National Institute of Technology, Meghalaya

About: National Institute of Technology, Meghalaya is a education organization based out in Shillong, India. It is known for research contribution in the topics: Control theory & Computer science. The organization has 503 authors who have published 1062 publications receiving 6818 citations. The organization is also known as: NIT Meghalaya & NITM.

Formation of D–V Zn complex defects and possible p-type conductivity of ZnO nanoparticle via hydrogen adsorption

Abstract: The hydrogen adsorption on surfaces and on defect sites of ZnO nanoparticles (NPs) has been studied by using Raman and Fourier transform infrared spectroscopic methods. The presence of hydrogen at defect sites bound to zinc vacancy with different coordinations has been confirmed. To further identify the existence of isolated VZn and H–VZn complexes in the ZnO NPs, coincidence Doppler broadening (CDB) spectroscopic studies have been performed with respect to the CDB spectra of a 99.9999% pure Al single crystal. The broad momentum dip ρL showed between 15–17 × 10−3 m0c suggests the trapping of positrons with the core electrons of 3p Zn. However, positron annihilation takes place between ρL 20–25 × 10−3 m0c and this may occur with an electron belonging to OH bonds (VZn–Hi–O). Here the lattice hydrogen H+ ion acts as a compensating centre, and it can bind with the VZn around the dislocation and stacking faults (SFs) core, which may produce the acceptor-type complex defect for p-type conductivity. Finally, the existence of SFs and dislocation defects, including edges and steps, was confirmed by transmission electron microscopy.

Effect of Cyclic Loading Frequency on the Behavior of External RC Beam-Column Connections

Abstract: Reduced-scale external RC beam-column specimens with three typical deficiencies as beam weak in flexure (BWF), beam weak in shear (BWS) and column weak in shear (CWS) were tested under cyclic excitations of different frequencies, varying from 0.025–2.0 Hz. Parameters like load carrying capacity, stiffness degradation, energy dissipation, principal tensile stress were monitored for exploring the effect of rate of loading on different types of deficient beam-column connections in a holistic manner. Test results showed that the rate effect is significant in beam-column connection with BWF, while the same is not so significant in BWS and CWS specimens.

Automatic generation control of multi-area system using two Degree of Freedom Fractional Order PID Controller: A preliminary study

Abstract: In this paper, Two-Degree-of-Freedom-Fractional Order-PID (2-DOF-FOPID) Controller is presented for automatic generation control of an interconnected three unequal area thermal system. Performances of different fractional order (FO) based classical controllers such as FOI, FOPI and FOPID are studied and compared with proposed 2-DOF-FOPID controller. Recently developed metaheuristic nature-inspired algorithm known as Firefly algorithm (FA) are used for the simultaneous optimization of several parameters of the controllers and speed regulation parameter (R) of the governor. Simulation results clearly reveal the superiority of the proposed 2-DOF-FOPID controller. Further, the performances of proposed controller are tested against higher degree of perturbation. It is observed that 2-DOF-FOPID controller perform far better than aforesaid FO controllers.