• 제목/요약/키워드: the development of proof

검색결과 326건 처리시간 0.031초

방진용 폴리우레탄 매트의 물리적 특성과 안정성 향상에 관한 연구 (A Study on Quality Characteristic and Stability Improvement of Vibration-Proof Polyurethane Mat)

  • 우경하;이창호
    • 대한안전경영과학회지
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    • 제21권1호
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    • pp.1-7
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    • 2019
  • Along with industrial development, various architectural structures have become bigger and higher, leading to an expansion in the size and capacity of construction equipment. And with the development of public transportation, the use of subways as a means of transportation in the city center is increasing, so that vibrations and structural noises are emerging as a new environmental issue. Considering that architectural structures may be used from several decades to hundreds of years after the time of construction, they can be seen as semi-permanent. Due to changes in the vibration-proof polyurethane mats installed in the foundation of these structures, settling may occur and vibration reduction may become inadequate. Therefore, in view of service life, it is necessary to have a high-level standard of reliability and stability. In accordance with this, the Floating Floor System, which uses soft polyurethane foam and can be constructed within a relatively short period of time, has excellent vibration resistant characteristics. It is presented as a great alternative solution to the issue of vibrations caused by subways, railways and building structures. At present, vibration-proof polyurethane mats have been developed up to the same product level as in other advanced countries. However, in the construction of structure foundations, the physical properties of this product and its shape incur changes. If they are installed as such in the structure of a building, it may cause significant impact on stability, requiring that this cause be urgently identified and improved.

블록체인 DPoS 합의 알고리즘을 활용한 IoT 장치 관리 시스템 개발 (Development of IoT Device Management System Using Blockchain DPoS Consensus Algorithm)

  • 김미희;김영민
    • 전기전자학회논문지
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    • 제23권2호
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    • pp.508-516
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    • 2019
  • 다양한 IoT 기기로 구성된 스마트 홈에서는 편리하고 효율적인 서비스를 제공한다. 그러나 사적인 영상과 음성과 같은 민감한 정보까지 수집 및 처리될 뿐 아니라 인터넷을 통해 공유될 수 있어서 보안이 중요하다. 이러한 스마트 홈 IoT 장치 관리를 위하여 데이터 무결성 및 안전성을 제공하기 위해 블록체인 기술을 활용하고자 한다. 본 논문에서는 기존 검증을 위한 연산을 지속적으로 수행해야 하는 PoW(작업 증명) 블록체인에서 아닌 네트워크에 축적된 지분을 통해 블록을 검증하는 PoS(지분 증명), 그 중에서 확장성 부분을 해결하고자 하는 DPoS(위임 지분 증명) 방식으로 스마트 홈 IoT 환경에 적절한 보안용 블록체인 체계를 제안한다. DPoS 체계인 EOSIO 기반으로 제안시스템을 구현하여 실현가능성을 보이고, 성능평가를 통해 트랜잭션 처리 속도 측면의 성능 향상을 보이고자 한다.

철도차량 부쉬용 방진 천연고무의 카본블랙 강화제에 의한 피로수명과 파단 모폴로지 변화 연구 (A study on the change of the fatigue life and the fracture morphology due to the carbon black on the Natural rubber for vibration-proof)

  • 김재훈;허현무
    • 한국철도학회논문집
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    • 제8권1호
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    • pp.21-26
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    • 2005
  • The effects of carbon black on the fatigue lift and the fracture morphology and the carbon black dispersion of the carbon-black filled natural rubbers, for the vibration-proof, were investigated. Different kinds of carbon blacks resulted in different fatigue lift and fracture morphologies, which are classified by micro-scale and macro-scale fracture morphologies. These results be related to the size distribution of carbon black particles, the development of the carbon black agglomerate and the combine forces between the carbon black and the natural rubber.

대전된 분체의 정전기제거장치 개발 및 특성에 관한 연구 (A Study for Development and Characteristics of Electrostatic Eliminator for Charged Particles)

  • 정용철;김준삼;이동훈
    • 한국안전학회지
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    • 제21권3호
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    • pp.22-30
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    • 2006
  • On this study, we developed the electrostatic eliminator for charged particles in manufacturing process. The characteristics of the electrostatic eliminator were investigated, which is two kinds. The first one is Electrical Corona Discharged Type Ionizer. The second one is Photo Ionizer in using soft X-ray. From the experiment, we have obtained the following results. In case of Electrical Corona Discharged Ionizer, neutralization efficiency of charged particles were approximately saturated to 98% over 6.0kV, but as it is non-explosion proof, can not be used in flammable particle treatment process. While in case of photo Ionizer in using soft X-Ray, neutralization efficiency of charged particles were approximately 95%, and more its structure is explosion proof, could be used in flammable particle treatment process.

생태방음벽에 개발에 사용되는 식물종의 성장에 관한 연구 (Development of Ecological Sound Proof Wall by the germination of plant species at different Environmental Condition)

  • 사리타 버셀;조해용;한세권
    • 한국산학기술학회:학술대회논문집
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    • 한국산학기술학회 2009년도 추계학술발표논문집
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    • pp.100-102
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    • 2009
  • Effect of temperature, pH and soil depth on germination of Dianthus chinensis, Dianthus barbatus, and Perennial pennant were investigated in growth chamber and soil condition at the ratio of 7:3 (natural soil and organic soil) in laboratory condition. the optimum temperature for seed germination was recorded for $20^{\circ}C-\;25^{\circ}C$. Maximum germination was observed for Dianthus barbatus (76%) where as in soil condition Perennial pennant (51%) showed maximum germination at 1 cm soil depth. Similarly, optimum pH for seed germination was at pH 6 in all the species. So in lower pH (at pH4) seed germination was inhibited. Germination of these selected species at different environmental condition help to construct the ecological sound proof wall to mitigate the noise especially in urban areas.

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액체저장탱크의 지진하중과 풍하중 설계기준 고찰 (A Study on the Design Criteria of Seismic and Wind Loads for Cylindrical Liquid Storage Steel Tanks)

  • 이남헌;오택열;안주옥;최선영;박종률;김학영
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2005년도 춘계학술대회 논문집
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    • pp.1412-1415
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    • 2005
  • Special considerations on the design of liquid storage tanks should be taken into account for seismic and wind loads. But Korean industrial standard KS B 6225 does not specify detailed guidelines for a design. It is therefore necessary to improve design guidelines for a seismic and wind-proof design in KS B 6225. The purpose of this study is provide a basis for the development of improved seismic and wind-proof design procedures, especially about seismic and wind loads.

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친환경 옥상방수공법 개발에 관한 연구 (A study on the Development of an Eco-friendly Rooftop Waterproofing Method)

  • 오동식;고성석
    • 한국건축시공학회지
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    • 제10권5호
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    • pp.103-111
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    • 2010
  • 본 연구는 현행 옥상 방수공법이 가지고 있는 문제점과 그 원인을 분석 파악하고, 이에 따른 대체 공법을 제안함으로써 옥상 방수공법 발전에 기여하는데 있다. 이와 같은 측면에서 본 연구에서는 설계 및 시공상의 누수에 따른 문제점 분석을 통해 이를 저감시키고, 시공 품질향상, 노동력의 절감, 공기단축, 환경문제 개선 등 기존 방수공법의 문제점을 보완한 친환경적 복합방수공법을 개발하고 기존공법과의 분야별 성능 비교 분석 및 현장적용 시공성능 평가를 실시하여 방수공법 특성과 결론을 도출하였다.

폴리머 housing형 피뢰기의 개발과 특성 평가 (Development and Characteristics Evaluation of Polymer Housing Type Arresrter)

  • 조한구;김인성
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1997년도 춘계학술대회 논문집
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    • pp.82-85
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    • 1997
  • This paper describes the development of new type arrester for 22.9kV class distribution lines, with polymer insulating materials applied to their housings. The new arrester employs silicone insulating material for its housing, instead of the conventional porcelain housing, aiming at reduction in size and weight and explosion proof against internal short circuit failure. And, since the design of sheds is not restricted. it is possible to provide a long surface leakage distance per strike length and improve anti-contamination performance.

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Using Practice Context Models to Knowledge Management in Proof-of-Concept Activities: A Contribution of Knowledge Networks and Percolation Theory

  • Neto, Antonio Jose Rodrigues;Borges, Maria Manuel;Roque, Licinio
    • Journal of Information Science Theory and Practice
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    • 제9권1호
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    • pp.1-23
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    • 2021
  • This study introduces novel research using Practice Context Models supported by Knowledge Networks and Percolation Theory with the aim to contribute to knowledge management in Proof-of-Concept (PoC) activities. The authors envision this proposal as a potential instrument to identify network structures based on a percolation (propagation) threshold and to analyze the importance of nodes (e.g., practitioners, practices, competencies, movements, and scenarios) during the percolation of knowledge in PoC activities. After thirty months immersed in the natural PoC habitat, acting as observers and practitioners, and supported by an ethnographic exercise and a designer-research mindset, the authors identified the production of meaning in PoC activities occurring in a hermeneutic circle characterized by the presence of several knowledge networks; thus, discovering the 'natural knowledge' in PoC as a spectrum of cognitive development spread throughout its network, as each node could produce and disseminate certain knowledge that flows and influences other nodes. Therefore, this research presents the use of Practice Context Models 'connected' to Knowledge Networks and Percolation Theory as a potential and feasible proposal to be built using the attribution of values (weights) to the nodes (e.g., practitioners, practices, competencies, movements, scenarios, and also knowledge) in the context of PoC with the aim to allow the players (e.g., PoC practitioners) to have more flexibility in building alliances with other players (new nodes); that is, focusing on those nodes with higher value (focus on quality) in collaboration networks, i.e., alliances (connections) with the aim to contribute to knowledge management in the context of PoC.

연구 프로그램으로서의 힐버트 계획 (Hilbert's Program as Research Program)

  • 정계섭
    • 한국수학사학회지
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    • 제24권3호
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    • pp.37-58
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    • 2011
  • 수리 논리학의 발전은 상당 부분 힐버트 (D. Hilbert, 1862~1943)의 증명이론(Beweistheorie)에 뿌리를 두고 있다. 흔히 '힐버트 계획' (Hilbert's program)으로 불리는 이 계획의 목표는 형식적 공리론적 방법에 의해 수학의 모든 명제와 증명을 형식화하고 이 형식 체계의 완비성과 무모순성 증명을 통해 고전 수학을 '구원' 하고, 수학의 토대를 공고히 하자는 데에 있다. 1931년 괴델의 제 1정리에 의해 결정불가능 명제의 존재가 드러나면서 완전성이 위기를 맞고, 제 2정리에 의해 무모순성의 확립이 무산될 위기에 처한다. 그러나 '상대적' 내지 '부분적' 힐버트 계획은 효과적인 연구 프로그램으로서 살아 있다고 말하는 학자들이 적지 않다. 우리는 특히 힐버트 계획 이 오늘날 구성주의 수학의 발전에 동력을 제공하고 있다는 점을 커리-하워드 대응 (Curry-Howard Correspondence)을 통하여 부각시키고자 했다. 자연연역에서 증명 (proof) 이 바로 컴퓨터 프로그램 (computer program) 에 다름 아니라는 사실에 의해 수학의 형식화 (formalization)는 새로운 조명을 받게 된 것이다. 요컨대 힐버트 계획은 컴퓨터 과학에서 알고리듬 (algorithm) 이라는 핵심개념에 가장 잘 부합되는 것이다.