Jadavpur University

About: Jadavpur University is a education organization based out in Kolkata, India. It is known for research contribution in the topics: Population & Fuzzy logic. The organization has 10856 authors who have published 27678 publications receiving 422069 citations. The organization is also known as: JU & Jadabpur University.

Fast response methane sensor using nanocrystalline zinc oxide thin films derived by sol–gel method

Abstract: Undoped nanocrystalline n-ZnO thin films were deposited on SiO 2 -coated p-Si substrates by sol–gel technique to fabricate ZnO-based resistive sensors for methane detection. The resistance change was studied at different temperatures (50, 150, 200, 250, 300 and 350 °C) with two different metallic contacts to ZnO, e.g. gold and palladium-silver, in air and in the presence of three different concentrations (0.1, 0.5 and 1%) of methane in N 2 carrier gas. The response, response time and recovery time were studied in detail. A significant improvement of the sensor performance was observed with a Pd-Ag (26%) contact. The maximum response of 74.3% and the lowest response time of 16.3 s were obtained at 250 °C using the Pd-Ag (26%) catalytic metal contact to ZnO. The mechanism of sensing by ZnO was suggested similar to that of the SnO 2 sensors reported by Yamazoe.

Design of fractional order PIλDμ controllers with an improved differential evolution

Abstract: Differential Evolution (DE) has recently emerged as a simple yet very powerful technique for real parameter optimization. This article describes an application of DE for the design of Fractional-Order Proportional-Integral-Derivative (FOPID) Controllers involving fractional order integrator and fractional order differentiator. FOPID controllers' parameters are composed of the proportionality constant, integral constant, derivative constant, derivative order and integral order, and its design is more complex than that of conventional integer order PID controller. Here the controller synthesis is based on user-specified peak overshoot and rise time and has been formulated as a single objective optimization problem. In order to digitally realize the fractional order closed loop transfer function of the designed plant, Tustin operator-based CFE (continued fraction expansion) scheme was used in this work. Simulation examples as well as comparisons of DE with two other state-of-the-art optimization techniques (Particle Swarm Optimization and Bacterial Foraging Optimization Algorithm) over the same problems demonstrate the superiority of the proposed approach especially for actuating fractional order plants.