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1	The preparation and properties of the pH-ISFET with amorphous PbTiO3 membrane by the sol-gel technique Lu, Chun-Te 04 July 2001 (has links) Ion-sensitive field effect transistors (ISFET's) have many advantages than the conventional ion selective electrode. Small size, fast response and compatible with conventional IC technologies were the most important advantages. The general structure of ISFET was the same with MOSFET, but the main difference is that the metal gate in MOSFET was replaced by reference electrode/electrolyte/insulator(ionic sensor membrane) structure in ISFET. The insulator surface will suffer the change of potential as the is sample immersed into electrolyte, by which, we can measure the pH or other ionic concentration. In this thesis the amorphous lead titanate (a-PbTiO3) thin film was prepared by sol-gel method to be the sensor gate of ISFET. The lead titanate thin films were deposited on SiO2(1000Å)/p-Si substrates, and the EIS structure was obtained. The flat-band voltage(£GVBF) can be shifted by C-V measurement. The optimum conditions were found that the firing temperature was about 4000C and thin film thickness was about 0.5 EIS structure sol-gel amorphous lead titanate hysteresis response stable time drift ISFET
2	Estimation over heterogeneous sensor networks Sandberg, Henrik, Rabi, Maben, Skoglund, Mikael, Johansson, Karl Henrik January 2008 (has links) Design trade-offs between estimation performance, processing delay and communication cost for a sensor scheduling problem is discussed. We consider a heterogeneous sensor network with two types of sensors: the first type has low-quality measurements, small processing delay and a light communication cost, while the second type is of high quality, but imposes a large processing delay and a high communication cost. Such a heterogeneous sensor network is common in applications, where for instance in a localization system the poor sensor can be an ultrasound sensor while the more powerful sensor can be a camera. Using a time-periodic Kalman filter, we show how one can find an optimal schedule of the sensor communication. One can significantly improve estimation quality by only using the expensive sensor rarely. We also demonstrate how simple sensor switching rules based on the Riccati equation drives the filter into a stable time-periodic Kalman filter. ï¿œ 2008 IEEE. / <p>QC 20110224</p> Communication costs Design trade-offs Estimation performance Estimation qualities Heterogeneous sensor networks High qualities Localization systems Low qualities Optimal schedules Processing delays Sensor communications Sensor scheduling Stable time Switching rules Ultrasound sensors Communication Control theory Estimation Heterogeneous networks Kalman filters Riccati equations Sensor networks Computer science Datavetenskap

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The preparation and properties of the pH-ISFET with amorphous PbTiO3 membrane by the sol-gel technique

Estimation over heterogeneous sensor networks