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Abstract: Li⁺ ion conducting Li₃PO₄ thin film electrolytes with thickness 300nm, 650nm and1.2μm were deposited on Al₂O₃ substrate at room temperature by thermal evaporation method.Reference and sensing electrodes were printed on Au interfaces by conventional screen printingtechnique. The overall dimension of the sensor was 3 x 3 mm and of electrodes were 1 x 1.5 mmeach. The fabricated solid state potentiometric CO₂ sensors of type: CO₂, O₂, Au, Li₂TiO₃-TiO₂ / Li₃PO₄ / Li₂CO₃, Au, CO₂, O₂ have been investigated for CO₂ sensing properties. Theelectromotive force (emf) and δemf/dec values of the sensors are dependent on the thickness ofthe electrolyte film. 1.2μm thickness deposited sensor has shown good sensing behavior than thesensors with less thickness. The δemf values of the sensor are linearly increased up to 460^oCoperating temperature and became stable above 460^oC. Between 460-500^oC temperatures regionthe sensor has reached an equilibrium state and the experimentally obtained δemf values areabout 80% of the theoretically calculated values. A Nernst’s slope of -61mV/decade has beenobtained between 250 to 5000 ppm of CO₂ concentration at 500^oC temperature. The sensor issuitable for ease of mass production in view of its miniaturization and cost effectiveness aftersome further improvement.

Abstract: In this communication we review selected experiments involving the use ofcarbon paste electrodes (CPEs) to monitor and measure brain tissue O₂ levels in awakefreely-moving animals. Simultaneous measurements of rCBF were performed using the H₂clearance technique. Voltammetric techniques used include both differential pulse (O₂) andconstant potential amperometry (rCBF). Mild hypoxia and hyperoxia produced rapidchanges (decrease and increase respectively) in the in vivo O₂ signal. Neuronal activation(tail pinch and stimulated grooming) produced similar increases in both O₂ and rCBFindicating that CPE O₂ currents provide an index of increases in rCBF when such increasesexceed O₂ utilization. Saline injection produced a transient increase in the O₂ signal whilechloral hydrate produced slower more long-lasting changes that accompanied the behavioralchanges associated with anaesthesia. Acetazolamide increased O₂ levels through an increasein rCBF.

Abstract: In the present paper, in order to estimate the response of both a wheel speedsensor and an accelerometer placed in a car under performance tests, robust and optimalmultivariable estimation techniques are used. In this case, the disturbances and noisescorrupting the relevant information coming from the sensors’ outputs are so dangerous thattheir negative influence on the electrical systems impoverish the general performance of thecar. In short, the solution to this problem is a safety related problem that deserves our fullattention. Therefore, in order to diminish the negative effects of the disturbances and noiseson the car’s electrical and electromechanical systems, an optimum observer is used. Theexperimental results show a satisfactory improvement in the signal-to-noise ratio of therelevant signals and demonstrate the importance of the fusion of several intelligent sensordesign techniques when designing the intelligent sensors that today’s cars need.