• Proceedings of KOSOMES biannual meeting
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• 2003.05a
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• pp.135-139
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• 2003

This paper describes on the development of Passive-type Radar Reflector for Fisheries (PRR-F) based on the newly revised 2000 SOLAS regulations. The purpose of PRR-F is to provide it as the protection devices of a fishing net and a fishing field. The PRR-F is composed of corner cluster bundle of light galvanized iron, and it is inserted into floating styrofoam. Performance tests for the PRR-F are carried out in an anechoic chamber. The test results show that the reflected radar signal from PRR-F is large enough for the purpose.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.8 s.179
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• pp.2000-2006
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• 2000

The enhancement of service life of damaged or cracked structures is currently major issue to the researchers and engineers. In order to improve the life of cracked aging aircraft structures, the repair technique which uses adhesively bonded boron/epoxy composite patches is being widely considered as a cost-effective and reliable method. This paper is to study the performance of the bonded composite patch repair of a plate containing an inclined central through-crack. A 3-dimensional finite element method having three layers to the cracked plate, composite patch and adhesive layer, is used to compute the stress intensity factor. In this paper, the reduction of stress intensity factors near the crack-tip are determined to evaluate the effects of various non-dimensional design parameter including composite patch thickness, and material properties of the composite patch and thickness of the adhesive layer, materials of patch etc., and the crack length, Finally, The problem of how to optimize the patch geometric configurations has been discussed.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.12A
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• pp.1992-2001
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• 1999

We address the frequency management in the IMT-2000 CDMA system. The system characteristics such as multiple classes of services, multiple kinds of channels with different bandwidths, overlaid cell structure, etc. are examined to make way for the problem definition. The problem is formulated as a constrained optimization model, the objective of which is to consume as narrow bandwidth as possible while satisfying various multimedia demands with required QOSs. A solution algorithm is developed which generates two sets of optimal decisions: 1) which combination of service classes to assign to each cell, 2) which set of frequency channels of varying bandwidths to allocate to each cell. The effectiveness of the proposed deployment policy is demonstrated via computational experiments.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.46 no.3
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• pp.37-43
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• 2009

The new still image compression standard JPEG2000 is consisted of DWT and EBCOT. In this paper, proposed and designed new algorithm in efficient EBCOT. BPC based on the contort. Proposed BPC Algorithm is forecasted coding pass using Sigstage, column, mpass value. BAC design apply 4-pipeline stage. EBCOT designed using Verilog HDL. Verification and Synthesis using Xillinx FPGA technology.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.7C
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• pp.671-680
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• 2009

The diagnostic medical images(CT, MRI) in PACS require large storage and long transmission time. A simple and cheap way of overcoming these limitations is to increase the compression ratio. However, this requires a clinical validation for accurate diagnostic applications. The aim of this paper is to improve the compression efficiency of lossless JPEG2000 for diagnostic CT images by performing a visual-Iossless threshold filtering in high frequency subband. A proposed method, based on 5/3 reversible DWT, provides different subband-threshold values according to the compression ratio and gives the high subjective quality to reconstructed diagnostic CT images.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.5
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• pp.444-449
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• 2003

In this paper, a PCB(Printed Circuit Board) antenna for IMT-2000 is designed and analyzed. The antenna has a helical structure with via-holes and lines on FR-4($\varepsilon$$\sub$${\gamma}$/=4.6 ) PCB, and the type of feeding is GCPW(Grounded Co-Planar Waveguide). Using HFSS of Ansoft, the antenna was designed and the measured results of frequency and radiation characteristic,3 with VSWR<2.0 are satisfied within operating frequency band of 1.920∼2.170 GHz. And it has resonating frequency of 2.045 GHz and a bandwidth of 321 MHz. The radiation gain of the antenna was measured to be -1 dBi.

• Korean Institute of Interior Design Journal
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• v.20 no.1
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• pp.61-70
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• 2011

Based on the trend of architectural lighting of residential building, this study is to examine architectural lighting for residential buildings, and deduce the value and significance of architectural lighting by analyzing architectural lighting and characteristics of residential building through the analysis of works according to the types of works and by analyzing discourse relating to works of architectural lighting of residential building. First, architectural lighting for residential buildings can be categorized according to continuity and extensibility, lighting method and lighting factor. Second, architectural lighting of residential building has come into play since 2000 due to diversified activities at home. Third, architectural lighting had been introduced for living room and used in the form of structure or foundation up until early 2000s, but since mid 2000s, it has been used in intellectual and abstract form using various shapes, finishing material or objects. Fourth characteristic is a space of changing functions overcoming limited space, suggesting an alternative space, and using finishing material and object.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.8
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• pp.1755-1759
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• 2004

Digital watermarking technology is one of method of protecting property from the illegal reproduction of digital data. This technology inserts the specific data in a certain file to identify the property, that is an author and rights, not for human to be seen and heard. In this paper, the watermarking technology which inserts a RGB color watermark in a JPEG2000 color image using the visual characteristics of wavelet coefficient was proposed. After applying various attack at a watermarked image according to proposed technology, the likeness between the original image, the watermark and the extracted watermark was measured and investigated. As a result, the PSNR value of image was varied depending on perceptual parameter, but we can obtain 32dB as a whole.

• Nuclear Engineering and Technology
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• v.41 no.8
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• pp.1005-1014
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• 2009

The Dual Unit Optimizer 2000 MWe (DUO2000) is put forward as a new design concept for large power nuclear plants to cope with economic and safety challenges facing the $21^{st}$ century green and sustainable energy industry. DUO2000 is home to two nuclear steam supply systems (NSSSs) of the Optimized Power Reactor 1000 MWe (OPR1000)-like pressurized water reactor (PWR) in single containment so as to double the capacity of the plant. The idea behind DUO may as well be extended to combining any number of NSSSs of PWRs or pressurized heavy water reactors (PHWRs), or even boiling water reactors (BWRs). Once proven in water reactors, the technology may even be expanded to gas cooled, liquid metal cooled, and molten salt cooled reactors. With its in-vessel retention external reactor vessel cooling (IVR-ERVC) as severe accident management strategy, DUO can not only put the single most querulous PWR safety issue to an end, but also pave the way to very promising large power capacity while dispensing with the huge redesigning cost for Generation III+ nuclear systems. Five prototypes are presented for the DUO2000, and their respective advantages and drawbacks are considered. The strengths include, but are not necessarily limited to, reducing the cost of construction by decreasing the number of containment buildings from two to one, minimizing the cost of NSSS and control systems by sharing between the dual units, and lessening the maintenance cost by uniting the NSSS, just to name the few. The latent threats are discussed as well.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.11
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• pp.97-104
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• 2004

This paper proposes an efficient VLSI architecture of 9-7/5-3 Lifting DWT filters that is used by lossy or lossless compression of JPEG2000. The proposed architecture uses only internal line memories to compute Lifting-DWT operations and its PE(Processing Element) has critical path with 1 multiplier and 1 adder. To reduce the number of PE, we make the vertical filter that is responsible for the column operations of the first level perform both the row and column operations of the second and following levels. As a result, the architecture has smaller hardware cost compared to that of other architectures. It was modeled in RTL level using VHDL and implemented on Altera APEX 20K FPGA.