• Journal of the Korean Society for Precision Engineering
• /
• v.21 no.12
• /
• pp.7-12
• /
• 2004

• Journal of the Optical Society of Korea
• /
• v.17 no.3
• /
• pp.231-236
• /
• 2013

We present both theoretically and experimentally the thermo-optic characteristics of micro-structured optical fiber (MOF) filled with mixed liquid. The performance of MOF depends on the efficient interaction between the fundamental mode of the transmitted light wave and the tunable thermo-optic materials in the cladding. The numerical simulation indicates that the confinement loss of MOF presents higher temperature dependence with higher air-filling ratios $d/{\Lambda}$, longer incident wavelength and fewer air holes in the cladding. For the 4cm liquid-filled grapefruit MOF, we demonstrate from experiments that different proportions of solutions lead to tunable temperature sensitive ranges. The insertion loss and the extinction ratio are 3~4 dB and approximate 20 dB, respectively. The proposed liquid-filling MOF will be developed as thermo-optic sensor, attenuator or optical switch with the advantages of simple structure, compact configuration and easy fabrication.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.16 no.11 s.116
• /
• pp.1172-1178
• /
• 2006

Measurement of blade strain with sensors directly installed on the blade has one critical issue, how to send the sensor signal to the ground. Strain-gauges have been dominantly used to directly measure stress of a blade and either a slip ring or a telemetry system has to be used to send measured signal to the ground. However, both systems have many inherent problems and sometimes very severe limitations to be practically used. In this paper, new on-line strain monitoring method using. FBG(Fiber Bragg Grating) sensors and a beam coupler is introduced. Measurement of rotor stress using FBG sensors is nothing new, but unlike other system which installs all necessary instruments on the rotor and use telemetry system to send data to the ground, this system makes use of light's unique characteristic - light travels through space. In this new approach, single optical fiber with many FBG sensors is installed on the blade and all other necessary instruments can be installed at ground thereby giving tremendous advantages over slip ring or telemetry system. A reference sensor is also introduced to compensate the beam coupler's transmission loss change due to rotation. The suggested system's good performance is demonstrated with experiments.

• Smart Structures and Systems
• /
• v.6 no.9
• /
• pp.1007-1023
• /
• 2010

This paper describes the development and evaluation of an innovative TDR distributed moisture sensor. This sensor features advantages of being responsive to the spatial variations of the soil moisture content. The geometry design of the sensor makes it rugged for field installation. Good linear calibration is obtained between the sensor measured dielectric constant and soil physical properties. Simulations by the finite element method (FEM) are conducted to assist the design of this sensor and to determine the effective sampling range. Compared with conventional types of moisture sensor, which only makes point measurement, this sensor possesses distributed moisture sensing capability. This new sensor is not only easy to install, but also measures moisture distribution with much lower cost. This new sensor holds promise to significantly improve the current field instruments. It will be a useful tool to help study the influence of a variety of moisture-related phenomena on infrastructure performance.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.30 no.3
• /
• pp.182-188
• /
• 1994

In recent years, navigational and fisheries instruments are rapidly advancing. Especially data processing. data transferring and data interchange throughout the digital signals has been in high progress. Even though the ship's heading is also provided by a gyro-compass, an electro-magnetic compass studying by us currently is easy to issue adequate data to instruments requiring the information for the ship's heading. especially in small fishing boats. As the main element of the electro-magnetic compass is a three-axis magnetic sensors, the developing of the high performance sensor is in highly necessity in the beginning. This paper describes on the development of electro-magnetic compass of three-axis fixed type by using three-axis detection new type magnetic sensor without gimbals. even though usual electro-magnetic compass have to need necessarily a gimbal system in order to keep horizontal condition of the compass.

• Journal of Sensor Science and Technology
• /
• v.21 no.2
• /
• pp.127-134
• /
• 2012

Stroke patients must do the rehabilitation exercise to recover their fingers' function using a rehabilitation robot. But the rehabilitation robots mostly have not the force sensors to control the applied force to each finger. Thus, in this paper, the development of a force sensor for thumb rehabilitation robot and four two-axis force sensors for four-finger rehabilitation robot were developed. The force sensor and four two-axis force sensors could be used to measure the applied force to each finger, and the forces could be used to control the applied forces to each sensor in rehabilitation exercise using in the rehabilitation robot. The developed sensors have non-linearlity error of less than 0.05 %, repeatability error of less than 0.03 %, and the interference error of two-axis force sensor is less than 0.2 %.

• IEMEK Journal of Embedded Systems and Applications
• /
• v.7 no.5
• /
• pp.219-226
• /
• 2012

The rises of the life index quality together with the medical technology improvement lead to a longer life expectancy. Then a better health care program, especially for elderly, is needed. The common health problems facing those senior citizens are changed from acute diseases to chronic diseases, such as diabetes, hypertension. Then u-Health takes center stage in medical industry. Although u- Health medical device manufacturers have been improving their instruments, these instruments still rely on proprietary technologies without fixed platform. Even if the interface has been provided by the manufacturer, there is no widely-accepted uniform data model to access data of various u-Health devices. IEEE 11073 is a standard attempting to unify the interfaces of all medical devices. In this paper we have proposed a conversion software platform that assures interoperability among medical devices for ubiquitous sensor network. This module uses in order to develop a standard platform of medical system.

• Journal of the Microelectronics and Packaging Society
• /
• v.23 no.4
• /
• pp.49-55
• /
• 2016

Nowadays there are magnetic sensors in a wide variety of equipment such as computers, cars, airplanes, medical and industrial instruments. In many of these applications the magnetic sensors offer safe and non-invasive means of detection and are more reliable than other technologies. The electric current in a conductor generates a magnetic field detected by this type of sensor. This work aims to define a package dedicated to an electrical current sensor using a MTJ (Magnetic Tunnel Junction) as a sensing device. Four different proposals of packaging, three variations of the chip on board (CoB) package type and one variation of the thin small outline package (TSOP) were analyzed by COMSOL modeling software by simulating a brad range of current injection. The results obtained from the thermal and magnetic analysis has proven to be very important for package improvements, specially for heat dissipation performance.

• Advances in nano research
• /
• v.14 no.5
• /
• pp.399-407
• /
• 2023

As Sensor plays an important part in day-to-day life. Sensors are used almost in each domain wherein humans are not able to sense or measure some parameters. Say from sensing a real-time activity of a person to sensing the tiny molecules of any gas or structures. Now sensors combined with advanced fabrication techniques with nanotechnology can be said as a game-changing combination. As the modern world is evolving every minute, the size of the components, instruments, and different equipment is shrinking rapidly. For example, the sensor or any other element which was used 10 years ago is reduced up to 5 times its original size and all of this is possible because of continuous advancement done in the manufacturing and fabrication techniques that are being used nowadays. Apart from this, it is not necessary that the term nano should only justify the size of the sensor. Nanotechnologically fabricated, refers to a sensor or any other element which may be large enough as compared to the regular one but they may be structured using some nano-particles.

• The Journal of Korean Institute for Practical Engineering Education
• /
• v.3 no.1
• /
• pp.76-83
• /
• 2011

In this paper we suggest an effective teaching plan for measurement engineering by utilizing the NI-ELVIS(National Instrument Educational Laboratory Virtual Instrumentation Suite). ELVIS is a development platform for LabVIEW-based design and prototyping environment. It consists of LabVIEW-based virtual instruments, a multifunctional data acquisition device, and a custom-designed benchtop workstation and prototyping board. Therefore it can replace the expensive instruments for the effective education in the area of electrical engineering. This platform can be applicable for the sensor instrumentation engineering study, though it is a multidisciplinary learning including electrical engineering, sensor technology, signal processing and data analysis. We hope this approach can be used for the other educational area related the electrical experimental education.