• Journal of the Institute of Convergence Signal Processing
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• v.9 no.3
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• pp.219-223
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• 2008

The dissolved oxygen (DO) sensors were fabricated by screen printing method, and potable dissolved oxygen measurement system was fabricated for low cost products. The fabricated sensors had high current change and fast response according to dissolved oxygen concentrations in the applied voltage of 0.7 V. The DO measurement system was consisted of MCV, amplifier, filter, power supply and display. DO concentrations were programed to display as digital percentages by converting the analog value. It is expected that the fabricated DO measurement system can replace the expensive commercial DO meter, because it reveals the high accuracy of ${\pm}0.5%$ to the standard solution and the response time of about 100 sec like the commercial DO meter.

• Journal of Sensor Science and Technology
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• v.14 no.6
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• pp.444-454
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• 2005

The IEEE 1451.4 standards defines an architectural model for interfacing smart transducers for sensors & actuators. This standard allows analogue transducers to communicate their identification and calibration data in a digital format. A digital format is called the TEDS (transducer electronic data sheet). However, the standard template TEDS of IEEE 1451.4 do not supports sensors to use in electronic tongue system, such as arrayed-potentiometric and voltametric sensors. In this paper, a solution to standardize sensors for E-Tongue (electronic tongue) and electronic tongue systems is presented.

• Journal of Sensor Science and Technology
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• v.18 no.3
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• pp.217-221
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• 2009

Different methods of material engineering, used for improvement of solid state gas sensors parameters are reviewed in this report. The wide possibilities of material engineering in optimization of gas sensing properties were demonstrated on the example of $SnO_2,\;TiO_2\;and\;In_2O_3$-based sensors.

• Proceedings of the KIEE Conference
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• 2005.10b
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• pp.123-126
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• 2005

The IEEE 1451.4 standards defines an architectural model for interfacing smart transducers for sensors & actuators. This standard allows analogue transducers to communicate their identification and calibration data in a digital format. A digital format is called TEDS(transducer electronic data sheet). However, the standard template of IEEE 1451.4 TEDS do not supports gas sensors to use in electronic nose system, such as array sensors. In this paper, a solution to standardize sensors for electronic nose systems is presented.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.43 no.1 s.307
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• pp.21-30
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• 2006

The IEEE 1451.4 standards defines an architectural model for interfacing smart transducers for sensors & actuators. This standard allows analogue transducers to communicate their identification and calibration data in a digital format. A digital format is called TEDS(transducer electronic data sheet). However, the standard template of IEEE 1451.4 TEDS do not supports gas sensors to use in electronic nose system such as may sensors. In this paper, a solution to standardize sensors for electronic nose systems is presented.

• International journal of advanced smart convergence
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• v.3 no.2
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• pp.14-17
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• 2014

Precision agriculture relies on information technology, whose precondition is providing real-time and accurate information. It depends on various kinds of advanced sensors, such as environmental temperature and humidity, wind speed, light intensity, and other types of sensors. Currently, it is a hot topic how to collect accurate information, the main raw data for agricultural experts, monitored by these sensors timely. Most existing work in WSNs addresses their fundamental challenges, including power supply, limited memory, processing power and communication bandwidth and focuses entirely on their operating system and networking protocol design and implementation. However, it is not easy to find the self-localization capability of wireless sensor networks. Because of constraints on the cost and size of sensors, energy consumption, implementation environment and the deployment of sensors, most sensors do not know their locations. This paper provides maximum likelihood estimators for sensor location estimation when observations are time-of arrival (TOA) range measurement.

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

• Journal of Sensor Science and Technology
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• v.32 no.1
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• pp.55-61
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• 2023

The objective of this study is to determine the concentrations of mixed gases by establishing a diagnosis method of a transformer using tunable-wavelength optical infrared sensors. Absorption of infrared light by methane, acetylene, and ethylene gases injected is measured from the outputs of the infrared sensors. Regression analysis equations of the gas concentrations are acquired from their respective measured absorption. The obtained concentrations are as follows: -3-9 % errors above 600 ppm(methane), 3 % errors above 1200 ppm(acetylene), and 10 % errors above 500 ppm(ethylene). The concentration inference equations obtained using the individual gases are applicable when the absorption wavelength bands do not overlap. The results of the fault analysis of a transformer using the Duval triangle method and the tunable infrared gas sensors are as follows: temperature faults with -1-1% errors and energy faults with -7-7 % errors.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.1334-1337
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• 2005

Orange-yellow phosphor has been synthesized by solid-state method for inorganic EL devices. Zinc sulfide is used as host material for the phosphor and the phosphor consists of copper and manganese as activators. The dependence of the photoluminescence (PL) and electroluminescence(EL) properties on the copper and manganese concentrations has been investigated.

• Structural Monitoring and Maintenance
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• v.2 no.2
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• pp.145-164
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• 2015

Bridge scour is the predominant cause of overwater bridge failures in North America and around the world. Several sensing systems have been developed over the years to detect the extent of scour so that preventative actions can be performed in a timely manner. These sensing systems have drawbacks, such as signal inaccuracy and discontinuity, installation difficulty, and high cost. Therefore, attempts to develop more efficient monitoring schemes continue. In this study, the viability of using optical dissolved oxygen (DO) probes for monitoring scour depths was explored. DO levels are very low in streambed sediments, as compared to the standard level of oxygen in flowing water. Therefore, scour depths can be determined by installing sensors to monitor DO levels at various depths along the buried length of a bridge pier or abutment. The measured DO is negligible when a sensor is buried but would increase significantly once scour occurs and exposes the sensor to flowing water. A set of experiments was conducted in which four dissolved oxygen probes were embedded at different soil depths in the vicinity of a mock bridge pier inside a laboratory flume simulating scour conditions. The results confirmed that DO levels jumped drastically when sensors became exposed during scour hole evolution, thereby providing discrete measurements of the maximum scour depth. Moreover, the DO probes could detect any subsequent refilling of the scour hole through the deposition of sediments. The effect of soil permeability on the sensing response time was also investigated.