• Proceedings of the KIEE Conference
• /
• 2008.07a
• /
• pp.1468-1469
• /
• 2008

기상관측 분야에서는 풍속센서의 소형화 요구가 커지고 있어 Air flow sensor를 이용한 MEMS(Micro Electro Mechanical System) 풍향 풍속센서의 응용연구가 활발하다. MEMS 풍향 풍속 센서는 수 mm 크기를 가지면서도 바람의 세기와 함께 방향을 측정하여야 하는데, 센서 칩이 노출되어 있어 외부환경으로부터 영향을 받기 때문에 센서소자의 내오염성과 내구성 확보가 중요하다. 따라서 본 연구에서는 절연막으로 비점착성의 테프론 막을 적용하여 외부환경으로부터 영향을 줄일 수 있는 열감지 방식의 MEMS 풍향 풍속 센서 칩을 제작하였다. 테프론 코팅막을 이용한 풍향 풍속 센서는 0.1m/s의 resolution을 가지며, 최대 15m/s까지 측정이 가능하여, 오염에 강하고 발수성을 센서를 제작하였다.

• Journal of KIISE:Computing Practices and Letters
• /
• v.14 no.1
• /
• pp.31-39
• /
• 2008

Sensor Node OS should support unified API and efficient sensor device management system to overcome the diversity of sensors and actuators. However, conventional OSs like Tiny-OS and Nano-Q+ do not. In this paper, we propose a sensor device driver management system that present application programmers with unified API and easy deployment of sensors. When a sensor is deployed in our device management system, the device driver is downloaded. This scheme differs from traditional OS like SOS in that only sensor device driver is downloaded, not the whole application image. We designed and implemented the system into Nano-Q+. We described the comparison with other OSs and showed that our system obtains the considerable speedup of downloading.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2009.05a
• /
• pp.627-630
• /
• 2009

The combination of the marine use various multi sensor surveillance system technology with the development of servo motion control algorithm and gyro sensor in six freedom motion is implemented to analyze the movement response. The stabilization of the motion control is developed and Nano driving Precision Pan-Tilt/Gimbal system is obtained from the security positioning cameras with ultra high speed device is used to carry out the exact behavior of the device. The exact behavior will be used to make a essential equipment. Finally the development of the Nano Driving Multi Sensor, Nano of Surveillance System Driving Precision Pan-Tilt/Gimbal optimal design and production, 3-aix Gyro Sensor based with Servo Motion Control algorithm development, Image trace video software and hardware tracking the development is organized and discuss in details. The development of the equipment and the system integration are fully experimented and verified.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.24 no.3
• /
• pp.247-252
• /
• 2014

This paper presents a novel impact sensor which can be fabricated with smart paint made of grapheme. This smart nano paint can be easily installed on structures using a spray-on technique and that can make the sensor low cost and practical. The graphene effectively improves the piezoresistivity of the smart paint and that is available to achieve sensitive impact sensor with high gauge factor. The nano smart-paint can detect sufficient impact to cover the damaged energy range of the composite around 1~3J. The voltage outputs from the sprayed paints show fairly linear responses after signal processing. The impact makes deformation of the structure and it brings change of piezoresistivity of the paint and those converts into voltage output consequently by means of a simple signal processing system. The nano smart paint is lightweight and easily applied to the structural surface, and there is no stress concentration. The nano smart paint is expected to be a cost effective and sensitive multi-functional sensor for composites and other damage monitoring applications in the field of structural health monitoring.

• Journal of Sensor Science and Technology
• /
• v.23 no.2
• /
• pp.110-113
• /
• 2014

In this paper, we propose and demonstrate a Fabry-Perot interferometer (FPI) optical fiber tip sensor fabricated by a blade-sawing technique using a fiber optic patch cord for high-resolution temperature measurement. The sensor head consists of a short air FP cavity near the tip of a single-mode fiber patch cord tip. The temperature which we can measure is determined through a phase variation of the interference fringes in the reflective spectrum of the sensor. The fiber optic FPI sensor in this work can monitor the environmental temperature very accurately from 40 to $120^{\circ}C$. As a result, the temperature sensitivity is obtained as $38.2pm/^{\circ}C$.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.13 no.9
• /
• pp.1928-1934
• /
• 2009

This paper proposes a power management scheme for sensor nodes in wireless sensor networks based on sensor node operating system supporting the sensor transparency, which can turn off the sensors when the MCU is in sleep mode. We classify the sensors in two types, that is, event sensors and polling sensors, to be able to decide whether the sensor is a type of sensors whose power supply can be turned off or not, and we design a new scheduler to support recognition of those different types of sensors. Implementing and evaluation of the scheduler and the power manager supporting sensor transparency are shown based on Nano-Q+.

• Journal of Sensor Science and Technology
• /
• v.25 no.4
• /
• pp.280-284
• /
• 2016

For an arc-flash protection system, the selection of arc-flash sensor in implementation is largely dependent on the coverage area and the spatial resolution. Typically, a point sensor is used to accurately measure an arc event within a very narrow region; whereas, a loop or a line sensor can cover several electrical compartment at the same time, but with a poor resolution. In this work, a novel scheme for an arc-flash sensor was developed by making use of the transmission loss of plastic optical fibers (POFs) to cover a broad range with a high spatial resolution. By relating the amplitude ratio of the arc-signals at the ends of the POF with the arc-location, arc events could be located with a resolution of ~5 cm within a spatial range of 10 m, which has not been reported yet.

• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 2005.05a
• /
• pp.237-240
• /
• 2005

The demand of micro electrical mechanical system (MEMS) bio/chemical sensor is rapidly increasing. To prevent the contamination of sensing area, a filtration system is required in on-chip total analyzing MEMS bio/chemical sensor. A nano-filter was mainly applied in some application detecting submicron feature size bio/chemical products such as bacteria, fungi and so on. We suggested a simple nano-filter fabrication process based on replication process. The mother pattern was fabricated by holographic lithography and reactive ion etching process, and the replication process was carried out using polymer mold and UV-imprinting process. Finally the nano-filter is obtained after removing the replicated part of metal deposited replica. In this study, as a practical example of the suggested process, a nano-dot array was replicated to fabricate nano-filter fur bacteria sensor application.

• Journal of the Korean Society for Precision Engineering
• /
• v.25 no.11
• /
• pp.7-14
• /
• 2008

• Journal of Sensor Science and Technology
• /
• v.14 no.5
• /
• pp.302-307
• /
• 2005

Precision displacement of less than a few nm resolution was measured in real-time using fiber optic EFPI sensor. The novel method for real-time processing of analyzing EFPI output signal was developed and verified. Linearity in the mean values of interferometric light intensity among adjacent fringes was shown and verified the sinusoidal approximation algorithm that estimates past and coming fringe values. Real-time signal processing program was developed and the intensity signal of the EFPI sensor was transformed to the phase shift with this program. The resolution below $0.36{\sim}8.6$ nm in the displacement range of $0{\sim}300{\mu}m$ was obtained. The nano-positioner with a piezoelectric actuator and the EFPI sensor system was designed and tested. The positioner successfully reached to the desired destination within 1 nm accuracy.