• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1427-1428
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• 2015

MEMS(Micro Electro-mechanical System) are getting attention as promising industry in the 21st century. Car air bags, acceleration sensors, and medical, information appliances are being actively applied in MEMS. This paper suggest the electrical electrodes of brain signal applied MEMS model and the prototype design for EEG signal amplification circuit. Also, we suggest an independent BCI(Brain Computer Interface) system with brain electrical signal of electrode models and wireless communication platform.

• Proceedings of the KIEE Conference
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• 1999.11d
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• pp.1081-1083
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• 1999

The capacitive coupling technique has been used as conventional method for PD detection on the power cable line. Recently, however PD measurement using by high frequency is known to have an excellent sensitivity comparison with low frequency on-site. In this paper, the high frequency characteristic of two type of metal foil sensor was studied and the technique was proved to be more effective diagnostic method than conventional method for qualification of EHV cable and accessories.

• Journal of Biosystems Engineering
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• v.30 no.4 s.111
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• pp.249-253
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• 2005

This study was carried out to develop enzyme biosensor for lactic acid bacteria. Lactic acids produced by lactic acid bacteria (LAB) was measured and good correlation $R^2=0.98$ between LAB count and lactic acids concentration was found. Hydrogen ion produced by L-lactate dehydrogenase (L-LDH) was measured by a potentiometer. Glutamic-pyruvic transminase (GPT) was used for eliminating inhibitor in the reaction. Polyacrylamide gel was used for immobilizing matrix of the sensor. The biosensor was tested and showed good feasibility with $R^2=0.99$ on validation.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.305-305
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• 2009

The carbon nano-structured materials could be applied to the fields of advanced fillers, templates, electrode materials, sensor, storage, and absorption materials. The polyacrylonitrile (PAN) based carbon nano-particles provide the remarkable properties of high specific surface area, large pore volume, chemical inertness, and good mechanical stability. In this study, well-defined carbon nano-particles were obtained through pyrolysis of polyacrylonitrile based particles. The precursor nano-particles were prepared by modified aqueous dispersion polymerization using hydrophilic poly(vinyl alcohol) in a water/ N,N-dimethylformamide mixture media. Synthesized precursor nanoparticles have relatively monodisperse particles ranging 80 ~ 250nm. Stable spherical particles are obtained without coagulum or secondary particles in our system. The characteristic of the carbon nanoparticles were investigated in terms of surface area, morphology, and size distribution.

• Food Science and Biotechnology
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• v.14 no.6
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• pp.743-746
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• 2005

A dipstick-type immunochemical biosensor for the detection of the organophosphorus insecticide fenthion was developed using a screen-printed electrode system as an amperometric transducer with polyclonal antibodies against fenthion as a bioreceptor. The assay of the biosensor involved competition between the pesticide in the sample and pesticide-glucose oxidase conjugate for binding to the antibody immobilized on the membrane. This was followed by measurement of the activity of the bound enzyme by the supply of the enzyme substrate (glucose) and amperometric determination of the enzyme reaction product ($H_2O_2$). The activity of the bound enzyme was inversely proportional to the concentration of pesticide. The optimized sensor system showed a linear response against the logarithm of the pesticide concentration ranging from $10^{-2}$ to $10^3\;{\mu}g/L$.

• Analytical Science and Technology
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• v.14 no.3
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• pp.286-289
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• 2001

The effect of pH and the substrate concentration on the sensing ability of the chicken peroxidase enzyme electrode was examined quanititatively. Using the new Michaelis-Menten equation, to which pH concept was introduced, enabled to calculate all kinds of dissociation constant related to chicken peroxidase and subsequently to determine the optimum pH of the sensor.

• Journal of Sensor Science and Technology
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• v.21 no.5
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• pp.385-388
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• 2012

This paper describes the synthesis and characterization of graphene by RTA process. Amorphous 3C-SiC were deposited using APCVD for carbon source and Ni layer were employed for transition layer. Various parameters of the ramping speed, the annealing time and the cooling speed are evaluated for the optimized combination allowed for the reproducible fabrication of graphene using 3C-SiC thin film. For analysis of crystalline Raman spectra was employed. Transferred graphene shows a high IG/ID ratio of 2.73. SEM and TEM images show the optical transparency and 6 carbon network, respectively. Au electrode deposited on the transferred graphene shows linear I-V curve and its resistance is 358 ${\Omega}$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1996.11a
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• pp.393-396
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• 1996

The electrical characteristics of stearic acid LB films far the horizontal direction were investigated to develop the gab sensor using LB films. $\pi$ -A isotherm was measured to transfer stearic acid on slide glass substrate and surface pressure for optimal deposition was 25[dyne/cm]. The deposition status of stearic acid LB films was verified by the measurement of capacitance which was increased with the number of layers. The thickness of electrode was estimated about 1000 by the I-V characteristics far the horizontal direction. The Conductivity of stearic acid LB films for horizontal direction was 10$^{-8}$ [S/cm] that mean like semiconductor.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.49 no.2
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• pp.82-86
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• 2000

Humidity sensors using $TiO_2$ thin films were fabricated on the multi-electrode device by Sol-Gel method and their wettability, surface potential decays and humidity sensing characteristics were investigated. Contact angle of thin films was $28^{\cic}\;at\; 400^{\circ}C$ and surface potential decayed rapidly at $400^{\circ}C$. The specimen showed best humidity sensing characteristics at $400^{\circ}C$. From the results, they were confirmed that humidity sensing characteristics of thin films have connection with contact angle and surface potential decays.

• Proceedings of the KIEE Conference
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• 2000.11c
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• pp.513-515
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• 2000

In this paper, new Partial Discharge (PD) detection technique using Pockels-cell was proposed. For this purpose, PD was generated from needle-plane electrode in air and detected by optical measuring system using Pockets cell, based on Mach-Zehnder interferometer, consisting of He-Ne laser, single mode optical fiber, 50/50 beam splitter and photo detector. We show the characteristic of the proto-type sensor for the corona discharge.