• Title/Summary/Keyword: Cot

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Secure Oblivious Transfer Protocol-based Digital Fingerprinting Against Conspiracy Attack (공모 공격에 안전한 불확정 전송 프로토콜 기반의 디지털 핑거프린팅 기법)

  • 최재귀;박지환;김태석
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.14 no.3
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    • pp.145-153
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    • 2004
  • Digital fingerprinting schemes are cryptographic methods that a seller can identify a traitor who illegally redistributed digital contents by embedding it into buyer's information. Recently, Josep Domingo-Ferrer suggested an anonymous digital fingerprinting scheme based on committed oblivious transfer protocol. It is significant in the sense that it is completely specified from a computation point of view and is thus readily implementable. But this scheme has the serious problem that it cannot provide the security of buyers. In this paper, we first show how to break the existing committed oblivious transfer-based fingerprinting schemes and then suggest secure fingerprinting scheme by introducing oblivious transfer protocol with two-lock cryptosystem based on discrete logarithm. All computations are performed efficiently and the security degree is strengthened in our proposal.

Design of a Cost-Effective Hybrid-Type PBEx Providing a High Power Budget in an Asymmetric 10G-EPON

  • Kim, Kwangok;Lee, Sangsoo;Lee, Jonghyun;Jang, Younseon
    • ETRI Journal
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    • v.34 no.6
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    • pp.838-846
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    • 2012
  • This paper proposes a cost-effective hybrid-type power budget extender (PBEx) that can provide a high power budget of over 45 dB in an asymmetric 10-Gb/s Ethernet passive optical network (10/1G-EPON). The hybrid-type 10/1G-EPON PBEx comprises a central office terminal (COT) and remote terminal (RT) module supporting four channels and uses a coarse wavelength division multiplexing (CWDM) technology between the COT and RT for a reduction of fiber cost and efficient access network design. The proposed 10/1G-EPON PBEx can provide over a 40-km reach and 128-way split per CWDM wavelength with no modification of a legacy 10/1G-EPON system and can satisfy the error-free service in $10^{10}$ packet transmission.

Understanding and Application of MILD combustion (마일드연소의 이해와 응용)

  • Kim, Nam Il
    • 한국연소학회:학술대회논문집
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    • 2014.11a
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    • pp.281-282
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    • 2014
  • Recently, studies on Mild combustion have grown in many combustion application fields in the international combustion society. Compared with international activities in this field, domestic study in Korea has not been activated yet. This brief review aims to explain some essences of fundamental physics of Mild combustion and to introduce some recent application techniques of them. Fundamental physics of Mild combustion has been usually broken down into three aspects [1]; physical, thermodynamic, and chemical aspects. A major portion of Mild combustion physics is related to HiTAC (High Temperature Air Combustion) or HiCOT (High Temperature Combustion Technology). Although definition of Mild combustion is easily accepted among combustion engineers, combustion control in Mild combustion may be difficult without understanding essential physics of it. To encourage the research in this field, some representative cases will be introduced, and related essential techniques will be explained.

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Design Principles and Validation of a Human-sized Quadruped Robot Leg for High Energy Efficiency (에너지 효율적인 인간 크기 4족 보행 로봇의 설계와 검증)

  • Yeom, Hoyeon;Ba, Dang Xuan;Bae, Joonbum
    • The Journal of Korea Robotics Society
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    • v.13 no.2
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    • pp.86-91
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    • 2018
  • This paper presents about design efforts of a human-sized quadruped robot leg for high energy efficiency, and verifications. One of the representative index of the energy efficiency is the Cost of Transport (COT), but increased in the energy or work done is not calculated in COT. In this reason, the input to the output energy efficiency should be also considered as a very important term. By designing the robot with customized motor housing, small rotational inertia, and low gear ratio to reduce friction, high energy efficiency was achieved. Squatting motion of one leg was performed and simulation results were compared to the experimental results for validation. The developed 50 kg robot can lift the weight up to 200 kg, and during squatting, it showed high energy efficiency. The robot showed 71% input to output energy efficiency in positive work. Peak current during squatting only appears to be 0.3 A.

Enhancing Software Value and Quality in COTS-based Requirements Engineering (소프트웨어의 가치와 품질향상을 위한 COTS 기반의 요구공학방법론)

  • Han, Youngsub;Kim, Neunghoe;Lee, Donghyun;In, Hoh Peter
    • Proceedings of the Korea Information Processing Society Conference
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    • 2009.11a
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    • pp.853-854
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    • 2009
  • 고객가치에 기반을 두지 않은 소프트웨어는 블루오션을 창출할 수 없고, 기존 시장에서 우위를 점유할 수 없으므로 최근에는 고객가치와 품질 향상에 초점을 맞춰 소프트웨어 개발이 이루어지고 있다. 또한 시장에서 우위를 차지하기 위한 중요한 요소 중 하나가 비용인데, COTS 기반의 개발방법은 시장출하 시간의 단축과 비용절감의 효과가 있어 관심이 증가하는 추세이다. 본 논문에서는 고객가치를 창출하고 소프트웨어 품질을 향상시키기 위해 고객가치와 COTS의 품질속성을 고려하여 COTS를 선택하는 요구공학방법론을 제시하였다.