• Title/Summary/Keyword: smart materials

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Technical Trends of Flexible, Transparent Electromagnetic Interference Shielding Film (유연한 투명 전자기 간섭 차폐 필름의 기술개발 동향)

  • Lim, Hyun-Su;Oh, Jung-Min;Kim, Jong-Woong
    • Journal of the Microelectronics and Packaging Society
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    • v.28 no.1
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    • pp.21-29
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    • 2021
  • Recently, semiconductor chips and electronic components are increasingly being used in IT devices such as wearable watches, autonomous vehicles, and smart phones. As a result, there is a growing concern about device malfunctions that may occur due to electromagnetic interference being entangled with each other. In particular, electromagnetic wave emissions from wearable or flexible smart devices have detrimental effects on human health. Therefore, flexible and transparent electromagnetic interference (EMI) shielding materials and films with high optical transmittance and outstanding shielding effectiveness have been gaining more attention. The EMI shielding films for flexible and transparent electronic devices must exhibit high shielding effectiveness, high optical transmittance, high flexibility, ultrathin and excellent durability. Meanwhile, in order to prepare this EMI shielding films, many materials have been developed, and results regarding excellent EMI shielding performance of a new materials such as carbon nano tube (CNT), graphene, Ag nano wire and MXene have recently been reported. Thus, in this paper, we review the latest research results to EMI shielding films for flexible and transparent device using the new materials.

Overview on Smart Sensor Technology for Biometrics in IoT Era (사물인터넷 시대의 생체인식 스마트 센서 기술과 연구 동향)

  • Kim, Kwang-Seok;Kim, Dae Up
    • Journal of the Microelectronics and Packaging Society
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    • v.23 no.2
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    • pp.29-35
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    • 2016
  • With the pace of rapid innovation in technology of IoT (Internet of Things) and smart devices, biometric technology becomes one of the most progressive industries. Recent trends in biometrics show most are focused on embedding biometric sensors in mobile devices for user authentication. Multifactor biometrics such as fingerprint, retina, voice, etc. are considering as identification system to provide users with services more secured and convenient. Here we, therefore, demonstrate some major technologies and market trends of mobile biometric technology with its concerns and issues.

A Study on the Measurement of Stress Intensity Factors for the Fatigue Crack Propagation (피로 균열 진전에 따른 응력확대계수 측정에 관한 연구)

  • Oh, Dong-Jin;Kim, Myung-Hyun
    • Journal of Welding and Joining
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    • v.30 no.6
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    • pp.80-85
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    • 2012
  • Fatigue cracks in structural components are the most common cause of structural failure when exposed to fatigue loading. In this respect, fatigue crack detection and structural health assessment are very important. Currently, various smart materials are used for detecting fatigue crack and measurement of SIFs(Stress Intensity Factors). So, this paper presented a measurement of SIFs using MFC(Micro Fiber Composite) sensor which is the one of the smart material. MFC sensor is more flexible, durable and reliable than other smart materials. The SIFs of Mode I(K I) as well as Mode II(K II) based on the piezoelectric constitutive law and fracture mechanics are calculated. In this study, the SIF values measured by MFC sensors are compared with the theoretical results.

Vibration Control of Beam Containing ER Fluid Using PPF Control Scheme (PPF 제어기법을 적용한 전기점성유체가 함유된 보의 진동제어)

  • Yun Shin-Il;Chin Do-Hun;Yoon Moon-Chul
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.14 no.3
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    • pp.32-37
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    • 2005
  • Several types of smart materials and control scheme are available to adjust the structure actively in various external disturbances. A control scheme was introduced for a specific material. But the effectiveness of the control scheme has some limitation according to the choice of the smart materials and the response of the structure. The ER(Electrorheological) fluid is adequate for a large control force, and the PZT(lead zirconate titanate) patches are suitable for small but arbitrary control force at any point of the structure. It can be used for active control of structure by changing the dynamic characteristics of the structure. But it has some difficulty in suppressing the excited vibration in broad band. To compensate this resonance of the controlled structure, a hybrid controller was constructed using PPF(Positive position feedback) control with PZT and ER fluid control.

Development of Smart Education System using Digital Pen (디지털 펜을 활용한 스마트 교육 시스템 개발)

  • Cho, Sang Gyu;Cho, Young Im
    • Journal of Engineering Education Research
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    • v.18 no.6
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    • pp.52-56
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    • 2015
  • Usually, students write on a paper using writing materials and submit it to teachers when they do a homework or take an exam. However, there are temporal and spacial constraints because teachers and students should be in the same place at the time in this system. In addition, it is hard for teachers to maintain numerous papers from students. Applying a digital pen produced by Pen Generations Corporation to education system, we developed a smart education system transmitting image data from written papers using digital pen. As a result, teachers and students can use this system without any constraints. In addition, teachers are able to maintain their papers from students more effectively.

Study on the Fiber Bragg Grating Sensors for Smart Structures and Their Applications (스마트 구조물용 광섬유 격자센서 및 그 응용)

  • Kim Ki-Soo;Song Young-Chul;Pang Gi-Sung
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 2004.04a
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    • pp.115-118
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    • 2004
  • In this paper, a Fiber Bragg Grating (FBG) sensor system for smart structures is described. FBGs are well-suited for long term and extremely severe experiments, where traditional strain gauges fail. In the system, a reflect wave-length measurement method which employs a tunable light source to find out the center wave-length of FBG sensor is used. We applied the FBG system to composite repairing structures and beam column joint of building structure. We also applied the system to nuclear energy power plant for structural integrity test to measure the displacement of the structure under designed pressure and to check the elasticity of the structure by measuring the residual strain. The system works very well and it is expected that it can be used for a real-time strain, temperature and vibration detectors as parts of smart structures.

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IoT Connectivity Application for Smart Building based on Analysis and Prediction System

  • COROTINSCHI, Ghenadie;FRANCU, Catalin;ZAGAN, Ionel;GAITAN, Vasile Gheorghita
    • International Journal of Computer Science & Network Security
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    • v.21 no.9
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    • pp.103-108
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    • 2021
  • The emergence of new technologies and their implementation by different manufacturers of electronic devices are experiencing an ascending trend. Most of the time, these protocols are expected to reach a certain degree of maturity, and electronic equipment manufacturers use simplified communication standards and interfaces that have already reached maturity in terms of their development such as ModBUS, KNX or CAN. This paper proposes an IoT solution of the Smart Home type based on an Analysis and Prediction System. A data acquisition component was implemented and there was defined an algorithm for the analysis and prediction of actions based on the values collected from the data update component and the data logger records.

Triboelectric Nanogenerators for Self-powered Sensors

  • Rubab, Najaf;Kim, Sang-Woo
    • Journal of Sensor Science and Technology
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    • v.31 no.2
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    • pp.79-84
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    • 2022
  • Self-powered sensors play an important role in everyday life, and they cover a wide range of topics. These sensors are meant to measure the amount of relevant motion and transform the biomechanical activities into electrical signals using triboelectric nanogenerators (TENGs) since they are sensitive to external stimuli such as pressure, temperature, wetness, and motion. The present advancement of TENGs-based self-powered wearable, implantable, and patchable sensors for healthcare monitoring, human body motion, and medication delivery systems was carefully emphasized in this study. The use of TENG technology to generate electrical energy in real-time using self-powered sensors has been the topic of considerable research among various leading scholars. TENGs have been used in a variety of applications, including biomedical and healthcare physical sensors, wearable devices, biomedical, human-machine interface, chemical and environmental monitoring, smart traffic, smart cities, robotics, and fiber and fabric sensors, among others, as efficient mechanical-to-electric energy conversion technologies. In this evaluation, the progress accomplished by TENG in several areas is extensively reviewed. There will be a discussion on the future of self-powered sensors.

Seismic response control of buildings using shape memory alloys as smart material: State-of-the-Art review

  • Eswar, Moka;Chourasia, Ajay;Gopalakrishnan, N.
    • Earthquakes and Structures
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    • v.23 no.2
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    • pp.207-219
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    • 2022
  • Seismic response control has always been a grave concern with the damage and collapse of many buildings during the past earthquakes. While there are several existing techniques like base isolation, viscous damper, moment-resisting beam-column connections, tuned mass damper, etc., many of these are succumbing to either of large displacement, near-fault, and long-period earthquakes. Keeping this viewpoint, extensive research on the application of smart materials for seismic response control of buildings was attempted during the last decade. Shape Memory Alloy (SMA) with its unique properties of superelasticity and shape memory effect is one of the smart materials used for seismic control of buildings. In this paper, an exhaustive review has been compiled on the seismic control applications of SMA in buildings. Unique properties of SMA are discussed in detail and different phases of SMA along with crystal characteristics are illustrated. Consequently, various seismic control applications of SMA are discussed in terms of performance and compared with prevalent base isolators, bracings, beam-column connections, and tuned mass damper systems.

Total Instrumentations for Geotechnical Structures Using Smart Materials (Smart Material 개념을 이용한 지반구조물 정보화)

  • 송정락;전기찬
    • Proceedings of the Korean Geotechical Society Conference
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    • 2001.10c
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    • pp.79-88
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    • 2001
  • 기계, 전기, 전자, 재료, 전산공학 등은 근래에 이르러 혁명적인 발전을 거듭하고 있으며, 이에 따라 새로운 개념의 기기들이 등장하고, 토목계측분야에서도 새로운 방식 및 기기들이 등장하고 있다. 특히 최근의 Smart Material, MEM (Micro-Electro-Machine), Nano- Technology 및 통신기술들은 과거의 공상과학소설에서나 가능하였던 내용들을 실제로 가능케 하였으며, 일부 기술들은 경제성까지 갖춰 상용화되고 있다. 본 고에서는 지반공학적 관점에서 본 이러한 신기술과, 이를 이용한 지반구조물의 정보화에 대하여 살펴보았다.

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