• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07b
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• pp.814-817
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• 2003

As additive Pt of a little to $SnO_2$ that gas sensing property is superior oxide-semiconductor material to fabricate gas sensor that operation is possible at room temperature and fabricated ceramic gas sensing devices. And, the change amount and sintering temperature of addition material investigated gas sensitivity by change of operation temperature, humidity relativity, Long-term stability and hysteresis. And achieved SEM and XRD analysis for characteristics searching examination of devices.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.2 no.3
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• pp.13-19
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• 2003

The high speed machining technology has been improved remarkably in die/mold industry with the growth of parts and materials industries. Though the spindle speed of machine tool increases, the condition monitoring techniques of the machine tool, tool and workpiece in high speed machining ate incomplete. In tins study, efficient sensing technology in high speed machining is suggested by observing the characteristics of cutting force, gap sensor and accelerometer signal also, machinability of high-speed machining is experimentally evaluated sensing technique to monitor the machine tool and machining conditions was performed.

• Journal of Sensor Science and Technology
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• v.19 no.2
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• pp.67-86
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• 2010

Hydrogen is emerging as clean fuel and important industrial raw materials. The hydrogen gas is not sensed by the human olfactory system, But the combustion characteristics of hydrogen is that the ignition is very easy, the propagation speed of the flame is very fast and explosion limits is a wide range of 4 %~75 %. Therefore it is extremely in danger, and the need for its leakage detection technologies is especially important in places such as a production, transportation, storage and usage. The hydrogen sensors are classified with ceramic type, semiconductor type, optical type, electrochemical type and so on. Hydrogen sensors and their technologies are reviewed in detail for materials, fabrication process, sensing characteristics, good point and faults, and production and utilization of sensors be discussed.

• Korean Journal of Remote Sensing
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• v.28 no.6
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• pp.671-682
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• 2012

Strong backscattering features from high-resolution Synthetic Aperture Rader (SAR) image provide useful information to analyze earth surface characteristics such as man-made objects in urban areas. The SAR image has, however, some limitations on description of detail information in urban areas compared to optical images. In this paper, we propose a new classification method using a fused SAR and Electro-Optical (EO) image, which provides more informative classification result than that of a single-sensor SAR image classification. The experimental results showed that the proposed method achieved successful results in combination of the SAR image classification and EO image characteristics.

• Proceedings of the KSRS Conference
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• 1998.09a
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• pp.218-224
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• 1998

The coefficients of variation obtained from three typical vegetation indices of eight levels of multi-spatial resolution images in urban areas were employed to identify the optimum spatial resolution in terms of maintaining information quality. These multi-spatial resolution images were prepared by degrading 1 meter simulated, 16 meter ADEOS/AVNIR, and 30 meter Landsat-TM images. Normalized Difference Vegetation Index (NDVI), Perpendicular Vegetation Index (PVI) and Soil Adjusted Ratio Vegetation Index (SARVI) were applied to reduce data redundancy and compare the characteristics of multi-spatial resolution image of vegetation indices. The threshold point on the curve of the coefficient of variation was defined as the optimum resolution level for the analysis with multi-spatial resolution image sets. Also, the results from the image segmentation approach of region growing to extract man-made features were compared with these multi-spatial resolution image sets.

• Journal of Sensor Science and Technology
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• v.10 no.2
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• pp.86-90
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• 2001

A pyroelectric senior using P(VDF/TrFE) film for sensing materials has been fabricated and evaluated with other commercial pyroelectric sensors that use ceramic materials for sensing. The device was mounted in a TO-5 housing to detect infrared light of $5.5{\sim}14\;{\mu}m$ wavelength. The NEP (noise equivalent power) and specific detectivity $D^*$ of the device were $2.13{\times}10^{-8}\;W$ and $9.37{\times}10^6\;cm/w$ respectively under emission energy of $13\;{\mu}W/cm^2$ respectively. These result shows a better characteristics than other commercial pyroelectric sensors NEP $8.08{\times}10^{-7}\;W$ and $D^*$ $2.47{\times}10^5\;cm/w$.

• Journal of Sensor Science and Technology
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• v.15 no.6
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• pp.457-461
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• 2006

To use the porous silicon as gas sensors, we made the MOPS structure from the porous silicon with Al evaporation and investigated the sensing characteristic of ethanol. When the MOPS structure is in contact with ethanol gas, the maximum peak of PL changes and it return to original intensity without contact. The MOPS structure had response time 0.78s and recovery time 4.13s when it is in contact with ethanol, which satisfied the required sensor standards. Further complimentary researches, however, are required to investigate the contact mechanism between MOPS structure and ethanol and to solve the surface contamination problem.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.52 no.10
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• pp.475-483
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• 2003

In this paper, dynamic characteristics of the magnetic flux leakage(MFL) type non-destructive testing(NDT) are analyzed. Effects of a sensor speed in MFL PIG system and remanent magnetization of the gas pipeline are analyzed by using 3 dimensional nonlinear finite element analysis including eddy current and hysteresis characteristics. Results show that the speed of the sensor reduces the magnitude of the sensing signals where as the hysteresis of the pipeline distorts the sensing signals.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.11a
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• pp.464-467
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• 2002

$TiO_{2}-Co_{3}O_{4}$ humidity sensors were fabricated by conventional ceramic process and their humid sensing characteristics were investigated. The sample which was added 10wt% $Co_{3}O_{4}$ and heat-treated $1200^{\circ}C$ showed the highest sensitivity to humidity changes and improved a linearity. As $Co_{3}O_{4}$ content was increasing, the sensor consists a uniform pore distribution and grain in the surface. This was analyzed by SEM photographs.

• Proceedings of the KIEE Conference
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• 1997.07d
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• pp.1531-1533
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• 1997

We prepared polyimide film by electrophoretic deposition onto glass film as a sensing materials of humidity, and treated with plasma discharging as a function of discharging power to improve performance of the sensor. Then evaluated the characteristics of polyimide on humidity.