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.

Microscopic chaos control of chemical reactor system using nonlinear active plus proportional integral sliding mode control technique

Abstract: This paper puts forward the microscopic chaos control in the deterministic dynamics of the chemical reactor system. First, the dynamic behavior of the chemical reactor system is explored for some of the parameters and chaotic behavior is investigated. Phase plane, bifurcation plots and Lyapunov exponents are presented to verify the chaotic behavior. Second, nonlinear active plus proportional integral sliding mode control (NA-PISMC) is proposed to control microscopic chaos in the chemical reactor system. A proportional integral switching surface is proposed to achieve the stability condition of the error dynamics and controller is designed by using the relevant variables of the chemical system. Unlike the open loop and open plus closed loop control techniques, the design of proposed controller does not require the parameter perturbation. The required stability condition is derived based on Lyapunov stability theory. Simulation is done in MATLAB environment. Numerical simulation results are presented in order to show the effective performances of the proposed controller design. Simulation results correspond that the objectives of chaos existence and chaos control are achieved successfully.

Design of Compact and High Directive Slot Antennas Using Grounded Metamaterial Slab

Abstract: In this letter, a simple and compact approach for directivity enhancement of slot antenna using a grounded metamaterial slab is proposed. This approach has been applied in two different configurations. In the first configuration, two dielectric layers are used for designing antenna and metamaterial slab. Despite the directivity enhancement, an improved bandwidth of about 10.74% is obtained for this configuration. It is also shown that, over the whole working band, a significant broadside directivity improvement is maintained compared to the unloaded slot. In the second configuration, only a single layer of dielectric is used for designing both antenna and metamaterial slab. Thus, in this case, the total thickness of the loaded antenna is noticeably reduced to 0.5 mm, or $0.014 {\lambda _0}$ at resonance.

Characterization of non-covalent binding of 6-hydroxyflavone and 5,7-dihydroxyflavone with bovine hemoglobin: Multi-spectroscopic and molecular docking analyses.

Abstract: Flavonoids are biologically imperative compounds used as anti-oxidants, anti-cancer, anti-bacterial agents etc. The current work reports comprehensive binding studies of two important flavonoids, 6-hydroxyflavone and 5,7-dihydroxyflavone (chrysin) with bovine hemoglobin (BHb) at 298K and 308K, in aqueous medium using UV-vis spectroscopy, steady state fluorescence, circular dichroism (CD) measurements, Fourier Transform infrared spectroscopy (FT-IR) and molecular docking studies. Both 6-hydroxyflavone and chrysin can quench the intrinsic fluorescence intensity of BHb via static quenching mechanism. The values of binding constant (Kb) for BHb-chrysin complex (3.177±0.992×104M-1, at 298K) was found to be greater than that of BHb-6-hydroxyflavone complex (2.874±0.863×104M-1, at 298K) and the Kb values decreased with the rise in temperature. The thermodynamic parameters indicated that hydrophobic forces and H-bonding play crucial role in BHb-6-hydroxyflavone complexation whereas electrostatic interaction plays the major role in the binding of BHb and chrysin. The binding distances from donor BHb to the acceptor ligands (6-hydroxyflavone and chrysin) were estimated using the Foster's theory and the possibility of non-radiative energy transfer from BHb to 6-hydroxyflavone/chrysin was observed. The ligands, 6-hydroxyflavone and chrysin induced conformational change around Trp residues in BHb as confirmed by synchronous and 3D fluorescence results. CD and FT-IR studies indicated that the % α-helicity of BHb was enhanced due to 6-hydroxyflavone/chrysin binding. Both the flavonoids showed remarkable inhibitory effect towards BHb glycation. Hydrophobic probe (8-anilino-1-naphthalenesulfonic acid, ANS) displacement and molecular docking studies revealed that the ligands bind within the hydrophobic pocket of BHb.

A Novel Hybrid Neural Network-Based Multirobot Path Planning With Motion Coordination

Abstract: Multi-robot navigation is a challenging task, especially for many robots, since individual gains may more often than not adversely affect the global gain. This paper investigates the problem of multiple robots moving towards individual goals within a common workspace whereas the motion of every individual robot is deduced by a novel Particle Swarm Optimization (PSO) tuned Feed Forward Neural Network (FFNN). Motion coordination among the robots is implemented using a cooperative coordination algorithm that identifies critical robots and maintains cooperation count while actuating deviation in select robots. The contribution of this paper is twofold; firstly in hybridizing the Artificial Neural Network(ANN) by employing PSO, an evolutionary algorithm, to find optimal values of deviation for every critical robot using velocity and acceleration constraints, secondly ensuing the convergence of the PSO by carrying first and second order stability analysis. Experiments have been carried out to evaluate and validate the efficacy of the proposed coordination schemes by changing the number of robots under hundred different scenarios each, and the founded results demonstrate the efficacy of the proposed schemes.