This paper is focused on a novel design of stepped diaphragm for MEMS capacitive pressure sensor used in tire pressure monitoring system. The structure of sensor diaphragm plays a key role for determining the sensitivity of the sensor and the non-linearity of the output.First the structures of two capacitive pressure sensors with clamped square flatdiaphragms, with different thicknesses are inv...

Wireless sensor networks (WSNs) have many applications in the areas of commercial, military and environmental requirements. Regarding the deployment of low cost sensor nodes with restricted energy resources, these networks face a lot of security challenges. A basic approach for preparing a secure wireless communication in WSNs, is to propose an efficient cryptographic key management protocol be...

cupric oxide nanostructures were synthesized via a simple reaction between copper nitrate and sodium hydroxide using a sonochemical-assisted method. the synthesized cuo was then characterized using x-ray diffraction, scanning electron microscopy, transmission electron microscopy, fourier transform infrared, ultraviolet-visible and photoluminescence spectroscopy. our studies show that the cuo na...

The design and optimization of nanostructure-based surface acoustic wave (SAW) gas sensor is analyzed based on TiO2 sensing layer and modified electrode dimensions. The sensitivity of the gas sensor depends upon the type of sensing layer used and active surface area obtained by varying the aspect ratio. The performance of the sensor is observed from 0.1ppm to 100ppm concentration of ...

wireless sensor networks (wsns) consist of a large number of sensor nodes which are capable of sensing different environmental phenomena and sending the collected data to the base station or sink. since sensor nodes are made of cheap components and are deployed in remote and uncontrolled environments, they are prone to failure; thus, maintaining a network with its proper functions even when und...

this paper presents an optimal integrated instrumentation sensor network design methodology for complex nonlinear chemical process plants using a combinatorial particle swarm optimiazation (cpso) engine. no comprehensive sensor network design approach has been addressed yet in the literature to simultaneously incorporate cost, precision and reliability requirements for nonlinear plants. the pre...

in this paper, design and construction of a tactile sensor for measuring contact-force is presented. mechanism of measuring contact-force in this tactile sensor is based on impedance changing of piezoelectric crystal and voltage of different points in circuit as a result of applying force on the crystal. by considering a specific point in the circuit and recording the changes of its voltage, ma...

The electrochemical sensor for detecting hydrogen sulfide was fabricated. H2S gas molecules pass through polytetrafluoroethylene membrane with 0.22 mm pore size. Carboxylated multi-walled carbon nanotubes (MWCNTs-COOH) were used to fabricate working and counter electrodes. It can be seen from Field Emission Scanning Electron Microscopy (FESEM) images of the working electrode that...

we report the development of different types of oxygen sensors based on yittria-stabilized zirconia (ysz) as a solid electrolyte. the conventional oxygen sensor is a concentration cell with two porous pt electrodes, one of which is exposed to air as a constant (reference) oxygen concentration and the other is exposed to automobile exhaust gas of variable oxygen concentration, depending on the a...