determination of 1, 1-dimethylhydrazine (dmh) in air is carried out by spectrophotometry, gc or hplc analysis, but in this study dmh was analyzed by a gas sensor based on nanostructure conducting polyaniline. determination of dmh has been done very simplely and quickly in recent work. electrically conductive fibers have been prepared by polymerization of aniline on surfaces of commercial polyme...

In this paper modeling of capacitance and sensitivity for MEMS capacitive pressure sensor is presented. In capacitive sensor the sensitivity is proportional to deflection and capacitance changes versus pressure. Therefore first the diaphragm displacement, capacitance and sensitivity of sensor with square diaphragm have been modeled and then simulated using finite element method (FEM).  It can b...

Today due to the importance and necessity of implementing security systems in homes and other buildings, systems with higher certainty, lower cost and with sensor fusion methods are more attractive, as an applicable and high performance methods for the researchers. In this paper, the application of Dempster-Shafer evidential theory and also the newer, more general one Dezert-Smarandache theory ...

Abstract   In this paper analytical analysis of capacitive pressure sensor with clamped diaphragm is presented. Mechanical and electrical properties of the sensor are theoretically analyzed based on theory of thin plates with small deflection and the results are evaluated by use of finite element analysis. The central deflection and capacitance values under uniform external pressure are calcula...

Fe2+ ion-selective membrane sensor has been fabricated from polyvinyl chloride (PVC) matrixmembrane containing neutral carrier tetra phenyl porphyrin (TPP) ionophore. The addition ofsodium tetraphenylborate (NaTPB) and the plasticizer DBP has been found to substantiallyimprove the performance of the sensor. The best performance was obtained with the sensor havinga membrane of composition of TPP...

This paper presents the design, construction and testing of a new capacitive tactile sensor for measurement of normal tactile force. The operation of proposed sensor has been investigated in ASTABLE and MONOSTABLE circuits. According to the results of these circuits the deviation of ASTABLE circuit results is less than MONOSTABLE circuit results. In addition, the results obtained from ASTABLE c...

In this paper we present a new model for calculating the capacitance of MEMS sensor with corrugated diaphragm. In this work the effect of residual stress is considered on deflection of diaphragm and capacitance of sensor. First, a new analytical analyzes have been carried out to derive mathematic expressions for central deflection of corrugated diaphragm and its relationship with residual stres...

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...

wireless sensor networks attracting a great deal of research interest. accurate localization of sensor nodes is a strong requirement in a wide area of applications. in recent years, several techniques have been proposed for localization in wireless sensor networks. in this paper we present a localization scheme with using only one mobile anchor station and received signal strength indicator tec...

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...