• Title/Summary/Keyword: Digital techniques

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System Resolution Recovery by Motion Blur Recovery Technique - Particuar Application to X-ray Computerized Tomography (이동 Blur 회복법을 이용한 분해능 향상-X-ray C.T.에의 응용)

  • 이수영;김홍석
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.17 no.3
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    • pp.26-35
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    • 1980
  • The degradation of image due to the finite size of sensing devices has been one of the problems in all digital imaging systems. The basic study on the improvement of the spatial resolution was carried out in both spatial and frequency domains by the resolution recovery techniques which have been used in optics. Here, the techniques were applied to CT (Computerized Tomography) system, and image with finer resolution was obtained by these techniques. The basic theory is described and the results of the simulation are shown.

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FPGA Implementation of LSB-Based Steganography

  • Vinh, Quang Do;Koo, Insoo
    • Journal of information and communication convergence engineering
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    • v.15 no.3
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    • pp.151-159
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    • 2017
  • Steganography, which is popular as an image processing technology, is the art of using digital images to hide a secret message in such a way that its existence can only be discovered by the sender and the intended receiver. This technique has the advantage of concealing secret information in a cover medium without drawing attention to it, unlike cryptography, which tries to convert data into something messy or meaningless. In this paper, we propose two efficient least significant bit (LSB)-based steganography techniques for designing an image-based steganography system on chip using hardware description language (HDL). The proposed techniques manipulate the LSB plane of the cover image to embed text inside it. The output of these algorithms is a stego-image which has the same quality as that of the original image. We also implement the proposed techniques using the Altera field programmable gate array (FPGA) and Quartus II design software.

The Implementation of Low Power Operating System Based on Energy Mesuremen

  • Heon, Jeong-Jae;Ik, Chae-Soo
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.138.6-138
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    • 2001
  • In recent years, as the battery-powered portable systems such as cellular phone, personal digital assistant (PDA) are widely used, power consumption comes to be a top-priority design concerns. Because those embedded systems become more and more complex than ever and they are operated under severe power and energy constrains, long battery lifetime with a limited energy is very critical. Even though there are various levels of energy optimization techniques, system level techniques are mainly focused on, for their stronger impact on power consumption of the overall system than traditional techniques : circuit level, switch level, architecture level, etc. In this technique, operating system (OS) plays the most important role in the system because it controls ...

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Development of a Simple Computer Vision System (컴퓨터 시각 장치의 개발)

  • 박동철;석민수
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.20 no.1
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    • pp.1-6
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    • 1983
  • To give the recognition capability of task objects by computer vision to a sensor-based robot system, an image digitizer and some basic software techniques were developed and repofted here. The image digitizer was developed with the CROMEMCO SYSTEM III microcomputer anti C.C.T.V. camera to convert the analog valued scene into digitized image which could be pro-cessed by a digital computer. Basic software techniques for the computer vision system were aimed at the recognition of 3-dimensional objects. Experiments with these techniques were carried out using the image of a cubicle which could be considered as typical simple 3-dimensional object.

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Comparisons of Various DEM Interpolation Techniques

  • Kim, Tae-Jung
    • Proceedings of the KSRS Conference
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    • 1998.09a
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    • pp.163-168
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    • 1998
  • Extracting a Digital Elevation Model (DEM) from spaceborne imagery is important for cartographic applications of remote sensing data. The procedure for such DEM generation can be divided into stereo matching, sensor modelling and DEM interpolation. Among these, DEM interpolation contributes significantly to the completeness and accuracy of a DEM and, yet, this technique is often considered "trivial". However, na\ulcornere DEM interpolation may result in a less accurate and sometimes meaningless DEM. This paper reports the performance analysis of various DEM interpolation techniques. Using a manually derived DEM as reference, a number of sample points were created randomly. Different interpolation techniques were applied to the sample points to generate DEMs. The performance of interpolation was assessed by the accuracy of such DEMs. The results showed that kriging gave the best results at all times whereas nearest neighborhood interpolation provided a fast solution with moderate accuracy when sample points were large enough.

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Research of the EMI Test Methods for a Surveillance Radar Subsystem Against the Intermodulation and Undesired Signals (상호 변조 및 불요 신호에 대한 탐색레이더 부 체계의 EMI 시험 기법)

  • Lee, Jin-Ho
    • Journal of the Korea Institute of Military Science and Technology
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    • v.10 no.2
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    • pp.84-89
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    • 2007
  • MIL-STD-461E, EMI military standard for the equipment and subsystems, requires reception characteristic tests to verify the susceptibility of a receiver against the jntermodulation and spurious signals. Because the CS103 and CS104 of MIL-STD-461E show the test configuration of the equipment unit like a traditional receiver, it is possible to verify the susceptibility only for the reception signal through analog filters. However, at present when software programming techniques make a progress, the CS103 and CS104 tests need to evaluate the reception signal of the subsystem which includes both the digital filtering effects and analog filter characteristics. These test and evaluation techniques applied to a surveillance radar subsystem. This paper researched the EMI test methods in order to confirm feasibility of these test and evaluation techniques. Also the test results are compared and analyzed.

Effective Techniques for Diagnosis and Test of Hard-to-Detect Faults in Analog Circuits (아날로그 회로의 난검출 고장을 위한 효과적인 진단 및 테스트 기법)

  • Lee, Jae-Min
    • IEMEK Journal of Embedded Systems and Applications
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    • v.4 no.1
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    • pp.23-28
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    • 2009
  • Testing of analog(and mixed-signal) circuits has been a difficult task for test engineers and effective test techniques to solve these problems are required. This paper develops a new technique which increases fault detection and diagnosis rates for analog circuits by using extended MTSS (Modified Time Slot Specification) technique based on MTSS proposed by the author. High performance current sensors with digital outputs are used as core components for these techniques. A fault diagnosis structure with minimal hardware overhead in ATE is also described.

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A Study on the Fusion of DEM Using Optical and SAR Imagery

  • Yeu, Bock-Mo;Hong, Jae-Min;Jin, Kyeong-Hyeok;Yoon, Chang-Rak
    • Proceedings of the KSRS Conference
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    • 2002.10a
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    • pp.407-407
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    • 2002
  • The most widespread techniques for DEM generation are stereoscopy for optical sensor images and interfereometry for SAR images. These techniques suffer from certain sensor and processing limitations, which can be overcome by the synergetic use of both sensors and DEMs respectively. In this paper, different strategies for fusing SAR and optical data are combined to derive high quality DEM products. The filtering techniques, which take advantage of the complementary properties of SAR and stereo optical DEMs, will be applied for the fusion process. By taking advantage of the fact that errors of the DEMs are of different nature using the filtering technique, affected part are filtered and replaced by those of the counterpart and is tested with two sets of SPOT and ERS DEM, resulting in a remarkable improvement in DEM. for the analysis of results, the reference DEM is generated from digital base map(1:5000).

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Technology Trends for Motion Synthesis and Control of 3D Character

  • Choi, Jong-In
    • Journal of the Korea Society of Computer and Information
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    • v.24 no.4
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    • pp.19-26
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    • 2019
  • In this study, we study the development and control of motion of 3D character animation and discuss the development direction of technology. Character animation has been developed as a data-based method and a physics-based method. The animation generation technique based on the keyframe method has been made possible by the development of the hardware technology, and the motion capture device has been used. Various techniques for effectively editing the motion data have appeared. At the same time, animation techniques based on physics have emerged, which realistically generate the motion of the character by physically optimized numerical computation. Recently, animation techniques using machine learning have shown new possibilities for creating characters that can be controlled by the user in real time and are expected to be developed in the future.

Digital Forensics Ontology for Intelligent Crime Investigation System (지능형 범죄수사 시스템을 위한 범용 디지털포렌식 온톨로지)

  • Yun, Han-Kuk;Lee, Sang-Hoon
    • Journal of the Korea Society of Computer and Information
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    • v.19 no.12
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    • pp.161-169
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    • 2014
  • Digital forensics is the process of proving criminal charges by collecting and analyzing digital evidence which is related to the crime in question. Most digital forensic research is focused on digital forensic techniques themselves or cyber crime. In this paper, we designed a digital forensics-criminal investigation linked model in order to effectively apply digital forensics to various types of criminal investigations. Digital forensic ontology was developed based on this model. For more effective application of digital forensics to criminal investigation we derived specific application fields. The ontology has legality rules and adequacy rules, so it can support investigative decision-making. The ontology can be developed into an intelligent criminal investigation system.