A higher-order polynomial shear deformation theory for geometrically nonlinear free vibration response of laminated composite plate

In this paper, a nonlinear analysis for large amplitude free vibration of laminated composite plates is developed using higher-order shear deformation theory. The effect of all higher-order terms arising from nonlinear strain-displacement relations are included in the formulation and present plate theory exhibits traction-free surface of the laminated plate in von-Karman sense. A finite element procedure considering a C° continuous isoparametric nine-node rectangular element is implemented for nonlinear model. The accuracy of the theory is validated with some available theory for different aspect ratio, modular ratio, number of layers, ply orientations, etc. through some numerical examples.     

A Comprehensive Review of Path Planning Algorithms for Autonomous Underwater Vehicles

Machine Intelligence Research - The underwater path planning problem deals with finding an optimal or sub-optimal route between an origin point and a termination point in marine environments. The...     

Improved spotted hyena optimizer with space transformational search for training pi-sigma higher order neural network

Spotted hyena optimizer (SHO) is a recently developed swarm-based algorithm in the field of metaheuristic research, for solving realistic engineering design constraint and unconstrained difficulties. To resolve complicated nonlinear physical world tasks, at times, SHO reveals deprived performance concerning to explorative strength. So, to enhance the explorative strength along with exploitation in the search region, an attempt has been made by proposing the enhanced version of classical SHO. The suggested method is designated as space transformation search (STS)-SHO. In STS-SHO, a new evolutionary technique named as STS technique has been incorporated with original SHO. The suggested method has been assessed by IEEE CEC 2017 benchmark problems. The efficacy of the said method has been proven by using standard measures such as given performance metrics in CEC 2017, complexity analysis, convergence analysis, and statistical implications. Further as real-world application, the said algorithm has been applied to train pi-sigma neural network by means of 13 benchmark datasets considered from UCI depository. From the article it can be concluded that the suggested method STS-SHO is an effective and trustworthy algorithm, which has the ability to resolve real-life optimization complications.     

Study of chemically reactive and thermally radiative Casson nanofluid flow past a stretching sheet with a heat source

Nanoparticle (NP) delivery is an exciting and rapidly developing field that adequately takes care of thermal radiation in blood flow and is likely to have bearing on the therapeutic procedure of hyperthermia, blood flow, and heat transfer in capillaries. The NP parameters such as size, shape, and surface characteristics can be regulated to improve nano-drug delivery efficiency in biological systems. The NPs outperform traditional drug delivery processes in drug carrying capacity and controlled release. The current article investigates the boundary layer flow and heat transfer of thermally radiative Casson nanofluid (NF) over a stretching sheet with chemical reaction and internal heat source. In our study, Cu and Al₂O₃ are taken as NPs in a suitable base fluid. The problem is analyzed by using similarity transformations and is solved with MATLAB's built-in solver bvp4c. The effects of pertinent parameters characterizing the flow model are presented through graphs and tables. The important findings of the investigation are noted as: the use of metallic oxide is more beneficial to attain higher temperature within a few layers close to the bounding surface; the appearance of convexity and concavity in the concentration profile attributed to flow instability, and the constructive and destructive heterogeneous reactions at the bounding surface have distinct roles to modify the NF flow in the boundary layer.     

An improved adaptive differential evolution optimizer for non-convex Economic Dispatch Problems

The present paper proposes an improved adaptive differential evolution algorithm, the IL-SHADE algorithm, to solve Economic Dispatch Problems (EDPs) taking into account practical constraints, such as transmission network losses, ramp rate limit, prohibited operation zone and valve point effect. The IL-SHADE algorithm is introduced as an improved version of the L-SHADE algorithm (Success-History based Adaptive Differential Evolution algorithm with Linear population size reduction). The proposed algorithm is first tested on eight CEC’05 standard benchmark test functions. Then, the efficiency of the proposed optimizer is demonstrated by solving different practical EDPs related to three IEEE power test systems, the IEEE 6-unit, 40-unit and 140-unit test systems. The comparison with various recent state-of-the-art approaches proves that IL-SHADE outperforms the L-SHADE and other cited approaches. Finally, the Wilcoxon sign rank test is used to validate the results.     

A simplified state-of-the-art sample shifting technique for microcontroller based single phase power measurement

A unique state-of-the art sample shifting technique (SST), proposed in recent literature, is utilized particularly for the estimation of reactive power from sample values of voltage and current signals only while the active power is evaluated from their as usual product. Also all other related parameters, as described in the IEEE 1459-2010 standard, are estimated in this measurement. A hardware prototype is developed to study its viability by estimating the measurement errors under pure and different polluted environment conditions.     

Sensitivity of transverse shift inside a double-grating Talbot interferometer

We study the Talbot interferometry with an additional mask grating located behind the diffraction grating. The self-imaging so-called, Talbot carpet, can be very sensitive to an external perturbation. We here show the measurement and the optimization of sensitivity of transverse shift of one of the two gratings inside Talbot interferometer as a function of grating constant and opening fraction of the grating itself. The results show that the sensitivity of the transverse shift is increased dramatically at smaller grating constants while no effect for different opening fractions. A sensor of our simple scheme can be suggested as an excellent inertial sensing applications such as displacement sensor, spectrometer, and vibration sensor.     

Automatic generation control of multi area thermal system using Bat algorithm optimized PD–PID cascade controller

This article presents automatic generation control (AGC) of an interconnected multi area thermal system. The control areas are provided with single reheat turbine and generation rate constraints of 3%/min. A maiden attempt has been made to apply a Proportional derivative–Proportional integral derivative (PD–PID) cascade controller in AGC. Controller gains are optimized simultaneously using more recent and powerful evolutionary computational technique Bat algorithm (BA). Performance of classical controllers such as Proportional Integral (PI) and Proportional Integral Derivative (PID) controller are investigated and compared with PD–PID cascade controller. Investigations reveal that PI, and PID provide more or less same response where as PD–PID cascade controller provides much better response than the later. Dynamic analysis has also been carried out for the controllers in presence of random load pattern, which reveals the superior performance of the PD–PID cascade controller. Sensitivity analysis reveals that the BA optimized PD–PID Cascade controller parameters obtained at nominal condition of loading, size and position of disturbance and system parameter (Inertia constant, H) are robust and need not be reset with wide changes in system loading, size, position of disturbance and system parameters. The system dynamic performances are studied with 1% step load perturbation in Area1.