National Institute of Technology Calicut

About: National Institute of Technology Calicut is a education organization based out in Kozhikode, Kerala, India. It is known for research contribution in the topics: Computer science & Control theory. The organization has 3627 authors who have published 4638 publications receiving 50830 citations. The organization is also known as: Calicut Regional Engineering College & NIT Calicut.

Effect of ZrO2 Nanoparticle Deposited Layer on Pool Boiling Heat Transfer Enhancement

Abstract: Nanofluid preparation and its deposition on metallic surfaces are in wide practice due to their enhancement capability in the pool boiling heat transfer. The effect of zirconia nanoparticles coated...

New fixed point results in quasi-metric spaces and applications in fractals theory

Abstract: In this paper, we prove some fixed point theorems for ψF-contractions in the framework of quasi-metric spaces generalizing and improving several similar results in metric spaces. At the same time, we consider iterated function systems consisting of ψF-contractions on quasi-metric spaces, and we give some sufficient conditions for the existence and uniqueness of their attractor which is, generally, a fractal. Some illustrative examples are provided.

Importance and Requirement of Frequency Band Specific RF Probes EM Models in Sub-THz and THz Measurements up to 500 GHz

Abstract: In this letter, we present on-silicon structures on-wafer measurements up to 500 GHz and a comprehensive electromagnetic (EM) simulation analysis to understand nonideal behavior in the measured data The EM simulations are performed in such a way that the simulation setup remains very close to the physical measurement environment where a faithful EM model of the RF probes is an essential requirement In this process, four different commercial RF probes used during measurements in the frequency bands 1–110 GHz, 140–220 GHz, 220–325 GHz, and 325–500 GHz are closely designed in the EM simulator We also highlight the importance of the frequency band specific probe models to develop a deep understanding of the problems encountered in the sub-THz and THz measurements

Parametric identification of fractional-order nonlinear systems

Abstract: This work presents a new method for the identification of fractional-order nonlinear systems from time domain data. A parametric identification technique for integer-order systems using multiple trials is generalized and adapted for identification of fractional-order nonlinear systems. The time response of the system to be identified by two different harmonic excitations are considered. An initial value of the fractional-order term is assumed. Other system parameters are identified for each of the trial data by finding the pseudo-inverse of an equivalent algebraic system. A termination criterion is specified in terms of the error between identified values of system parameters from the two trials. If the error in system parameters does not fall in the specified tolerance, the value of the fractional-order term is varied using gradient descent method and identification is carried out until convergence. The validity of the proposed algorithm is demonstrated by applying it to fractional-order Duffing, van der Pol and van der Pol–Duffing oscillators. Numerical simulations show that the exact and identified parameters are in very close agreement. Comparison of the time taken for identification by the proposed method and those which define error in terms of time response shows the effectiveness of the method. Furthermore, the validity of the proposed method for identification of chaotic fractional-order systems is demonstrated by showing that the identified values are independent of signal time length used.