• 제목/요약/키워드: zero-knowledge

검색결과 147건 처리시간 0.025초

Understanding Switching Arcs and Dielectric Capability of a SF6 Self-Blast Interrupter

  • 이원호;김철수;이종철
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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    • pp.196.2-196.2
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    • 2016
  • The design and development procedures of SF6 gas circuit breakers are still largely based on trial and error through testing although the development costs go higher every year. The computation cannot cover the testing satisfactorily because all the real processes arc not taken into account. But the knowledge of the arc behavior and the prediction of thermal plasmas inside SF6 interrupters by numerical simulations are more useful than those by experiments due to the difficulties to obtain physical quantities experimentally and the reduction of computational costs in recent years. In this paper, in order to get further information into the interruption process of a SF6 self-blast interrupter, which is based on the combination of thermal expansion and arc rotation, gas flow simulations with a CFD-arc modeling are performed during the whole switching process such as high-current period, pre-current zero period, and current-zero period. Through the complete work, the temperature of residual arcs as well as the breakdown index after current zero should be a good criterion to predict the dielectric capability of interrupters.

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중학생을 위한 제로에너지 주택디자인 STEAM 교육프로그램 개발 연구 (A Study on the STEAM Program Development of Zero Energy House Design for Middle School Students)

  • 이윤희;이명아;한혜련;이재경
    • 한국실내디자인학회논문집
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    • 제26권6호
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    • pp.24-32
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    • 2017
  • STEAM education is an effective teaching method to develop self-problem-solving skills through creative thinking. In order to revitalize STEAM education, various program models are being developed recently. The purpose of this study is to develop a STEAM education program based on the project-based learing method that includes the process of solving global environmental problems. The STEAM element was extracted by linking the zero energy house design with the middle school curriculum, and the STEAM education program was developed considering career activities. It was analyzed whether the developed program can improve STEAM core competence and job preparation ability. The education program was conducted for middle school students and the program was evaluated through questionnaires. In order to strengthen the STEAM competency, project-based learning method was applied and it was able to enhance the active problem solving ability of learners. In addition, opportunities for career experience could be provided through career exploration programs and various activities. Through this STEAM education program, it is expected to contribute to cultivating human resources with convergence knowledge and core competency.

사업체노동력조사를 활용한 빈 일자리 수 추정에 대한 정합성 연구 (A Study of Consistency in Estimating the Number of Vacant Jobs Using the Labor Force Survey at Establishments)

  • 박승환
    • 아태비즈니스연구
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    • 제13권3호
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    • pp.329-341
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    • 2022
  • Purpose - The purpose of this study was to investigate consistency in estimating the number of vacant jobs using the two business labor force survey with two different time points of survey. Design/methodology/approach - We studied the cause of the differences in estimating the number of vacant jobs between the monthly sample and the new sample in business labor force survey. Findings - To summarize our findings, As the size of the company increases, the number of vacant jobs in the company also increases, and the probability that the number of vacant jobs in the company is zero decreases. The monthly sample was assessed to have a higher likelihood that the number of vacant jobs in the company was zero and the number of vacant jobs was considerable compared to the local sample. Research implications or Originality - Because local survey sample companies tend to minimize the number of vacant jobs even when they reply under the same conditions, the estimation result of the number of vacant jobs in the current monthly survey differs significantly from the estimation result of the local survey. Divergent "degrees of knowledge of question items," survey methodologies, or investigators could be the causes of the various response trends.

Bloom의 신 교육목표분류학에 따른 슬기로운 생활 교과의 수업 목표 분석 (Analyses of Instructional Objectives of 'Wise Life' Based on Bloom's Revised Taxonomy of Educational Objectives)

  • 이은영;신명경;최취임
    • 한국초등과학교육학회지:초등과학교육
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    • 제31권1호
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    • pp.1-12
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    • 2012
  • The purpose of this study was to explore instructional objectives of 'Wise Life' based on Bloom's Revised Taxonomy of Educational Objectives. It was to extend understanding the 7th and the revised Wise Life 2007 as well. The written objectives of two curriculum of Wise Life were divided into two, the 'knowledge' dimension and the 'cognitive process' dimension based on Bloom's Revised Taxonomy of Educational Objectives. Major activity subjects presented in the 7th and the revised Wise Life 2007 were dominantly the basic inquiry activity types. It was found from this research that the 'factual' knowledge of the 'knowledge' dimension and the 'understand' of the 'cognitive process' dimension took a large proportion of the revised Wise Life 2007 objectives. The 'meta-cognitive' knowledge was increased. 'Remember' of the 'cognitive process' dimension was decreased and the high level objectives as 'analyze' and 'create', in the 'cognitive process' dimension was increased from the 7th to the revised curriculum. The 'factual' knowledge, 'conceptual' knowledge and 'metacognitive' knowledge were engaged with 'understand' and the 'procedural' knowledge were engaged with 'apply'. The 'meta- cognitive' were engaged with 'create' is the 'procedural' knowledge in the revised Wise Life 2007. 'Remember' was decreased. 'Create' was increased in the basic inquiry activities. It was analysed in zero percent of 'Observing', 'Investigating and Presenting', and 'Making'.

무형대용어 해결 기술을 이용한 백과사전 표제어 복원 (Restoring Encyclopedia Title Words Using a Zero Anaphora Resolution Technique)

  • 황민국;김영태;나동열;임수종
    • 한국정보과학회 언어공학연구회:학술대회논문집(한글 및 한국어 정보처리)
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    • 한국정보과학회언어공학연구회 2014년도 제26회 한글 및 한국어 정보처리 학술대회
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    • pp.65-69
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    • 2014
  • 한국어 문장의 경우 문맥상 추론이 가능하다면 용언의 격이 생략되는 현상 즉 무형대용어 (zero anaphora) 현상이 흔히 발생한다. 무형대용어를 채울 수 있는 선행어 (명사구)를 찾는 문제는 대용어 해결 (anaphora resolution) 문제와 같은 성격의 문제이다. 이러한 생략현상은 백과사전이나 위키피디아 등 백과사전류 문서에서도 자주 발생한다. 특히 선행어로 표제어가 가능한 경우 무형대용어 현상이 빈번히 발생한다. 백과사전류 문서는 질의응답 (QA) 시스템의 정답 추출 정보원으로 많이 이용되는데 생략된 표제어의 복원이 없다면 유용한 정보를 제공하기 어렵다. 본 논문에서는 생략된 표제어 복원을 위해 무형대용어의 해결을 기반으로 하는 시스템을 제안한다.

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농촌지역 산업 기술지식의 융합과 지식 네트워크: 순창군 장류산업을 중심으로 (Technological Convergence and Knowledge Network in Rural Area: Fermented Soy Product Manufacturing Industry in Sunchang, Korea)

  • 허동숙;박소현;구양미
    • 한국경제지리학회지
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    • 제19권3호
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    • pp.566-582
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    • 2016
  • 본 연구는 기술지식의 융 복합화로 인해 특정 산업에서 다른 부분으로 영역이 확장되는 양상을 확인하는 것으로, 비수도권 농촌 지역인 전라북도 순창군의 장류산업을 중심으로 분석하였다. 이를 위해 특허출원 자료를 이용하여 기술융합분석과 지식네트워크분석을 실시하였다. 분석 결과, 국내 장류산업은 단순 식품, 식료품 제조 기술에서 기계 기기나 의약품 및 화장품 관련 기술로 폭넓게 융합이 이루어지는 반면 순창군의 장류산업은 발효미생물 관련 기술 방향으로 특화되고 있다. 이는 산업 전체의 융합 경향을 따라 여러 기술 분야로 확장하기 보다는 순창이 갖는 지역자산과 인력에 맞추어 지역산업을 특화시킨 결과라고 판단된다. 순창군 장류산업의 지식네트워크는 지방정부와 대학, 진흥원 등 공공부문이 주도적인 역할을 하고 있고, 최근 조합법인 형태의 출원자와 공공부문의 협력을 통해 지역 내 기술 공유와 확산을 가져오는 것으로 나타났다.

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영지식 증명을 활용한 복원 기능을 가진 검증 가능한 클라우드 기반의 개인 건강기록 (Verifiable Could-Based Personal Health Record with Recovery Functionality Using Zero-Knowledge Proof)

  • 김훈기;김종현;이동훈
    • 정보보호학회논문지
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    • 제30권6호
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    • pp.999-1012
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    • 2020
  • 최근 개인 건강기록의 활용이 증가함에 따라, 개인 건강기록의 개인정보를 보호하는 암호 프로토콜에 대한 연구가 활발하게 이루어지고 있다. 현재 일반적으로 개인 건강기록은 암호화되어 클라우드에 외부 위탁되어 관리되고 있다. 하지만 이 방법은 개인 건강기록의 무결성을 검증하는데 제한적이며, 사용시 필수적으로 복호화가 필요하기 때문에 데이터 가용성이 떨어지는 문제점이 있다. 본 논문에서는 이 문제를 해결하기 위해 Redactable 서명기법과 영지식증명을 사용하여 검증 가능한 클라우드 기반의 개인 건강기록 관리기법을 제안한다. 검증 가능한 클라우드 기반의 개인 건강기록 관리기법은 Redactable 서명기법을 사용함으로써 민감한 정보를 삭제하여 사생활(privacy)을 보존하면서 원본문서의 무결성 검증이 가능하며, 영지식 증명을 사용함으로써 원본문서의 삭제된 부분 외에는 삭제 및 수정되지 않았음을 검증 할 수 있다. 또한 Redact Recovery Authority를 통해 필요한 경우에만 삭제된 부분을 복원할 수 있도록 설계함으로써 기존의 관리기법보다 데이터의 가용성이 증가하도록 설계하였다. 그리고 제안한 기법을 활용한 검증 가능한 클라우드 기반의 개인 건강기록 관리모델을 제안하고, 제안한 기법을 구현함으로써 효율성을 분석하였다.

Efficient User Selection Algorithms for Multiuser MIMO Systems with Zero-Forcing Dirty Paper Coding

  • Wang, Youxiang;Hur, Soo-Jung;Park, Yong-Wan;Choi, Jeong-Hee
    • Journal of Communications and Networks
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    • 제13권3호
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    • pp.232-239
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    • 2011
  • This paper investigates the user selection problem of successive zero-forcing precoded multiuser multiple-input multiple-output (MU-MIMO) downlink systems, in which the base station and mobile receivers are equipped with multiple antennas. Assuming full knowledge of the channel state information at the transmitter, dirty paper coding (DPC) is an optimal precoding strategy, but practical implementation is difficult because of its excessive complexity. As a suboptimal DPC solution, successive zero-forcing DPC (SZF-DPC) was recently proposed; it employs partial interference cancellation at the transmitter with dirty paper encoding. Because of a dimensionality constraint, the base station may select a subset of users to serve in order to maximize the total throughput. The exhaustive search algorithm is optimal; however, its computational complexity is prohibitive. In this paper, we develop two low-complexity user scheduling algorithms to maximize the sum rate capacity of MU-MIMO systems with SZF-DPC. Both algorithms add one user at a time. The first algorithm selects the user with the maximum product of the maximum column norm and maximum eigenvalue. The second algorithm selects the user with the maximum product of the minimum column norm and minimum eigenvalue. Simulation results demonstrate that the second algorithm achieves a performance similar to that of a previously proposed capacity-based selection algorithm at a high signal-to-noise (SNR), and the first algorithm achieves performance very similar to that of a capacity-based algorithm at a low SNR, but both do so with much lower complexity.

특이 섭동 이론에 의한 유연성 관절 매니퓰레이터의 적응제어 (Adaptive control of flexible joint manipulators based on the singular perturbation theory)

  • 김응석;양해원
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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    • pp.7-11
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    • 1991
  • The adaptive control of flexible joint manipulator is the focus of this paper. The full order flexible joint manipulator dynamic system does not allow the determination of a feedback linearization control as for rigid manipulators. This drawback is overcome by a model order reduction based on a singular perturbation strategy. The full order flexible joint manipulator dynamic model is adopted for derivation of the adaptive control law to damp out the elastic oscillations at the joints. It is shown that the joint position error will converge to zero asymptotically and that other signals remain bounded without precise knowledge of parameters of the manipulator and its joint flexibility.

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ElGamal 암호알고리듬을 이용한 메시지 전송 영지식 증명 방식 (Message Sending Zero-Knowledge Interactive Proof System Using ElGamal Cryptographic Algorithm)

  • 엄화영;염흥열;이만영
    • 한국정보보호학회:학술대회논문집
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    • 한국정보보호학회 1992년도 정기총회및학술발표회
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    • pp.165-179
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    • 1992
  • 영지식 대화증명은 인증자(prover)가 비밀정보를 노출시키지 않으면서, 검증자(verifier)와 대화를 통해서 이 비밀정보를 알고 있음을 검증자에게 증명하는 방법이다. 본 논문에서는 ElGamal 암호 알고리듬을 이용하여 메세지 전송과 개인 인중이 동시에 가능한 순방향 영지식 증명 프로토콜과 역방향 영지식 증명 프로토콜을 제안한다. 그리고 전송효율을 송신한 전비트와 정보비트와의 비로 정의하여 각각의 프로토콜의 전송효율을 계산한다.

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