• 제목/요약/키워드: Smart Material

검색결과 967건 처리시간 0.023초

Vibration control of laminated composite plates using embedded smart layers

  • Reddy, J.N.;Krishnan, S.
    • Structural Engineering and Mechanics
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    • 제12권2호
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    • pp.135-156
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    • 2001
  • Analytical solutions and finite element results of laminated composite plates with smart material layers embedded in them are presented in this study. The third-order plate theory of Reddy is used to study vibration suppression characteristics. The analytical solution for simply supported boundary conditions is based on the Navier solution procedure. The velocity feedback control is used. Parametric effects of the position of the smart material layers, material properties, and control parameters on the suppression time are investigated. It has been found that (a) the minimum vibration suppression time is achieved by placing the smart material layers farthest from the neutral axis, (b) using thinner smart material layers have better vibration attenuation characteristics, and, (c) the vibration suppression time is larger for a lower value of the feedback control coefficient.

무선 랜 시스템용 스마트 스킨의 좌굴 특성 연구 (Characteristics of Smart Skin for Wireless LAN system under Buckling Load)

  • 전지훈;유치상;황운봉;박현철;박위상
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2001년도 춘계학술발표대회 논문집
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    • pp.42-45
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    • 2001
  • The characteristics of smart skin for wireless LAN system under compression load are investigated. The smart skin structure is composed of 3 layers of face material and 2 layers of core material. Theoretical formula for determining buckling load is derived by Rayleigh-Ritz method and compared with experimental result. The maximum length of specimen that buckling does not occur is determined by only face material. In the experiment, if load supporting capability and the antenna property such as radiation pattern and reflection coefficient were examined.

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지능재료를 이용한 차세대 철도차량기술 (Advanced Railway Vehicle Technology using Smart Materials)

  • 김재환;강부병;김형진;정흥채;최성규
    • 한국철도학회논문집
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    • 제6권4호
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    • pp.252-256
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    • 2003
  • Smart materials can adapt to changes of environment like living organs in nature such that they can maximize the performance and minimize the maintenance expense of engineering systems. Such materials have been paid attention ten years ago and applied in the area of industry, aerospace, transportation and civil structures. This paper summarizes smart material technology and shows some application examples in railway vehicles. Also, its future of smart material technology in railway vehicle technology is envisaged based on its possibility and practical aspect.

Smart body armor inspired by flow in bone

  • Tate, Melissa Louise Knothe
    • Smart Structures and Systems
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    • 제7권3호
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    • pp.223-228
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    • 2011
  • An understanding of biomaterials' smart properties and how biocomposite materials are manufactured by cells provides not only bio-inspiration for new classes of smart actuators and sensors but also foundational technology for smart materials and their manufacture. In this case study, I examine the unique smart properties of bone, which are evident at multiple length scales and how they provide inspiration for novel classes of mechanoactive materials. I then review potential approaches to engineer and manufacture bioinspired smart materials that can be applied to solve currently intractable problems such as the need for "smart" body armor or decor cum personal safety devices.

리튬이온전지를 이용한 노트북 PC용 고성능 Smart Battery의 개발 (Development of High-Performance Smart Battery for Notebook PCs with Lithium Ion Battery)

  • 김현수;문성인;윤문수;고병희;김동훈
    • 한국전기전자재료학회논문지
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    • 제16권11호
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    • pp.1047-1054
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    • 2003
  • Smart battery pack (SBP) for notebook PCs was developed using a cylindrical-type lithium ion battery. Batteries were connected with three serial and two parallel, the nominal capacity and the maximum load of SBP was 4,000mAh and 4.0A, respectively. The SBP was composed of a protection IC, by which safety of lithium ion batteries is maintained against overcharge, overdischarge and overcurrent, and a smart IC, which calculates the remaining capacity and the remaining run time. In matching test on notebook PC using Battery Mark 4.0, real and smart data of END voltage coincided nearly and LB and LLB signal worked norma]]y. And there were errors of less than 1% between the real and the smart data on the residual capacity in the charge and discharge test.

지능센서의 센싱능력 평가를 위한 평가기법 개발 (Development Estimation Method to Estimate Sensing Ability of Smart Sensors)

  • 황성연;마사히코 무루조노;김영문;홍동표
    • 한국공작기계학회논문집
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    • 제15권2호
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    • pp.99-106
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    • 2006
  • In this paper, the new method that estimates a sensing ability of smart sensor will be proposed. A study is estimation method that evaluates sensing ability about smart sensor respectively. According to acceleration(g) and displacement changing, we estimated sensing ability of smart sensor using SAI(Sensing Ability Index) method respectively. Smart sensors was made fer experiment. The types of smart sensor are two types(hard and soft smart sensor). Smart sensors developed for recognition of material. Experiment and analysis are executed for estimate the SAI method. In develop a smart sensor, the SAI method will be useful for finding optical design condition of smart sensor that can sense a material. And then dynamic characteristics of smart sensors(frequency changing, acceleration changing, critical point, etc.) are evaluated respectively through new method(SAI) that use the power spectrum density. Dynamic characteristic of sensor is evaluated with SAI method relatively. We can use the SAI for finding critical point of smart sensor, too.

Self-Illuminated Smart Window Based on Polymer-Dispersed Liquid Crystal Mixed with Cu-doped ZnS

  • Kim, Eun Mi;Heo, Gi-Seok
    • 한국전기전자재료학회논문지
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    • 제35권6호
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    • pp.562-567
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    • 2022
  • Novel self-illuminated smart windows were fabricated consisting of Cu-doped ZnS (ZnS:Cu) powder and polymer-dispersed liquid crystal (PDLC). This smart window shows not only switchable transparency but also self-illumination without any attachable luminous body. Its electro-optical characteristics, transmittance, and luminance were investigated in relation to various applied voltages and composition ratios. The optical transmittance and luminous intensity increased with increasing applied voltages. However, the optical transmittance decreased with increasing ZnS:Cu powder content. One of the self-illuminated smart windows, which was fabricated with 9 wt% of ZnS:Cu, achieved the optical transmittance of 60.5% (at 550 nm) and the luminance of 11.0 cd/m2 at 100 V. This smart window could be used as a normal switchable smart window in daytime and light-emitting signage at night.

중소형 무인기 브레이크 시스템용 복합형 지능재료펌프 설계 (Design of the Compound Smart Material Pump for Brake System of Small·Medium Size UAV)

  • 이종훈;황재혁;양지연;주용휘;배재성;권준용
    • 항공우주시스템공학회지
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    • 제9권3호
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    • pp.1-7
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    • 2015
  • In this study, the design of compound smart materials hydraulic pump that can be applied to a small-medium size UAV having a limited space envelope and weight has been conducted. Compound Smart Material Pump(CSMP) proposed in this paper is composed of a pressurize pump and a flow pump for supplying the high pressure and fluid displacement to overcome the disadvantages of the piezoelectric actuator which has a small strain. Though this compound smart material pump has been designed as small size and lightweight as possible, it can sequentially supply the sufficient large flow rate and pressure required for the brake operation. For the design of CSMP, about 2,700 kg (6,000 lb) class fixed wing manned aircraft was selected. Based on the established requirements, the design of the CSMP have been done by strength, vibration, and fluid flow analysis.

수동/능동적 방법을 혼용한 압전지능패널의 광대역 전달 소음저감성능 (Transmitted Noise Reduction of Piezoelectric Smart Panels using Passive/Active Method in Wide Range frequency)

  • 이중근;박우철
    • 한국산학기술학회논문지
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    • 제2권2호
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    • pp.73-79
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    • 2001
  • 압전재료를 이용한 지능패널의 전달음 저감성능을 실험적으로 연구하였다. 제안된 압전지능패널은 압전 감지기와 작동기가 부착되어 있는 주구조물에 흡음재가 한 쪽면에 부착된 구조이다. 이는 저주파에서 능동적 방법과 고주파에서 수동적방법을 혼용한 개념이다. 이 개념을 증명하기 위하여 음향실험을 수행하였다. 음향실험을 위하여 음향터널을 설계, 제작하여 음향특성을 실험하였다. 음향 특성실험을 통하여 800 Hz가지 평면파특성을 나타내었다. 단일패널에 흡음재를 부착한 지능패널은 첫번째 공진주파수영역을 제외한 중주파수영역에서 뚜렸한 소음저감성능을 나타내었다. 첫번째 공진주파수에 대하여 반전회로를 이용한 능동제어를 수행하여 약 10 dB소음저감을 이루었다. 또한, 공기층을 갖는 이중지능패널에 대한 실험을 통하여 공진주파수에서 뿐만 아니라 넓은 영역에서 좋은 소음저감성능을 보였다. 수동적 방법과 능동적 방법을 혼용한 압전지능패널은 넓은 주파수 영역에서의 소온저감대책으로 유망한 기술이다.

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자성 분말 기반 소프트 자성 액츄에이터 및 센서 연구 동향 (Recent Advances in Soft Magnetic Actuators and Sensors using Magnetic Particles)

  • 송현서;이하준;김정효;김지윤
    • 한국분말재료학회지
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    • 제28권6호
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    • pp.509-517
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    • 2021
  • Smart materials capable of changing their characteristics in response to stimuli such as light, heat, pH, and electric and magnetic fields are promising for application to flexible electronics, soft robotics, and biomedicine. Compared with conventional rigid materials, these materials are typically composed of soft materials that improve the biocompatibility and allow for large and dynamic deformations in response to external environmental stimuli. Among them, smart magnetic materials are attracting immense attention owing to their fast response, remote actuation, and wide penetration range under various conditions. In this review, we report the material design and fabrication of smart magnetic materials. Furthermore, we focus on recent advances in their typical applications, namely, soft magnetic actuators, sensors for self-assembly, object manipulation, shape transformation, multimodal robot actuation, and tactile sensing.