Study on Construction Method of Satellite Radio Interferer Search System
강철규 Chul Gyu Kang , 박철순 Chul Sun Park , 오창헌 Chang Heon Oh
15(3) 343-348, 2011
강철규 Chul Gyu Kang , 박철순 Chul Sun Park , 오창헌 Chang Heon Oh
DOI: JANT Vol.15(No.3) 343-348, 2011
In this paper, we propose the construction and reconstruction method of satellite radio interferer search system to deal with the keen competition among nations to acquire the limited satellite sources. To construct the satellite interferer search system, whole TLS system construction, part of TLS system construction, and domestic system construction methods are proposed. After that characteristics, advantages, and disadvantages of the system are analyzed when these proposed systems are constructed. In addition, database problems are analyzed in case of the reliability of the operating database, the convergence management between database management systems, and public database service then the solution are proposed.
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H-Polarized Scattering by a Resistive Strip Grating with Zero Resistivity at Strip-Edges Over a Grounded Dielectric Plane
윤의중 Uei Joong Yoon
15(3) 349-354, 2011
윤의중 Uei Joong Yoon
DOI: JANT Vol.15(No.3) 349-354, 2011
In this paper, H-polarized scattering problems by a resistive strip grating with zero resistivity at strip-edges over a grounded dielectric plane according to the strip width and grating period, the relative permittivity and thickness of a dielectric layer, and incident angles of a transverse electric (TE) plane wave are analyzed by applying the Fourier-Galerkin Moment Method (FGMM). The tapered resistivity of resistive strips has zero resistivity at strip edges, then the induced surface current density on the resistive strip is expanded in a series of Chebyshev polynomials of the second kind as a orthogonal ploynomials. The sharp variations of the reflected power are due to resonance effects were previously called wood`s anomallies, the numerical results for the reflected power are compared with those of uniform resistivity in the existing papers.
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Object version Transcoding for Streaming Media Service in Wireless Mobile Networks
이종득 Chong Deuk Lee
15(3) 355-363, 2011
이종득 Chong Deuk Lee
DOI: JANT Vol.15(No.3) 355-363, 2011
Transcoding in the wireless mobile network is an important mechanism that reduces the delay time and improves the stream processing capacity. Wireless mobile streaming media services, however, have such problems as congestion, interference and delay due to narrow network bandwidth and limited resources. These problems degrade not only Quality of Service (QoS) but also responsiveness of the streaming media service. To solve this problem, this paper proposes a object version transcoding method. The proposed method analyzes the object versions to construct the transcoding graph. This paper utilizes a reference rate-based control function for an efficient streaming, and measures MVDS(Multiple Version Delay Saving) for an efficient delay savings. The simulation results show that the proposed mechanism achieves improved performance in delay rate and cache hit rate compared with those of other existing methods.
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Multi-Level Streaming Using Fuzzy Similarity in P2P Distribution Mobile Networks
이종득 Chong Deuk Lee
15(3) 364-371, 2011
이종득 Chong Deuk Lee
DOI: JANT Vol.15(No.3) 364-371, 2011
In P2P distribution mobile networks, QoS of streaming media services are under heavy influence from overheads such as congestion, latency, and interference. The problem is further complicated by the fact that the popularity of media objects changes over time. This paper proposes a new FSMS+ (Fuzzy Similarity-based Multi-level Streaming Scheme) which minimizes performance degradation of streaming services due to overhead. We then utilize fuzzy similarity-based relevance that can dynamically stream the streaming media object with minimum overhead. The simulation result showed that the proposed scheme has better performance in retransmission rate, congestion control rate and latency rate than the other existing methods of distance method, DC [disk caching] method, and prefix method.
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Study on the OWASP and WASC-oriented Web Application Security
이재현 Jae Hyun Lee
15(3) 372-377, 2011
이재현 Jae Hyun Lee
DOI: JANT Vol.15(No.3) 372-377, 2011
Until now, the study and research on the projects which have internationally conducted are in poor condition with regard to the security vulnerability analysis of web application. This is due to a lack of precedent study for improving the quality of the web services in order to provide better services for the future. In this paper, I analyze the types of the web application vulnerabilities which have been studied and mapped out a plan for protecting them.
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A Countermeasure to the Stealth Sniff of the Private Media Information
이경률 Kyung Roul Lee , 임강빈 Kang Bin Yim
15(3) 378-385, 2011
이경률 Kyung Roul Lee , 임강빈 Kang Bin Yim
DOI: JANT Vol.15(No.3) 378-385, 2011
This paper introduces technical aspects of the privacy exposure problem of the video and the audio information on the personal computer and proposes a countermeasure to them. According to the increased number of peripherals for computers, especially including the cameras and the mikes, it is required to be careful on the privacy exposure. Currently, some incorporated or standalone cameras have a pilot lamp to indicate their usage. However, many other cameras and all mikes have not equipped with the pilot lamp or other dedicated indicator. Even though this problem doesn`t obstruct their assigned functionalities, it should make the devices susceptible to be exposed with the information they are gathering without any notice to the owners. As a countermeasure to the problem, this paper proposes a reasonable solution that alarms the access trials to the devices and implements programs for the practical sniffing and its counterpart.
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Channel Allocation Method for OFDMA Based Contiguous Resources Units with H-ARQ to Enhance Channel Throughput
김상현 Sang Hyun Kim , 정영호 Young Ho Jung
15(3) 386-391, 2011
김상현 Sang Hyun Kim , 정영호 Young Ho Jung
DOI: JANT Vol.15(No.3) 386-391, 2011
CRU [contiguous resource unit] composed of adjacent OFDMA subcarriers is popularly adopted for recently developed cellular communication standards, e.g. IEEE 802.16e/m. If multiple CRUs having different SNR are assigned to a mobile station, and multiple packet streams are independently transmitted by using H-ARQ transmission, an achievable data rate can be varied according to the channel allocation method of re-transmission packets and new transmission packets. In this paper, the optimum channel allocation method for the above stated problem, and several sub-optimum channel allocation methods to reduce the computational complexity of the optimum allocation method are proposed. According to the simulation results, a sub-optimum allocation method assigning a CRU having good SNR to new transmission packet shows marginal performance loss compared with optimum method, however, the computational complexity can be significantly reduced.
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A Joint ML and ZF/MMSE Detection Algorithm in Uplink for BS Cooperative System
김점수 Jum Su Kim , 김정곤 Jeong Gon Kim , 김석우 Seok Woo Kim
15(3) 392-404, 2011
김점수 Jum Su Kim , 김정곤 Jeong Gon Kim , 김석우 Seok Woo Kim
DOI: JANT Vol.15(No.3) 392-404, 2011
In this paper, we address the issue of joint detection schemes for uplink cellular system when base station cooperation is possible for multi-user detection in multi-cell scenario. The ZF, ML, MMSE and SIC detection are analyzed and evaluated as a conventional scheme. ML attains the optimal performance but the complexity increases exponentially, ZF/MMSE have simple structure but have poor detection performance and SIC has better performance but it has large complexity and potential of the error propagation. However, they need the increased decoder complexity as the number of iteration is increased. We propose a new joint ML and ZF/MMSE detection scheme, which combines the partial ML decoding and ZF/MMSE detection, in order to decrease the decoder complexity. Simulation results show that the proposed scheme attains same or a little bit better BER performance and expect reduced decoder complexity, specially in the case of large number of Base Station are cooperated each other.
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A Study of Security Level Conversion Scheme for Security Documents
조도은 Do Eun Cho , 여상수 Sang Soo Yeo
15(3) 405-411, 2011
조도은 Do Eun Cho , 여상수 Sang Soo Yeo
DOI: JANT Vol.15(No.3) 405-411, 2011
The value of information becomes very high, a large number of research works has been made for acquiring, managing, and using information. In a specific company (or organization), they are classifying company data documents with managed security levels, and they are securing their secured documents. In this paper, we introduce essential technologies enabling to inspect documents securely and to change specific keywords to normal words, in case that a higher security level document should be converted to a lower security level document.
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A study on the Digital Signage using Wireless Networks
이동우 Dong Woo Lee , 이학재 Hak Jae Lee , 고규천 Kyu Cheon Ko , 나종화 Jong Whoa Na
15(3) 412-418, 2011
이동우 Dong Woo Lee , 이학재 Hak Jae Lee , 고규천 Kyu Cheon Ko , 나종화 Jong Whoa Na
DOI: JANT Vol.15(No.3) 412-418, 2011
In the airport, digital signage is used to provide the flight-related information for the passengers. Because the current digital signage is based on wired networking or storage medium, its use is limited in terms of the location and the usage of the digital signage. In order to overcome these limitation, we present a WiBro-based digital signage for the wireless broadband networking and the mobility of the digital signage. We perform comparative experiments with the WiBro-based digital signage and WLAN-based digital signage under various locations, datarate, advertisement contents. The experimental results showed that the WiBro-based digital signage is preferred when the mobility is required, while the WLAN-based digital signage has advantage in datarate.
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A Study on the RTMD(Requirement Tracing Matrix Design) Base on UML
허계범 Kwae Bum Heo , 김영규 Young Gyu Kim , 양동일 Dong Il Yang
15(3) 419-431, 2011
허계범 Kwae Bum Heo , 김영규 Young Gyu Kim , 양동일 Dong Il Yang
DOI: JANT Vol.15(No.3) 419-431, 2011
Design traceability has been widely recognized as being an integral aspect of software development. Also many projects for software application development have failed because that the projects did not analyze user requirements sufficiently and reflected them in the projects adequately. This thesis proposes a specification and tracing technique for object-oriented analysis and design. The subject of this study is the artifacts of UML development methodology. Therefore, to improve the quality of the software development cycle, in short, the system requirement of customers will be able to respond quickly.
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Performance Analysis of Road Lane Recognition using Road Condition Constraint
강우용 Woo Yong Kang , 이은성 Eun Sung Lee , 박재익 Jae Ik Park , 한지애 Ji Ae Han , 홍운기 Woon Ki Hong , 김현수 Hyun So Kim , 허문범 Moon Beon Heo , 남기욱 Gi Wook Nam
15(3) 432-440, 2011
강우용 Woo Yong Kang , 이은성 Eun Sung Lee , 박재익 Jae Ik Park , 한지애 Ji Ae Han , 홍운기 Woon Ki Hong , 김현수 Hyun So Kim , 허문범 Moon Beon Heo , 남기욱 Gi Wook Nam
DOI: JANT Vol.15(No.3) 432-440, 2011
This paper focus on lane recognition performance test using a road lane constraint with transport infrastructure information. The constraint is determined through the relation of the drive direction and vehicle position. The road lane constraint sets large limit for first and last lane. To analyze the performance of the proposed method, simulations are carried out. The results show that the lane recognition performance using a constraint is improved 40% at four-lane, 25% at six-lane, 15% at eight-lane.
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A Study on the Dynamic Characteristics of Polydyne cam Valve Train
유환신 Hwan Shin You , 천동준 Dong Joon Chun
15(3) 441-448, 2011
유환신 Hwan Shin You , 천동준 Dong Joon Chun
DOI: JANT Vol.15(No.3) 441-448, 2011
It is very important that establishing the valve train equations and representing the behavior of the valve train parts. To maintain the specific efficiency of running engine, the cam profile of valve train has more specific influence on the adequate behavior of the valve train than a valve clearance, heat-resistance and durability of parts. The polynomial cam, the multipol cam and polydyne cam profie are widely used to represent cam behaviour. In this study, using polydyne cam design profile equations which is more adequate for representing high speed engine, the geometrical modeling and mathmatical variable analysis are established to analysis the valve behaviour.
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Fuel Flow Control of Turbojet Engine Using the Fuzzy PI+D Controller
정병인 Byeong In Jung , 지민석 Min Seok Jie
15(3) 449-455, 2011
정병인 Byeong In Jung , 지민석 Min Seok Jie
DOI: JANT Vol.15(No.3) 449-455, 2011
In this paper, Proposed controller prevent compressor surge and reduce the acceleration time of the fuel flow control system for turbo-jet engine. Turbo-jet engine controller is designed by applying fuzzy PI+D control algorithm and make an inference by applying Mamdani`s inference method and the defuzzification using the center of gravity method. Fuzzy inference results are used as the fuel flow control inputs to prevent compressor surge and flame-out for turbo-jet engine and the controller is designed to converge to the desired speed quickly and safely. Using MATLAB to perform computer simulations verified the performance of the proposed controller.
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Design and Implementation of single antenna RFID Shelf for FIFO Management of marine materials
장원태 Won Tae Jang
15(3) 456-461, 2011
장원태 Won Tae Jang
DOI: JANT Vol.15(No.3) 456-461, 2011
In this paper, design and Implementation of single antenna RFID Shelf for FIFO management of marine materials, and propose a design as one effective solution of the problem. The goals of the proposed design and system are as follows: cost saving, RFID data validation. Cost problem occurs by the use of many RFID readers. Data problems in the steel structure is generated by the use of radio wave (RFID). In addition, material data from RFID Shelf system, is expected to be used FIFO design information for the vessel information system. Through the proposed RFID Shelf System, it is expected to systematic management and efficient business processes for the vessel information system.
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A Exploratory Study of Confidential Document Circulation System Design
장항배 Hang Bae Chang , 김흥국 Heung Gook Kim
15(3) 462-470, 2011
장항배 Hang Bae Chang , 김흥국 Heung Gook Kim
DOI: JANT Vol.15(No.3) 462-470, 2011
Since, Davis(1991) has proposed the TAM(Technology Acceptance Model) through a literature review of informatization promotion, which insists that a user conveniency is judged by the degree of effectiveness caused by IT, the advancement of IT such as the Internet, e-mail, electronic data exchange, and groupware have brought into various changes in ordinary corporations and public institutions. However, with the right function, the advancement of IT has provided various benefits including additional reverse functions. Based on an integrated environment of business process, unauthorized user could access to information and a management of information becomes more difficult than before due to informatization of critical information. Furthermore, external hacking or information leakage by insider becomes easier owing to advancement in communication technology. This study has tried to develop a specified management procedure and implementation method for confidential documents.
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