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Availability of potable water is of great concern owing to increasing population and contamination of water sources. Solar distillation is an important strategy used for obtaining potable water from contaminated water. The solar distillation technique uses solar energy for distillation of water in a container called solar still. It evaporates contaminated or brackish water and condensate is collected as a pure form of water. Nonetheless, the condensate yield from typical 1 m2 solar still is very less and even not sufficient to fulfil the needs of an individual. In the present work the solar still of 1 m2 is coupled with a parabolic solar trough collector to evaluate the improvement in the condensate yield. The parabolic solar trough collector concentrates solar energy on a helical copper tube. Inlet water temperature of coupled solar still increased up to 15 °C as compared to uncoupled solar still. The increase in temperature enhances the condensate yield of coupled solar still.

The usage of low-quality components in communicating devices may introduce nonlinearity in the audio signals. The degree of nonlinearity may vary over time due to the nonstationary nature of audio signals. In the presence of nonlinear audio signals, the performance of an acoustic echo cancellation (AEC) scheme is impacted by two major limitations. The first one is related to the modeling accuracy, and the second one is related to the adaptation performance. The issue of modeling accuracy exists because the available nonlinear AEC (NAEC) schemes consider the nonlinearity as time-invariant and employ a fixed architecture to model the echo path. The adaptation performance issue occurs due to the conflicting requirements of fast convergence and low steady-state error. There is a need for an architecture that not only models the nonlinearity efficiently but also provides better performance in terms of convergence. In this paper, three new architectures convex combination functional link adaptive filter (CC-FLAF), improved CC-FLAF (ICC-FLAF), and variable step size CC-FLAF (VSSCC-FLAF) are proposed to overcome the above limitations. The proposed architectures are based on the combination of adaptive filters and variable step size approach. Computer simulations demonstrate the effectiveness of proposed architectures, in improving the nonlinear modeling performance for NAEC applications.

The usage of low-quality components in communicating devices introduces acoustic nonlinearity. The presence of nonlinearity creates challenges in noise cancellation applications, especially the acoustic echo cancellation (AEC) that requires an adaptive filter of a very high order. However, the functional link adaptive filter (FLAF) algorithm models the acoustic nonlinearity efficiently but shows slow convergence performance due to a very high filter order. To improve the convergence performance of the FLAF, the wavelet transform-domain FLAF (WTD-FLAF) is proposed for nonlinear AEC (NAEC) applications. The convergence rate is improved by decomposing a higher-order adaptive filter into smaller-order subfilters. The convergence speed improvement is gained at the expense of increased computational complexity. A low complexity version of the WTD-FLAF, named as selective update WTD-FLAF (SU-WTD-FLAF) algorithm, is also presented. The SU-WTD-FLAF algorithm is based on the selective coefficient update approach. Computer simulations demonstrate that the convergence performance of the proposed algorithms outperforms the standard FLAF.

Nanoparticles showed their efficacy in every aspect of engineering applications due to their exceptional properties. The objective of the present work is to critically present a brief overview of i...

A coupled thermal-mechanical finite element analysis of axisymmetric direct extrusion process using aluminum alloy has been carried out using commercial software package ABAQUS (Standard). Effect of process parameters such as coefficient of friction, die angle and die profile radius on maximum nodal temperature, maximum contact pressure, deformation homogeneity are investigated in this paper. Heat generation due to plastic deformation and frictional heat generated between interacting surfaces of die and billet are considered in the analysis. It is found that coefficient of friction has significant effect on maximum nodal temperature while little influence on deformation homogeneity. It is also gathered that die angle has a considerable effect on deformation and on contact extrusion pressure. Besides, this it is also found that die profile radius has an appreciable influence on contact extrusion pressure. This study helps in selection of appropriate process parameters for proper designing of direct extrusion process.

Torque is the force which gives the operator control over the movements of roots of teeth in bilateral direction. There are various pliers available to apply torque in individual tooth, but none of the pliers are capable of measuring accurately the degrees of torque incorporated, so we have attempted to make a modified torquing plier to incorporate and measure the degrees of incorporated torque precisely.

Nanomaterials consist of larger fraction of surface atoms and the fraction of surface atoms increases with the decrease in size. Increase in surface atoms and high surface area provides exceptional properties to nanomaterials. In internal combustion engine the nanoparticles are used as fuel or lubricant additives and in catalytic convertors. The nanoparticles added in fuel offer distinct advantages of improved combustion characteristics, shortened ignition delay and fast energy release. In lubricants addition of nanoparticles significantly reduces friction between contact surfaces. High reactivity of nanoparticles enhanced the performance of catalytic convertor.

In metal matrix composites non-uniform distribution of reinforcement particles resulted in adverse affect on the mechanical properties. It is of great interest to explore post-processing techniques that can eliminate particle distribution heterogeneity. Friction stir processing is a relatively newer technique used for post-processing of metal matrix composites to improve homogeneity in particles distribution. In friction stir processing, synergistic effect of stirring, extrusion and forging resulted in refinement of grains, reduction of reinforcement particles size, uniformity in particles distribution, reduction in microstructural heterogeneity and elimination of defects.

Abdominal pregnancy is a rare and life-threatening ectopic pregnancy, defined as an intraperitoneal implantation exclusive of tubal or ovarian implantation. Ectopic pregnancy represents about 1–2 % of all pregnancies with 95 % occurring in the fallopian tube. Abdominal pregnancies represent just 1 % of all ectopic pregnancies. The incidence of abdominal pregnancy is 1:10,000 live births, but advanced abdominal pregnancy is seen in 1:25,000 live births [1]. Its prognosis is poor, with a maternal mortality rate of 5–18 % and perinatal mortality rate of 40–90 %. Abdominal pregnancy with a live fetus at term is a rare condition. We present one such case.