• Title/Summary/Keyword: Public key distribution

검색결과 186건 처리시간 0.025초

전자상거래 지불시스템을 위한 보안 프로토콜 설계 (The Design of the Security Protocol for Electronic Commerce Payment System)

  • 이상덕;한승조
    • 한국항행학회논문지
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    • 제11권1호
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    • pp.112-117
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    • 2007
  • 현대 사회는 인터넷의 급속한 보급과 발전으로 사회활동 전반에 걸친 변화를 주도하고 있으며, 새로운 형태의 상거래인 인터넷을 이용한 전자상거래(Electronic Commerce)가 확산 발전되고 있다. 본 논문에서는 공용 키 (PKI)에 기초를 두는 네트워크형 전자지불 프로토콜을 제안하고자 한다. 제안된 프로토콜은 컨텐츠 거래를 위해 개발된 NetBill 시스템의 익명성을 보장하지 못했던 단점을 보완하였다. 또한 온라인 상에서 제공된 디지털 콘텐츠에 대해 인증번호를 부여함으로써 무단 복제를 방지하고 최대한 안전성이 확보되도록 하였다.

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구매자-판매자 워터마킹 프로토콜상에서 DCT 기반의 방향성 적응 워터마킹 (A Direction-Adaptive Watermarking Technique Based on 2DCT in the Buyer-Seller Watermarking Protocol)

  • 성택영;권기창;이석환;권기룡;우종호
    • 한국멀티미디어학회논문지
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    • 제17권7호
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    • pp.778-786
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    • 2014
  • Buyer-seller watermarking protocol is one of the copyright protection techniques which combine a cryptographic protocol used in electronic commerce with a digital wetermarking scheme aiming at proving the ownership of multimedia contents and preventing the illegal reproduction and redistribution of digital contents. In this paper, it is proposed a new watermarking scheme in an encrypted domain in an image that is based on the block-DCT framework. In order to implement watermarking scheme in a public-key cryptosystem, it is divided that frequency coefficients exist as real number into integer and decimal layer. And the decimal layer is modified integer type through integral-processing. Also, for robustness and invisibility required in watermarking scheme, it is designed a direction-adaptive watermarking scheme based on locally edge-properties of each block in an image through analyzing distribution property of the frequency coefficients in a block using JND threshold.

Design and Analysis of Efficient Parallel Hardware Prime Generators

  • Kim, Dong Kyue;Choi, Piljoo;Lee, Mun-Kyu;Park, Heejin
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제16권5호
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    • pp.564-581
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    • 2016
  • We present an efficient hardware prime generator that generates a prime p by combining trial division and Fermat test in parallel. Since the execution time of this parallel combination is greatly influenced by the number k of the smallest odd primes used in the trial division, it is important to determine the optimal k to create the fastest parallel combination. We present probabilistic analysis to determine the optimal k and to estimate the expected running time for the parallel combination. Our analysis is conducted in two stages. First, we roughly narrow the range of optimal k by using the expected values for the random variables used in the analysis. Second, we precisely determine the optimal k by using the exact probability distribution of the random variables. Our experiments show that the optimal k and the expected running time determined by our analysis are precise and accurate. Furthermore, we generalize our analysis and propose a guideline for a designer of a hardware prime generator to determine the optimal k by simply calculating the ratio of M to D, where M and D are the measured running times of a modular multiplication and an integer division, respectively.

공사계약일반조건의 위험요인 감소방안 (Risk Mitigation Methodology of the General Conditions of Contract)

  • 윤철성;권순오;김선규
    • 한국건설관리학회논문집
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    • 제6권5호
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    • pp.177-185
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    • 2005
  • 건설공사의 불확실성은 빈번히 클레임에 노출된다. 대부분의 경우 이러한 클레임에 대한 기본적인 해석은 공사계약서를 기준으로 하게 된다. 이러한 계약서 작성시의 문제는 발주자나 시공자가 부담하여야 하는 계약적 위험(risk)이 어떻게 규정되어 있어야 합리적인 수준인가를 판단하는 것인데 이러한 판단을 위해서는 FIDIC 계약조건과 같이 국제적으로 합리성을 인정받는 표준계약조건을 참고하는 것이 합리적이라 하겠다. 이에 본 연구는 FIDIC 계약조건을 기준으로 국내 공공공사에서 일반적으로 사용하는 공사계약일반조건에 내재되어 있는 불공정, 불합리 조항을 분석하여 세계적 수준에 맞는 공사계약조건을 제시하고자 위험관리의 관점에서 공사 계약조건을 분석하고, 여기서 도출되는 위험요인을 검증하며, 이에 대한 대응방안을 모색함으로써 공사계약일반조건의 위험요인 감소방안을 제시하고자 한다.

DCT and Homomorphic Encryption based Watermarking Scheme in Buyer-seller Watermarking Protocol

  • Seong, Teak-Young;Kwon, Ki-Chang;Lee, Suk-Hwan;Moon, Kwang-Seok;Kwon, Ki-Ryong
    • 한국멀티미디어학회논문지
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    • 제17권12호
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    • pp.1402-1411
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    • 2014
  • Buyer-seller watermarking protocol is defined as the practice of imperceptible altering a digital content to embed a message using watermarking in the encryption domain. This protocol is acknowledged as one kind of copyright protection techniques in electronic commerce. Buyer-seller watermarking protocol is fundamentally based on public-key cryptosystem that is operating using the algebraic property of an integer. However, in general usage, digital contents which are handled in watermarking scheme mostly exist as real numbers in frequency domain through DCT, DFT, DWT, etc. Therefore, in order to use the watermarking scheme in a cryptographic protocol, digital contents that exist as real number must be transformed into integer type through preprocessing beforehand. In this paper, we presented a new watermarking scheme in an encrypted domain in an image that is based on the block-DCT framework and homomorphic encryption method for buyer-seller watermarking protocol. We applied integral-processing in order to modify the decimal layer. And we designed a direction-adaptive watermarking scheme by analyzing distribution property of the frequency coefficients in a block using JND threshold. From the experimental results, the proposed scheme was confirmed to have a good robustness and invisibility.

지역갈등과 지역정책 (Regionalism and Regional Policy)

  • 홍성웅
    • 지역연구
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    • 제6권1호
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    • pp.1-10
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    • 1990
  • Regionalism has become a liability in Korea, hampering national harmony and political stability. The regionalism finds its roots in several centuries back in history. The traditional regionalism was based on the provincial differences in cultural and social characteristics, and behavioral mannerism. Therefore, the traditional regionalism should be regarded as benign and common as in many other countries in the world. The modern version of Korean regionalism seems to be founded on the "discriminatory" treatments of Honam provinces in economic policy and the resultant regional economic disparity during the last three decades. Many believe that such "discriminatory" policy had been enforced during the period of the "third" and "fourth" republics under the influence of the key government officials and presidents form the Southeastern provinces. Since the early 80s, many public investment projects have found its home in the Honam region with the consideration of regional balance and more equitable distribution. This paper attempts to elucidate on various causes of regional disparity amplified during the period of industrialization, and also presents the economic indices which demonstrate the impacts of the policy in narrowing the economic disparity among the regions in recent years. The paper also clarifies the limits of regional economic policy in achieving regional. balance and consequently social integrity. The last part of the paper attempts to clarify the effective domain of regional policy and the new direction of regionalism.cy and the new direction of regionalism.

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태평양 원양어업의 효율제고를 위한 원격해양자료 활용기술 연구 (A Study on the Utilization of Satellite Ocean Data for Efficient Fisheries in the Pacific Ocean)

  • 강현선;송무석;홍기용
    • 한국해양환경ㆍ에너지학회지
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    • 제5권4호
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    • pp.19-26
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    • 2002
  • 본 논문은 태평양 원양어업의 효율을 제고하기 위해 필수적으로 요구되는 정보인 해양의 표층수온분포, 수심별 수온분포, 흐리고 플랑크톤의 분포를 원양어선에 실시간으로 제공하는 시스템 구축을 목적으로 하는 기초연구의 보고이다. 위성 및 해양부이에 의해 취득되고 있는 다양한 공개된 자료를 분석하였고, 이들의 어업관점에서의 효과적인 조합과 현장에서의 활용도 제고를 위한 방안을 제시하였다. NOAA의 고해상도 적외선 위성자료의 표면수온분포 자료, 태평양 해역 적노부분을 중심으로 배열된 TAO/TRITON 부이와 광범위한 지역에 분포한 ARGOS 표류부이의 수심별 수온자료, 그리고 MODIS 위성에 의한 해색자료를 활용한 정보가공의 기본형태를 제안하고 예를 보였다.

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The Impact of Supertall Density on City Systems

  • Price, Bill;Bickerdyke, Andrew;Borchers, Meike;Gabbitas, Tim;Hailey, Lee
    • 국제초고층학회논문집
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    • 제6권4호
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    • pp.327-332
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    • 2017
  • This paper discusses several topics associated with the densification caused by supertall buildings and their impact on city systems. The paper covers five key areas where a supertall tower creates a concentration of needs and effects. First, the paper comments on population shifts towards the city and how they affect carbon footprint, utilities infrastructure and transport. The effect of single- and mixed-use towers is discussed in the context of population density. The second section brings the issues of transit, accessibility and master planning into focus. The use and criticality of public transport, cycling and walking is described. Servicing and deliveries using freight consolidation and shared systems is also discussed along with their contribution to the culture of sustainable travel. In the third section the paper reflects on supertall buildings' below-ground utilities and drainage provision, particularly the challenges faced in established city infrastructures. The utilities issues associated with supertall concentration (in land-use terms) compared to equivalent low-rise distribution is also commented on in the context of surface water runoff. In the fourth section, the topic of supertall sustainability is discussed and how city systems need to respond to create desirable and affordable space for occupiers. The changing need for vertical communities, 'stacked neighbourhoods' and the notion of a micro-city is described. Finally, the paper considers the energy consumption and resilience of supertall buildings in the context of basic geometry, façade design, climate and mixed-use benefits as they impact city systems.

공연장 무대공간의 구성과 전환시스템의 특성에 관한 연구 (A Study on the Characteristic of Space Composition & Scenery System in the Stage)

  • 류천혁;최성주;황미영
    • 한국실내디자인학회논문집
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    • 제15권1호
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    • pp.121-130
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    • 2006
  • The key role of performance facilities is to provide the stage shape and stage system suitable for the purpose and the property of public performance. The purpose of this study is to draw comparison analysis about the stage construction and stage machine system of the specialty theater or the multiple purpose performance facilities. The progress of the research is as followings. 1. Investigation into literature and catching on physical composition in the performing facilities, 2. Analysis of the stage organization, items of performance, construction form of stage machine systems, conversion system of the analysis samples, 3. A suggestion of the standard model of stage by each scales, through the such continuous analysis. And it was founded that the relation of stage composition, production type, stage system and distribution, and also the basic data between each elements. On the basis of the results, this study proposes the data and the application methods in domestic performance space when we are setting up the plan of performance facilities.

Good Corporate Governance: A Case Study of Family Business in Indonesia

  • RUSTAM, Akie Rusaktiva;NARSA, I Made
    • The Journal of Asian Finance, Economics and Business
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    • 제8권5호
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    • pp.69-79
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    • 2021
  • Good Corporate Governance (GCG) has been implemented by companies, especially companies that have gone public. However, many local companies still have not applied the principles of GCG. This study examines the implementation of the CG concept which is not fully implemented in family businesses in Indonesia. Besides, this research also aims to find out the role of the Internal Audit function in enhancing GCG practices. This research is a qualitative study that uses in-depth interviews, observation, and data triangulation, to gather evidence from exploratory case studies conducted in three family business firms. The results of this study found that CG is essential for the successful run of family businesses. After analyzing the data, we developed a new theory called Islamic Integrity Governance. The Internal Auditor plays a key role in improving GCG and a vibrant and agile internal audit function can be an indispensable resource supporting sound corporate governance. The internal auditor provides objective assurance and insight on the effectiveness and efficiency of risk management, internal control, and governance processes. Therefore, the Internal Auditor is an important pillar for effective and efficient GCG implementation. This theory concludes several concepts such as THTCL (Trustworthy, Honest, Transparent, Creative, Loyal). Internal auditors are needed because the concept of control is useful for improving GCG in business.