• Title/Summary/Keyword: 디지털기법

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Social Annotation and Navigation Support for Electronic Textbooks (전자책 환경을 위한 사회적 어노테이션 및 탐색 지원 기법)

  • Kim, Jae-Kyung;Sohn, Won-Sung
    • Journal of Korea Multimedia Society
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    • v.12 no.10
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    • pp.1486-1498
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    • 2009
  • Modem efforts on digitizing electronic books focus on preserving authentic image representation of the original sources. Unlike the text-based format, it is difficult to recognize the information in the image, so the new format requires new tools to help users to access, process, and make sense of digital information. This paper presents an approach which assists users of these image sources by giving them a combination of annotation and social navigation support. Especially in the education domain, the proposed technique improves the usability of online education system. This approach is currently fully implemented and under evaluation in a classroom study.

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Constructing the Switching Function using Partition Techniques (분할 기법을 이용한 스위칭함수 구성)

  • Park, Chun-Myoung
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2011.10a
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    • pp.793-794
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    • 2011
  • This paper presents a method of the circuit design of the multiple-valued digital logic switching functions based on the modular techniques. Fisr of all, we introduce the necessity, background and concepts of the modular design techniques for the digital logic systems. Next, we discuss the definitions that are used in this paper. For the purpose of the circuit design for the multiple-valued digital logic switching functions, we discuss the extraction of the partition functions. Also we describe the construction method of the building block, that is called the modules, based on each partition functions. And we apply the proposed method to the example, we compare the results with the results of the earlier methods. In result, we decrease the control functions, it means that we obtain the effective cost in the digital logic design for any other earlier methods. In the future research, we require the universal module that traet more partition functions and more compact module.

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A Study on the Fingerprinting scheme without Trusted Third Party (신뢰기관 비참여의 핑커프린팅 기법에 관한 연구)

  • Yong, Seung-Lim
    • Journal of the Korea Society of Computer and Information
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    • v.14 no.7
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    • pp.81-88
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    • 2009
  • Fingerprinting scheme is a technique which supports the copyright protection to track redistributors of digital content using cryptographic techniques. These schemes enable the original merchant to identify the original buyer of the digital data by embedding fingerprints into digital contents. Asymmetric property of fingerprinting schemes is important to keep the buyer's privacy. In this paper, we propose a symmetric encryption based fingerprinting protocol without trusted third party. Our scheme enables the reduction of computational costs for the encryption using symmetric key encryption scheme. Since a trusted third party doesn't take part in making the fingerprint of each buyer, the protocol doesn't need to control the trusted third party and it is more secure against collusion attack.

디지털 서명 인증관리센터의 인증서버 구현

  • 송영부
    • Proceedings of the CALSEC Conference
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    • 1999.11a
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    • pp.226-231
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    • 1999
  • ■ 디지털 콘텐츠(Digital Contents)란\ulcorner -컴퓨터상에서 Digital(0 또는 1)로 존재 하는 무형 의 데이터(예, 멀티미디어, 영상, MP3, S/W) ■ 디지털 콘텐츠 보호의 필요성 -불법복제 파일의 유통방지 -디지털 저작권 보호, 지적재산권 보호 -사용자 인증, 기밀성, 무결성 ■ 암호학적 방법 -공개키기반구조(PKI), 인증구조(X.509) -전자서명기법 (중략)

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Iterative Unsharp Mask Filter for Digital Auto-Focusing (디지털 자동초점을 위한 반복적 Unsharp Mask 필터)

  • Shin, Jeong-Ho
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.47 no.5
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    • pp.145-152
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    • 2010
  • This paper presents a digital auto-focusing algorithm using iterative unsharp mask filter. The proposed digital auto-focusing algorithm has the advantage of low computational complexity because it uses a simple filter instead of calculating the point spread function for the estimation of image degradation. The proposed iterative algorithm can control the number of iterations for image restoration according to the objective and the subjective criterion. We show that the proposed algorithm is mathematically equivalent to the conventional image restoration. Finally, in order to evaluate the performance of the proposed algorithm, various experiments are performed so that the proposed algorithm can provide good results in the sense of subjective and objective views.

Selective Recovery of the SSD TRIM Command in Digital Forensics (디지털 포렌식 관점에서 SSD TRIM 명령의 선별적 복구)

  • Hwang, Hyun Ho;Park, Dong Joo
    • KIPS Transactions on Computer and Communication Systems
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    • v.4 no.9
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    • pp.307-314
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    • 2015
  • Recently, market trends of auxiliary storage device HDD and SSD are interchangeable. In the future, the SSD is expected to be used more popular than HDD as an auxiliary storage device. The TRIM command technique has been proposed and used effectively due to the development of the SSD. The TRIM command techniques can be used to solve the problem of Freezing SSD that operating system cooperates with the SSD. The TRIM command techniques are performed in the idle time of the internal SSD that are actually deleted when a user deletes the data. However, in the point of view of computer forensics, the digital crime is increasing year by year due to lack of data recovery. Thus, this rate of arrest is insufficient. In this paper, I propose a solution that selectively manages data to delete based on advantage of the stability and the write speed of the TRIM command. Through experiments, It is verified by measuring the performance of the traditional method and selected method.

Implemention of digital holographic optical memory system using hybrid coding and image compression method (Hybrid 코딩과 영상압축방법을 이용한 디지털 홀로그래픽 광메모리 시스템의 구현)

  • 최안식;백운식
    • Korean Journal of Optics and Photonics
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    • v.11 no.3
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    • pp.210-217
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    • 2000
  • 본 논문에서 높은 에러 정정 성능을 갖는 디지털 홀로그래픽 광메모리 시스템을 구현하였다. 에러 정정 성능을 높이기 위해서, 비트에러 정정 능력을 갖고 있는 Hamming(12, 8, 1)코드와 산발 및 연집에러 정정 능력이 뛰어난 Reed-Sokomon 코드로 구성된 hydrid 코딩기법을 채용하였다. 입력 데이터로는 Lena 영상 (256$\times$256bytes)을 책택하였으며, 영상압축기법(JPEG)을 도입하였다. Hybrid 코딩과 영상압축기법을 조합한 광메모리 시스템의 시험결과가 제시되었다.

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Particle Shape Evaluation of Aggregate using Digital Image Process (디지털 이미지 처리 기법을 이용한 골재입자의 형상 분류)

  • Hwang, Taik-Jean;Cho, Jae-Yoon;Lee, Kwan-Ho;Song, Young-Sun
    • Journal of the Korean Society of Hazard Mitigation
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    • v.9 no.4
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    • pp.53-59
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    • 2009
  • The purpose of this research is particle shape evaluation of granular soil and aggregate using Digital Image Process(DIP). DIP is very useful to measure the roughness and particle shape of aggregates. Couple of aggregates, like standard sand, two different crushed stones, and two different marine aggregates, have been employed. Shape factor of two different marine aggregates is ranged 0.35 to 0.54. Crushed stone I is that of 0.74 which is highly flat, but standard sand is elongated shape. Especially, two marine aggregate showed a big difference of width and length which meaned a long shape. There is any significant difference of elongation ratio and flakiness for each aggregate with different measuring system, like direct measurement of vernier calipers and DIP method. Within the limited test results, DIP is one of useful to get the particle shape of aggregate with limitation of measuring errors and to apply the particle distribution curve.

Construction of the Digital Logic Systems based on the Improved Automatic Theorem Proving Techniques over Finite Fields (개선된 자동정리증명 기법에 기초한 유한체상의 디지털논리시스템 구성)

  • Park, Chun-Myoung
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.10 no.10
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    • pp.1773-1778
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    • 2006
  • This paper propose the method of constructing the Digital Logic Systems based on the Improved Automatic Theorem Proving Techniques(IATP) over Finite Fields. The proposed method is as following. First, we discuss the background and the important mathematical properties for Finite Fields. Also, we discuss the concepts of the Automatic Theorem Proving Techniques(ATP) including the syntactic method and semantic method, and discuss the basic properties for the Alf. In this step, we define several definitions of the IAIP, Table Pseudo Function Tab and Equal. Next, we propose the T-gate as Building Block(BB) and describe the mathematical representation for the notation of T-gate. Then we discuss the important properties for the T-gate. Also, we propose the several relationships that are Identity relationship, Constant relationship, Tautology relationship and Mod R cyclic relationship. Then we propose Mod R negation gate and the manipulation of the don't care conditions. Finally, we propose the algorithm for the constructing the method of the digital logic systems over finite fields. The proposed method is more efficiency and regularity than my other earlier methods. Thet we prospect the future research and prospects.

The Undeniable Digital Multi-Signature Scheme based on Biometric Information (생체정보 기반의 부인봉쇄 디지털 다중서명 기법)

  • Yun, Sung-Hyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.8 no.3
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    • pp.549-555
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    • 2007
  • A digital signature scheme provides integrity of the document, authentication and non-repudiation of a signer. Usually the key for digital signature is stored in hard disk or removal disk storage. The drawback of this approach is that the signer can let the agent to sign instead of the signer by providing the key information. It can be abused in applications such as electronic election. In this paper, we propose the undeniable biometric digital multi-signature scheme suitable for applications where the signer should not make an agent sign instead of himself/herself. The undeniable multi-signature scheme requires many signers and only the designated user can confirm the authenticity of multi-signature. The proposed scheme satisfies undeniable property and it is secure against active attacks such as modification and denial of the multi-signature by signers. As the key is generated through the signer's fingerprint image, it's also secure against signing by an agent.

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