCP assumes that packet loss is always happened by congestionlike wired networks because is can not distinguish between congestion loss and transmission error loss,. This assumption results in unnecessary TCP performance degradation in wireless networks by reducing sender's congestion window size and retransmitting the lost packets. Also, repeated retransmissions loed to waste the limited battery power of mobile devices. In this paper, we propose the new congestion control scheme that add the algorithms monitoring networks states and the algorithms preventing congestion to improve TCP throughput performance and energy efficiency in wireless ad-hoc networks. Using NS2, we showd our scheme improved throughput performance and energy efficiency.
  • 11.

    A Stochastic Serving MPP Selection Method for Increasing the Efficiency of a Wireless Mesh Network

    Jaesung Park , Lim, Yujin | 2009, 14(6) | pp.83~90 | number of Cited : 1
    Abstract PDF
    Since traffic is aggregated to a MPP that acts as an Internet gateway, if traffic load is not balanced among the MPPs in a WMN, the overall performance of a WMN becomes poor even though the total traffic load is far below the capacity of the WMN. Therefore, in this paper, we propose a stochastic load balancing scheme where each MP (Mesh Point) probabilistically selects its serving MPP according to the congestion levels of MPPs. Through extensive simulations using ns-2, we have verified that our scheme can stabilize a WMN fast when congestion occurs and reduce packet loss rate by distributing traffic load of a congested MPP to multiple MPPs in the inverse proportional to their congestion levels. Compared to queue-based load balancing scheme, our method can decrease network stabilization time by 34 seconds, and reduce packet loss rate by 7.6%. Since the proposed scheme can reduce network stabilization time by efficiently using network resource, it is expected to contribute to the reliable operation of a WMN.
  • 12.

    A Lattice-Based Role Graph Security Model ensuring Confidentiality and Integrity

    Choi Eun-Bok | 2009, 14(6) | pp.91~98 | number of Cited : 1
    Abstract PDF
    In this paper, this model ensures confidentiality and integrity of mandatory access cotrol policy which based on fuzzy function with importance of information. And it solves authorization abuse problem through role graph creation algorithm and flowing policy that security grade is applied. Because this model composes role hierarchy which bind similar role concept to apply to commercial environment, it has expansile advantage by large scale security system as well as is easy that add new role.
  • 13.

    Design and Implementation of a Concept Map Assessment System Using the Semantic Web Technologies

    Park Ung Kyu | 2009, 14(6) | pp.99~106 | number of Cited : 0
    Abstract PDF
    Over recent decades, concept mapping has been used as a valuable Learning and Teaching tool. A number of studies have shown a positive impact on student learning. One of the disadvantages of this technique has been that assessing them or providing feedback to students is time consuming. We aim here to introduce ways of reducing the complexity of using concept map techniques in online activities. Several types of scoring methods for the concept map based assessment have been developed. In this paper, we describe the development of an automatic assessment system that implements those techniques. We contribute a design that uses semantic web technologies for both the management and the scoring of the concept maps.
  • 14.

    The Influence of IT Investment on Process Maturity and User Satisfaction

    김원섭 , HaeSool Yang | 2009, 14(6) | pp.107~116 | number of Cited : 1
    Abstract PDF
    Even though there are growing numbers of IT utilization in many organizations, they are required to use only constrained amount of resources due to the decrease in IT Investment, following economic recession. Besides, the CEOs in those organizations are required to assess how IT Investment, which has been gradually increased during the industrial growth, affects their organizational performances. Thus, they began to enforce IT governance so as to measure IT efficiency and minimize business risks. As a result, they improved the decision making process of IT Investment, enforced IT value assessment, and established the IT Investment-performance evaluation process as well. In this article, I aimed to make it clear how IT Investment affects the IT Performance by analyzing the effects of the factors constituting the IT Investment managing system and the Process Maturity on the User Satisfaction. This analysis can suggest a practical IT Investment-performance model, which can increase organizational performances.
  • 15.

    Convert 2D Video Frames into 3D Video Frames

    Heeman Lee | 2009, 14(6) | pp.117~124 | number of Cited : 3
    Abstract PDF
    In this paper, An algorithm which converts 2D video frames into 3D video frames of parallel looking stereo camea is proposed. The proposed algorithm finds the disparity information between two consecutive video frames and generates 3D video frames from the obtained disparity maps. The disparity information is obtained from the modified iterative convergence algorithm. The method of generating 3D video frames from the disparity information is also proposed. The proposed algorithm uses coherence method which overcomes the video pattern based algorithms.
  • 16.

    A Study of Query Processing Model to applied Meta Rule in 4-Level Layer based on Hybrid Databases

    Oh, Ryum-duck | 2009, 14(6) | pp.125~134 | number of Cited : 0
    Abstract PDF
    A biological data acquisition based on web has emerged as a powerful tool for allowing scientists to interactively view entries form different databases, and to navigate from one database to another molecular-biology database links. In this paper, the biological conceptual model is constructed hybrid biological data model to represent interesting entities in the data sources to applying navigation rule property for each biological data source based on four biological data integrating layers to control biological data. When some user's requests for application service are occurred, we can get the data from database and data source via web service. In this paper, we propose a query processing model and execution structure based on integrating data layers that can search information on biological data sources.
  • 17.

    Development of Automatic Rule Extraction Method in Data Mining : An Approach based on Hierarchical Clustering Algorithm and Rough Set Theory

    Seung-Joon Oh , park chan woong | 2009, 14(6) | pp.135~142 | number of Cited : 4
    Abstract PDF
    Data mining is an emerging area of computational intelligence that offers new theories, techniques, and tools for analysis of large data sets. The major techniques used in data mining are mining association rules, classification and clustering. Since these techniques are used individually, it is necessary to develop the methodology for rule extraction using a process of integrating these techniques. Rule extraction techniques assist humans in analyzing of large data sets and to turn the meaningful information contained in the data sets into successful decision making. This paper proposes an autonomous method of rule extraction using clustering and rough set theory. The experiments are carried out on data sets of UCI KDD archive and present decision rules from the proposed method. These rules can be successfully used for making decisions.
  • 18.

    Influence Factors on the IT Governance from ITA/EA Functions

    Yeon S. Ahn , Hee Wan Kim | 2009, 14(6) | pp.143~152 | number of Cited : 2
    Abstract PDF
    In this paper, we brought some influence factors of what the function contributing by ITA/EA in organization is. Also, we verified statistically the impact relation in mutual on the base of questionnaire, extracting in investigation the factors of why the IT Governance of organization is building up, and by what the effect of building up is estimated. In result of statistical analysis based on the 223 case of organizations, it appeared that the infrastructure management, decision making enhancement, and IT process and service functions are the contributing factors on the IT Governance.
  • 19.

    A study of the highway advisory radio system implementation for traffic information service

    정성학 | 2009, 14(6) | pp.153~164 | number of Cited : 4
    Abstract PDF
    The objective of this study is to provide systematic design of the Korea's highway advisory radio system in intelligent transport systems. Highway advisory radio services support safety driving and traffic information for travellers, and rapid response of the system for emergency status not only dissemination of traffic for traffic but also flood, heavy snowfall, falling rocks, closed-road, collapse, accident and so on. Therefore, highway advisory radio service contributes national highway safety management system to the voice of the nation of user-centered traffic information service.
  • 20.

    heoretical Implication on Establishing the National Countermeasure System against Cyber Crime - Focusing on a Pattern of Cyber Terror -

    Young Hwan Kim | 2009, 14(6) | pp.165~171 | number of Cited : 10
    Abstract PDF
    From the late 20th century, rapidly progressing information communication technology and spreading Internet all over the world cause many reverse functions when there is a conversion into the new information society. One of them is cyber terrorism as cyber crime. Cyber terrorism gradually has had a serious problem in the national security as well as the domestic aspects. Therefore, this study looked into the present condition of cyber terrorism, discussed its prospect, and sought the efficient national countermeasure methods against cyber terrorism by comparing other countries' countermeasure systems currently.