• 제목/요약/키워드: Private key

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Robust Digital Video Watermarking Algorithm Using Dual Watermarks in Block DCT Domain

  • Kim, Byung-Ju;Lee, Suk-Hwan;Kwon, Ki-Ryong;Ahn, Sang-Ho;Kim, Tai-Suk;Lee, Kuhn-Il
    • 한국멀티미디어학회논문지
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    • 제7권6호
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    • pp.791-797
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    • 2004
  • We proposed a novel digital video watermarking that embeds dual watermarks in the block DCT domain to solve the deadlock problem. Daul watermarks are composed of private watermarks and robust blind watermarks. Firstly, private watermarks are embedded into the lowest AC coefficients of the P or B-frames in accordance with the motion direction gained from a previous frame. Secondly, blind watermarks that have the robustness are inserted into the DC coefficients of the I-frames using a private key made from temporal I-frame motion information. Thus, when a deadlock situation occurs, the proposed algorithm can efficiently solve the problem. Experimental results confirmed that the proposed algorithm can produce good subjective and objective results for MPEG coding with a variety of bit rates. Furthermore, the proposed watermarking algorithm can potentially be applied to broadcasting monitoring systems due to its simplicity and high robustness.

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상관도 검출기반의 비대칭 공개 키 워터마킹 (Asymmetric public-key watermarking based on correlation method)

  • 이덕;김종원;최종욱
    • 한국컴퓨터정보학회논문지
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    • 제10권3호
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    • pp.151-159
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    • 2005
  • 기존의 디지털 워터마킹 기술은 대부분 삽입과 검출에서 동일한 키를 사용하는 대칭키 방식이다. 이러한 대칭키 워터마킹 방식은 검출을 쉽게 할 수 있는 반면에 공격자에 의하여 검출기의 비밀 키 정보가 유출될 경우 삽입 정보가 제거되거나 변조되는 치명적인 공격을 받을 수 있다. 따라서 최근에는 삽입기에서 삽입한 비밀 정보를 검출기에서 공개 키를 이용하여 검출하는 비대칭 워터마킹(Asymmetric watermarking)방식이 차세대 워터마킹 기술로 주목을 받고 있다. 본 논문에서는 선형 연립방정식의 해집합을 이용하여 개인 키의 탐색 공간을 효과적으로 확장하였다. 또한 공개 키로부터 개인 키를 유출할 수 없도록 하기 위하여 공개 키의 생성은 안전한 선형변환 방식에 기초하였으며 높은 상관도 검출이 가능하도록 구성되었다. 실험결과 워터마크가 삽입된 영상에서 1비트의 정보 뿐만 아니라, 멀티 비트의 정보에 대한 공개 키 상관도 검출이 정확히 이루어짐을 확인할 수 있었으며 JPEG압축 후에도 높은 상관도 검출이 가능한 것으로 나타났다.

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중고령 가구의 재무구조와 성인자녀로 부터의 소득이전 (Analyzing Adult Children's Income Transfers to Parents According to Financial Structure)

  • 윤원아
    • 한국생활과학회지
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    • 제19권2호
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    • pp.361-374
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    • 2010
  • Using the first wave of the Korean Longitudinal Study of Ageing, this research examines the effect of elderly parent's financial structure on private income transfers from their adult children. The results show that low income elderly households are more likely to receive income transfers from their children. Generally, Korean elderly households were found to have very low liquidity in their asset structure, as the average household holds over 90% of their assets in real estate. However, it seems that the parents' potential income based on their real estate assets is unimportant in determining children's transfer decisions. Rather, the parents' labor income is found to be a key factor in children's income transfer decisions.

Watermarking Based on Complemented MLCA and 2D CAT

  • Li, Xiao-Wei;Yun, Jae-Sik;Cho, Sung-Jin;Kim, Seok-Tae
    • Journal of information and communication convergence engineering
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    • 제9권2호
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    • pp.212-216
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    • 2011
  • Digital watermarking has gained importance in recent years in copyright protection and multimedia. This paper proposes a secure and novel watermarking system based on complemented Maximum Length Cellular Automata (MLCA) and Two-Dimension Cellular Automata Transform (2D CAT). In this watermarking scheme, the original watermark is first encrypted by complemented MLCA with the private keys, and then the encrypted watermark is embedded into the CAT domain of the cover image, at last use the inverse CAT for the transformed image, the watermarked image is obtained. Experiment results show that this new method is more secure and provides robust performance against watermarking attacks.

의복불평행동에 관한 연구 -의복 불평행동의 분류법과 원인, 유형을 중심으로- (A Study on Clothing Complaining Behavior : Taxonomy Cause and Type)

  • 홍금희
    • 한국의류학회지
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    • 제23권1호
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    • pp.90-110
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    • 1999
  • Understanding consumer complaining behaviors plays a key role in post-purchase satisfaction customer retention and long-term customer relationships. This research was conducted to empirically investigate 1) the taxonomy of complaining behavior 2) causes and types of clothing complaining behavior according to sex. The subjects compoed of 250 male and 358 female consuemrs. Data were colleted through questionnaires employing the critical incident methodology. The findings indicated that clothing complaining behavior was fitted well into Singh(1998)'s three-factor model(i. e. voice/private / third-party complaining behaviors) these factors explained 53% of the total variances 75.1% of male and 65.2% of female group complained of poor instruental performance. The types of complaining behaviors were no action negative word-of-mouth to friends and associates n order. Most dissatisfied consumers didn't assert positive consumer's right. Marketer should increase the accessibility of their complaint receiving mechanisms to passive customers.

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민간투자유치를 통한 u-City 구축에 있어서 사전 타당성 분석의 핵심요인과 분석모델 (Key Factors and Analysis Models of the Preliminary Feasibility Study in u-City Construction by Attracting Private Investment)

  • 김명동;박광호
    • 산업경영시스템학회지
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    • 제35권3호
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    • pp.1-6
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    • 2012
  • This paper aims to suggest a validity analysis model that would be helpful for local governments considering u-City construction projects and a methodology for them to promote build-transfer-lease (BTL) u-City projects. This methodology mainly uses quantitative and qualitative analysis based on the Value For Money (VFM) designed by the Public and Private Infrastructure Investment Management Center (PIMAC) under the Korea Development Institute (KDI). BTL projects requires a large amount of capital and involves long-term investments. Therefore, multi-faceted validity analysis is required for the success of a project. This study will enumerate various factors to be considered in the pre-analysis of validity of BTL projects and suggest a methodology to verify them. A case study of a BTL project promoted by Ansan City assisted in designing this study in detail.

The current status of research and development in electrical engineering of Korea

  • 박상희
    • 전기의세계
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    • 제44권5호
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    • pp.39-41
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    • 1995
  • Korean government has created the organizations for the private research development, has increased the support in taxes and funds, and has promoted the simplification of administrative structure and the removal of unnecessary restriction for the settlement of the private enterprise-centered technical reformation system. The investment of the research and development of Korea was 2.17% of GNP and the number of researchers was 89,000 in 1992. Korean government will expand the investment of research and development by 3-4% of GNP until 1998 and reinforce the number of researchers by 140,000. For the timely supply of the technical information, which is expected to be a major industry base in the year 2000, Korean government has already started to invest and continuously increased key projects which are focused on the database architectures, information distribution systems, and organizations for the information dissemination.

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USN에서의 이동성을 위한 핸드오버 인증 프로토콜 (Handover Protocol for Mobility Support in Ubiquitous Sensor Network)

  • 니반제 브루스;김태용;이훈재
    • 한국컴퓨터정보학회:학술대회논문집
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    • 한국컴퓨터정보학회 2012년도 제46차 하계학술발표논문집 20권2호
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    • pp.203-206
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    • 2012
  • The System of communication with wireless devices is experiencing a huge growth. While traditional communication paradigms deal with fixed networks, mobility raises a new set of questions, techniques, and solutions. In order to realize service mobility, there is a need of protocol that can support mobility while nodes are communicating without any disruption of their connection status. This paper proposes a handover authentication protocol for mobility support. Careful considerations must be taken in priority to security issues since many unreliable public and private resources; both networks and devices are involved. The protocol is based on public key cryptography with Diffie-Hellman algorithm which provides security against both leakage-resilience of private keys on untrustworthy devices and forward secrecy.

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A CASE STUDY ON INVESTMENT EVALUATION OF A PRIVATE SECTOR PROJECT WITH GEOTECHNICAL RISKS

  • Yoshiki Onoi;Hiroyasu Ohtsu
    • 국제학술발표논문집
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    • The 1th International Conference on Construction Engineering and Project Management
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    • pp.824-829
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    • 2005
  • This paper focuses on construction cost volatility for the purpose of private sector investment by use of a financial model with key indices of IRR and DSCR (Debt Service Coverage Ratio). A case project, 1,000 MW pumped storage hydropower plant, has shown that its financial impacts by cost volatility of underground works are less measured than interest rates impacts by interest rate of loans. Probabilistic analysis of costs under geotechnical conditions has been made by Indicator Kriging method. And, in the modeling of interest rates, geometric Brownian motion has been applied. Both of these impacts are measured on the same financial model.

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PROBLEMS AND SOLUTION OF IDENTIFICATION AND APPROVAL OF PRIVATELY FINANCED INFRASTRUCTURE PROJECTS IN CHINA

  • Xiangrong Du;Tsunemi Watanabe
    • 국제학술발표논문집
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    • The 1th International Conference on Construction Engineering and Project Management
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    • pp.731-736
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    • 2005
  • The governmental attitude toward private investment and financing for infrastructure projects has changed from the initial prohibition to the current encouragement in China, which has been embodied in the legal documents and administrative process. However, the problem of identification, bidding, and approval procedure for privately financed infrastructure projects has been observed in policies and administrative measures promulgated by different or even the same government branches, which is prohibitive factors for smooth project implementation. After analysis of the identification, bidding, and approval process of infrastructure projects, the authors proposed a simplified and alternative procedure and clarified the key points of relevant project documents.

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