Influence of Optimization Techniques on Wire Electrical Discharge Machining of Ti–6Al–2Sn–4Zr–2Mo Alloy using Modeling Approach

Nowadays, the Wire Electrical Discharge Machining (WEDM) process was also working to cut the hard titanium alloys. During the WEDM, the generation of high temperatures was used to melt and vaporize and also flushed away the hard titanium alloy. The tough Ti–6Al–2Sn–4Zr–2Mo alloy was machined in the current research by the WEDM method and machining features such as surface roughness (SR) and Material Removal Rate (MRR) were statistically evaluated to achieve optimum performance. The investigations were performed using the Taguchi orthogonal array technique. The optimum process factors were defined from the main effect plot 32 μs, 3 m/min, and 12 g for material removal rate and as 10 μs, 32 μs, 7 m/min, and 12 g for surface roughness. The best essential parameters were established from the Analysis of variance (ANOVA) analysis. The pulse on-time current and pulse off time were identified as important parameters for the material removal rate with a contribution of 23.60%, 5.91%, and 65.02%. The best essential parameters for surface roughness were pulse on time, pulse off time, and a combination of pulse on-time and pulse off time with a percentage contribution of 22.71% and 36.88% respectively.Moreover, the machined surface was examined using the Scanning Electron Microscope (SEM).

     

On generalized similarity measures for Pythagorean fuzzy sets and their applications to multiple attribute decision-making

In this paper, we develop a new and flexible method for Pythagorean fuzzy decision-making using some trigonometric similarity measures. We first introduce two new generalized similarity measures between Pythagorean fuzzy sets based on cosine and cotangent functions and prove their validity. These similarity measures include some well-known Pythagorean fuzzy similarity measures as their particular and limiting cases. The measures are demonstrated to satisfy some very elegant properties which prepare the ground for applications in different areas. Further, the work defines a generalized hybrid trigonometric Pythagorean fuzzy similarity measure and discuss its properties with particular cases. Then, based on the generalized hybrid trigonometric Pythagorean fuzzy similarity measure, a method for dealing with multiple attribute decision-making problems under Pythagorean fuzzy environment is developed. Finally, a numerical example is given to demonstrate the flexibility and effectiveness of the developed approach in solving real-life problems.     

Exploration on sulfur/acid treatment of sepiolite composite positive electrode material for lithium-sulfur battery

High energy density battery system is endowed with more complex Lithium sulfur cathode whose electrochemical redox reaction and phase transition occurred due to multi electron participation. The different mole ratios of sepiolite mixed with sulfur were synthesized by acid cum thermal treatment method. The morphological analysis illustrates that the sepiolite powder is composed of micro fibrous bundles in the range of 1 μm to 10 μm. The sorption isotherms indicate that the sieved sepiolite (Sp) and different mole ratio (4, 6 and 8) of sepiolite/sulfur shows a type-IV isotherm of mesoporous material. The S/SvSp (sulfur/sieved sepiolite) composite cathode exhibits an initial discharge capacity of 1066 mAh g^?1 and attains a stable capacity of 596 mAh g^?1 during 40 cycles with 97% of efficiency. All the results correlated with the better electrochemical behaviour of electrode and it satisfies the needs of high energy density storage application.     

Infinite arrays and controlled deterministic table 0L array systems

Deterministic table 0L array systems with control are considered for the generation of infinite arrays. Rewriting of a rectangular array is done in parallel by a table of rules, the rightmost edge horizontally or the lowermost edge vertically downwards. The application of the tables is controlled by a control set. Cube-free and square-free infinite arrays are obtained as an application of this model. The adherence of the array language of a controlled deterministic table 0L array system is related to the adherence of its control set. The limit language equivalence problem and the adherence equivalence problem are shown to be undecidable for this system.     

Glycerol,glucose and 2-acetoacetoxyethyl methacrylate: Effect on methyl linolenate oxidation and yellowing

The effect of glycerol, glucose and acetoacetoxyethyl methacrylate (AAEM) on autoxidation and yellowing of methyl linolenate has been investigated by nuclear magnetic resonance (NMR) and ultraviolet (UV)-Visible spectroscopies. The extent of autoxidation was determined by measuring the NMR integration of vinylic protons with respect to methoxy protons, an internal standard, as a function of time. The extent of yellowing was determined by measuring the difference in absorbance at 400 nm and 450 nm as a function of time. Glycerol and AAEM showed inhibition of autoxidation, but the most significant effect was observed with AAEM. Glucose enhanced the autoxidation of methyl linolenate. Inhibition of yellowing was observed with all these compounds, especially with glycerol and AAEM.     

DESIGNING AND MANAGING CLIENT/SERVER DBMSs

Client/server systems have evolved from simple graphical front ends for relational data bases to object-oriented and distributed data bases. This article discusses the merits of the emerging technologies of the new generation of client/server systems—three-tier architectures, object-oriented data bases, object request broker systems, and replication—and the design and management issues in applications for such systems.     

A computational economy for grid computing and its implementation in the Nimrod-G resource broker

Computational grids that couple geographically distributed resources such as PCs, workstations, clusters, and scientific instruments, have emerged as a next generation computing platform for solving large-scale problems in science, engineering, and commerce. However, application development, resource management, and scheduling in these environments continue to be a complex undertaking. In this article, we discuss our efforts in developing a resource management system for scheduling computations on resources distributed across the world with varying quality of service (QoS). Our service-oriented grid computing system called Nimrod-G manages all operations associated with remote execution including resource discovery, trading, scheduling based on economic principles and a user-defined QoS requirement. The Nimrod-G resource broker is implemented by leveraging existing technologies such as Globus, and provides new services that are essential for constructing industrial-strength grids. We present the results of experiments using the Nimrod-G resource broker for scheduling parametric computations on the World Wide Grid (WWG) resources that span five continents.     

A comprehensive survey on image enhancement techniques with special emphasis on infrared images

Capturing of infrared images is an easy task but perceptual visualization is difficult due to environmental conditions such as light rain, partly cloudy, mostly cloudy, haze, poor lightening conditions, noise generated by the sensors, geographical distance and appearances of the objects. To improve the human perception and quality of the infrared images for further processing like image analysis, image enhancement is an essential process. This paper provides a detailed review of various image enhancement techniques from contrast stretching to optimization methods used in infrared images. It also discusses the existing infrared image enhancement techniques as group such as histogram based methods, filter based methods, transform domain based methods, morphological based methods, saliency extraction methods, fuzzy based methods, learning methods, optimization methods and its popular algorithms also address the countless issues. Some of the existing image enhancement methods (Histogram Equlization, Max-median filter, Top-Hat transform) and infrared image enhancement methods (multi-scale top-hat transform, adaptive infrared image enhancement) are implemented along with the adaptive fuzzy based infrared image enhancement method and its obtained results evaluation is done on subjective and objective ways. From the results observed that the fuzzy based method works well for both subjective and objective evaluation. The paper aims to provide a complete study on image enhancement techniques and how they specially utilized while dealing with infrared images. In addition, the paper helps the researchers to select the suitable infrared image enhancement techniques for their infrared image application needs.

     

Comparative Studies of Microwave and Sol–Gel-Assisted Combustion Methods of NiFe<Subscript>2</Subscript>O<Subscript>4</Subscript> Nanostructures: Synthesis,Structural, Morphological,Opto-magnetic,and Antimicrobial Activity

Nickel ferrite NiFe₂O₄ nanoparticles (NPs) were successfully synthesized by using nickel nitrate, ferric nitrate, citric acid, and ethyl cellulose as a surfactant by a simple sol–gel-assisted combustion method (SACM) and microwave-assisted combustion method (MACM). Structural, morphological, optical, and magnetic properties of the obtained powder were characterized by powder X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), photoluminescence (PL) spectroscopy, and vibrating sample magnetometry (VSM). XRD results show that the resultant powder was pure crystalline with cubic structure. The average crystalline size was found to be 18.8 and 10.2 nm synthesized by SACM and MACM, respectively. FT-IR spectra indicate the type of bonds between Ni–O and Fe–O (metal and oxygen). SEM images show that the morphology of the powder consists of well-defined structure. VSM results showed a ferromagnetic behavior of the sample. Antimicrobial activity of NiFe₂O₄ nanoparticles was performed. Both sample 1 (SACM) and sample 2 (MACM) show good inhibition in the zone 100 μg/ml. While comparing, sample 2 shows high inhibition than sample 1.