• Journal of Sensor Science and Technology
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• v.6 no.2
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• pp.131-136
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• 1997

The ISFET(ion sensitive field effect transistor), a semiconductor ion sensor, has many advantages over conventional ion sensors. Various single-sensor type ISFET pH-meters have been developed. However, they could not be applied in fields because their performances are directly affected by the sensor condition. With only one sensor, the system could be easily damaged from environmental factors, and reliability of it is decreased. Therefore, a 4-channel PH-meter system is proposed to improve the reliability of ISFET pH-meter. It has 4 ISFETS as ion sensor, and a software which contains a new calibration and measurement algorithm appropriate to the system. The reliability of the system was proved by measuring hydrogen ion concentration in the pH standard solutions and buffer solutions.

• Journal of Sensor Science and Technology
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• v.16 no.3
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• pp.192-196
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• 2007

A fiber-optic interferometric temperature sensor is fabricated using a hollow optical fiber with 8 um air hole. This interferometric sensor for measuring temperature consists of 13 mm long hollow optical fiber whose one end is attached to the single mode fiber and the other end is cleaved. After the sensor is put in a furnace, the phase change of the sensor output signal is measured as the temperature of the furnace increases from $28^{\circ}C$ to $100^{\circ}C$. The phase change of the fiber sensor is proportional to the change of temperature and the relationship between the change of phase and temperature is approximately linear. The sensitivity of this sensor is $2.7{\;}radians/^{\circ}C$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.360-361
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• 2006

This paper describes a wire and wireless network sensor for temperature and humidity measurements. The network sensor comprises PLC(Power Line Communication) and RF transmitter(433MHz) for acquiring an internal (on-board) sensor signal, and measured data is transmitted to a main processing unit. The network sensor module is consist of MEMS sensor, 10-bit A/D converter, pre-amp., gain-amp., ADUC812 one chip processor and PLC/RF transmitting unit. The temperature and humidity sensor is based on MEMS piezoelectric membrane structure and is implemented by using dual function sensor for smart home and smart building.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.05a
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• pp.90-95
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• 1995

This paper describes the highly-sensitive Si magnetic sensor using the amplitude modulation in order to real ice the integrated magnetic sensor which to sensor a weak magnetic field. Generally, the most important two parameters in Hall IC which degrade the ability of magnetic detection are the variation of offset according to the variation of temperature and the noise of amplifiers. In this paper, we use a Hall element and compensator to reduce the offset and the nouse of amplifiers by Using amplititude modulation method.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.199-199
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• 2010

A back-gated MOSFET on silicon-on-insulator (SOI) substrate for pH sensor was investigated. We used concentrations of pH solution from 6 to 9. The fabricated back-gated MOSFET has current difference and threshold voltage shift by pH concentrations. Therefore, It can be used to simplification of conventional pH sensor.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.252-252
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• 2010

Carbon nanotubes(CNTs) have excellent electrical, mechanical and chemical properties. In this paper, the variation of charge density and resistivity in MWCNT gas sensor were defined by three Dimensional Finite element method, and an accurate description of equivalent circuit of MWCNT gas sensor was investigated.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1990.10a
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• pp.47-51
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• 1990

This paper deals with the electric field sensor. A capacitive voltage sensor is designed and manufactured for measuring the very fast transients generated by operating disconnection switch in GIS. It is certified that the voltage sensor has a good specific characteristic in high frequency domain and is able to measure the very fast transients included the harmonic components of 200[MHz].

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.59-60
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• 2006

Principals and characteristics of sensors can be easily understood by experiments based on PC. Applied experiments help further understanding sensor's wide utilization. Moreover, PC based operation makes stored sensor data to be used in Excel for various charts and graphs.

• Journal of Advanced Marine Engineering and Technology
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• v.40 no.4
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• pp.325-329
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• 2016

In this study, we investigated the feasibility of using printed Indium Tin Oxide (ITO) film as a remote sensor for Hazardous and Noxious Substances (HNS). To improve the quality of the ITO films, binder mixing ratio, Sn concentration in ITO, thermal treatment temperature, and printing process conditions were optimized. We fabricated an electrical resistance-type liquid sensor, and to confirm the sensor operation, the change in resistance in air and seawater was monitored. The change in resistance of the ITO sensor was explained in terms of reduction reaction on the surface. Further, the sensor was controlled by Arduino, and the remote data acquisition was demonstrated.

• Journal of Sensor Science and Technology
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• v.22 no.2
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• pp.162-173
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• 2013

The purpose of this paper is to classify VOC gases by emulating the characteristics found in biological olfaction. For this purpose, we propose new signal processing method based a polymeric chemical sensor array consisting of 4096 sensors which is created by NEUROCHEM project. To remove unstable sensors generated in the manufacturing process of very large scaled chemical sensor array, we used discrete wavelet transformation and cosine similarity. And, to remove the supernumerary redundancy, we proposed the method of selecting candidates of representative sensor representing sensors with similar features by Fuzzy c-means algorithm. In addition, we proposed an improved algorithm for selecting representative sensors among candidates of representative sensors to better enhance classification ability. However, Classification for very large scaled sensor array has a great deal of time in process of learning because many sensors are used for learning though a redundancy is removed. Throughout experimental trials for classification, we confirmed the proposed method have an outstanding classification ability, at transient state as well as steady state.