• 제목/요약/키워드: backing

검색결과 234건 처리시간 0.053초

비파괴검사를 위한 PZT 5A 탐촉자에 관한 연구 (A Study on PZT-5A Probe for Nondestructive Inspection)

  • 황현석;정규원;이종덕;송준태
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1996년도 추계학술대회 논문집
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    • pp.245-248
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    • 1996
  • In this study, piezoelectric transducers were designed and manufactured using PZT-5A which had relatively high electromechanical coefficient, NDT system was developed with was able to inspect automatically using stepping motors, PC-Lab, and PC-Scope The optimum design conditions for NDT were presented and verified comparing PZT-5A probes with comercial probes. It was proved with comercial probes. It was proved by simulation and experiments that Epoxy is good as material of matching and backing layers. The envelope was reduced 60% with matching layer and 76% with matching and backing layer. NDT was successfully carried out for aluminum test pieces. Distance error of PZT-5A probe was 2.8%.

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Study on fatigue experiment for transverse butt welds under 2G and 3G weld positions

  • Kang, Sung-Wook;Park, Yong-Man;Jang, Beom-Seon;Jeon, Yu-Chul;Kim, Seong-Min
    • International Journal of Naval Architecture and Ocean Engineering
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    • 제7권5호
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    • pp.833-847
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    • 2015
  • Although the transverse butt weld method with ceramic backing strip has been widely used in various industrial fields for its fabricational convenience, it is rarely used in offshore industries since the fatigue strength of the weld joint has not been proved sufficiently. This study conducted fatigue tests for series of butt weld specimens with horizontal (2G) and vertical (3G) welding positions in order to verify the fatigue strength compared to S-N curve by DNV (Det Norske Veritas), IIW (International Institute of Welding) and Eurocode 3. The difference of the 2G specimens and the 3G specimens are investigated in terms of angular distortion and the effect on the fatigue strength are analyzed.

Evaluating Innovation Policies in Australian Government: BACKING AUSTRALIA'S ABILITY

  • 문용은
    • 한국디지털정책학회:학술대회논문집
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    • 한국디지털정책학회 2003년도 창립학술대회
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    • pp.101-114
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    • 2003
  • In industrialised countries, innovation is a key source of economic growth. Research is a key driver of technological innovation and involves the process of systematic investigation and/or experimentation to discover new knowledge. The Governments' industry innovation policy supports a business focus on Research and Development (R&D) through a range of programs in order to achieve these aims. The Innovation Statement, launched by the Australian Prime Minister in January 2001, commits an additional $3 billion over five years to encourage and support innovation. The Australian Government aims to build world competitive firms and strong research capability in industry to strengthen Australia's international competitiveness and increase national prosperity. It develops policies and programs to enhance investment in innovation. The Australian Government also undertakes analysis and comparisons of innovation policies, instruments and approaches to maintain a leading-edge National Innovation System. This includes analysis of the innovation activities of other nations, and evaluation of the impacts of innovation policies and programs on Australia's institutions and enterprises. This paper examines Australia's Innovation policies, Backing Australian Ability.

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DNA 코딩 기반의 하이브리드 알고리즘을 이용한 Truck-Trailer Backing Problem의 퍼지 모델링 (Fuzzy Modeling of Truck-Trailer Backing Problem Using DNA Coding-Based Hybrid Algorithm)

  • 김장현;주영훈;박진배
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 하계학술대회 논문집 D
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    • pp.2314-2316
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    • 2000
  • In the construction of successful fuzzy models and/or controllers for nonlinear systems, identification of a good fuzzy Neural inference system is an important yet difficult problem, which is traditionally accomplished by trial and error process. In this paper, we propose a systematic identification procedure for complex multi-input single- output nonlinear systems with DNA coding method.DNA coding method is optimization algorithm based on biological DNA as are conventional genetic algothms (GAs). We also propose a new coding method for applying the DNA coding method to the identification of fuzzy Neural models. To acquire optimal TS fuzzy model with higher accuracy and economical size, we use the DNA coding method to optimize the parameters and the number of fuzzy inference system.

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Evaluating Innovation Policies in Australian Government: Backing Australia's Ability

  • 문용은;조셉윤
    • 디지털융복합연구
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    • 제1권1호
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    • pp.31-44
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    • 2003
  • In industrialised countries, innovation is a key source of economic growth. Research is a key driver of technological innovation and involves the process of systematic investigation and/or experimentation to discover new knowledge. The Governments' industry innovation policy supports a business focus on Research and Development (R&D) through a range of programs in order to achieve these aims. The Innovation Statement, launched by the Australian Prime Minister in January 2001, commits an additional 53 billion over five years to encourage and support innovation. The Australian Government aims to build world competitive firms and strong research capability in industry to strengthen Australia's international competitiveness and increase national prosperity. It develops policies and programs to enhance investment in innovation. The Australian Government also undertakes analysis and comparisons of innovation policies, instruments and approaches to maintain a leading-edge National Innovation System. This includes analysis of the innovation activities of other nations, and evaluation of the impacts of innovation policies and programs on Australia's institutions and enterprises. This paper examines Australia's Innovation policies, Backing Australian Ability.

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퍼지논리와 유전알고리즘을 이용한 트랙터-트레일러의 후진제어 시뮬레이션 (Backward Control Simulation of Tractor-Trailer Using Fuzzy Logic and Genetic Algorithms)

  • 조성인;기노훈
    • Journal of Biosystems Engineering
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    • 제20권1호
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    • pp.87-94
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    • 1995
  • When farmer loads and unloads farm products with a trailer, linked to a tractor, the tractor-trailer is backed up to the loading duck. However, travelling backward is not easy and takes a time for even skilled operators. Therefore, unmanned backing up is necessary to save the effort. A backward controller of tractor-trailer was simulated using fuzzy logic and genetic algorithms. Operators drive the tractor-trailer back and forth several times for backing up to the loading duck. As the operators did it, a backward controller was designed using fuzzy logic. And genetic algorithms was applied to improve the performance of the backward controller. With the strings coded with the fuzzy membership functions, genetic operations were carried out. After 30 generations, the best fitted fuzzy membership functions were found. Those membership functions were used in the fuzzy backward controller. The fuzzy controller combined with genetic algorithms showed the better results than the fuzzy controller did alone.

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드럼 브레이크의 스퀼 소음에 관한 연구 (A Study on the Squeal Noise of Drum Brakes)

  • 이장무;김종현;유성우;안창기
    • 한국정밀공학회지
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    • 제15권9호
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    • pp.111-116
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    • 1998
  • The squeal of drum brakes was investigated numerically and experimentally. Modal testings were performed for shoes, drums, backing plates and their assemblies. In order to predict the squeal phenomena, stability analysis was performed based on a simplified self-excited vibration model. Based on modal testings, the dynamic properties of the brake elements and the parameters used in this analysis were determined. The geometries of shoes and drums were also considered. The result shows that the modification methods of the shoe and the drum design are feasible for noise reduction.

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논-스캘럽 블록 조인트 용접법 개발 (Development of Non-Scallop Block Joint Welding Method)

  • 김호경;고대은
    • 한국산학기술학회논문지
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    • 제15권9호
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    • pp.5419-5424
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    • 2014
  • 용접 스캘럽은 작은 사분원 또는 반원 형상의 구멍으로서 용접의 작업성 향상을 위한 목적으로 용접선이 교차하는 위치에 시공된다. 선체 블록의 탑재 단계에서는 수많은 T-bar 조인트 용접이 수행되어야하며, 플랜지-웨브의 교차용접이 완료된 후에 육성용접을 통해 모든 스캘럽을 메공하는데 많은 생산시수가 소요된다. 본 연구에서는 특별한 타입의 CBM(ceramic backing material)을 고안하여 T-bar 조인트 용접 시 플랜지-웨브의 교차용접 지점에 시공되던 스캘럽을 삭제함으로써 논-스캘럽 블록 조인트 용접 공법을 개발하였다. 플랜지간 용접 시 플랜지 이면에 접촉한 웨브의 V 용접개선에 삽입이 용이하도록 CBM을 웨지 형상으로 제작하였고 웨브간 용접 개선의 루트갭에 맞추어 불필요한 부분의 절단이 용이하도록 예비 절단면들을 톱니 형상으로 배치하였다. 조선소의 실제 용접조건에 기초한 일련의 실험을 통하여 개발된 논-스캘럽 용접 공법의 유용성을 확인하였다.

FGB SAW 용접부 물성에 미치는 Ni과 Mo의 영향에 관한 연구 (Effect of Ni and Mo on Mechanical Properties of Submerged Arc Welds with Flexible Glasswool Backing)

  • 지춘호;최준태;김대주
    • 대한용접접합학회:학술대회논문집
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    • 대한용접접합학회 2009년 추계학술발표대회
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    • pp.55-55
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    • 2009
  • FGB(Flexible Glasswool Backing) Submerged Arc Welding has been one of the main welding processes for one side butt welding in shipbuilding industries, which can efficiently improve the welding productivity by the addition of a supplementary filler metal into the molten weld pool. As recent ships have become larger in size, the application of high tensile and higher grade of steels has been continuously increased. Single pass FGB SA welding process accompanies such a high heat input when welding thick plates that the mechanical properties of weld metal can be dramatically degraded. This study has been performed in order to obtain high toughness and tensile properties of high heat input FGB SA welds, and to evaluate the effect of alloy elements on their mechanical properties. To complete welding 25mm-thick EH36 grade steel plate by single pass, 1.2mm diameter and 1.0mm long cut wires has been distributed in the groove before welding, and three different test coupons have been made using C-1.5%Mn, C-1.8%Mn-0.5%Mo, and C-1.4%Mn-1.7%Ni cut wires to investigate the influence of nickel(Ni) and molybdenum(Mo) on the mechanical properties of welds. Test results showed that the addition of Ni and Mo effectively promotes the formation of Acicular Ferrite(AF), while significantly reducing the amount of Grain Boundary Ferrite(GBF) in weld metal microstructures, which resulted in a beneficial effect on low temperature impact toughness and strength.

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