(SoE) School of Engineering

<p>Shiv Nadar University is a comprehensive, multidisciplinary, research-focused, and student-centric University offering a full range of academic programs at the undergraduate, postgraduate and doctoral level. With state-of-the-art infrastructure, the University comprises of academic wings, sophisticated labs, international standard sports facilities, amphitheaters, auditorium, conference rooms and smart classrooms. The University&rsquo;s goal is to become internationally recognized for the quality of its research and creative endeavors and their applicability to improving quality of life, generating new insights and expanding the boundaries of human knowledge creativity. Committed to excellence in teaching, research and service, the University aims to serve the higher education needs of India and the world beyond.</p>

Shiv Nadar University

Erosion is a serious concern for machinery dealing with particle-laden fluids. For protection against erosion, coatings are usually recommended. Laboratory experiments are conducted to evaluate the erosion rates of these coatings. Alternatively, one could consider the use of modeling and simulation to predict the erosion rates. Although several models are available in literature for bulk materials, there is limited work reported in this direction for coatings. In present work, several models from literature were evaluated for their ability to predict the slurry erosion of coatings. A model based upon contact-fracture theory (CFT), proposed in present work, was also evaluated. Another variant of this model considered the effect of splat size. It was observed that none of the existing models evaluated in the present work could predict the erosion rates of the coatings. The proposed CFT model was able to predict the erosion rates with reasonable accuracy, whereas another variant of this model based upon splat size was observed to be inappropriate for predicting erosion rates of coatings. Possible reasons for the observed disparity are discussed. © 2014 Springer Science+Business Media.

Mechanical Engineering

World University root node

Tribology Letters

A phenomenological model for slurry erosion prediction of thermal spray coatings

This paper presents the experimental studies on self-breakdown-based single-gap plasma cathode electron (PCE) gun (5-20 kV/50-160 A) in argon, gas atmosphere and its performance evaluation based on particle-in-cell (PIC) simulation code OOPIC-Pro. The PCE-Gun works in conducting phase (low energy, high current) of pseudospark discharge. It produces an intense electron beam, which can propagate more than 200 mm in the drift space region without external magnetic field. The profile of this beam in the drift space region at different breakdown conditions (i.e., gas pressures and applied voltages) has been studied and the experimental results are compared with simulated values. It is demonstrated that30% beam current is lost during the propagation possibly due to space charge neutralization and collisions with neutral particles and walls. © Indian Academy of Sciences.

Electrical Engineering

Pramana - Journal of Physics

Performance evaluation of self-breakdown-based single-gap plasma cathode electron gun

In this paper we introduce an adaptive channel estimation scheme for two-way relay with node capability. The adaptive filter used is called Block Fast Array Multichannel 2D-Recursive Least Square (BFAM 2D-RLS). The modulation used is Orthogonal Frequency Division Multiplexing (OFDM) and channel estimation is done in the frequency domain. The proposed channel estimator considers correlation of channel frequency response in both time and frequency domain. The computational complexity is calculated and convergence performance of the adaptive channel estimator is studied. This paper also introduces an AOFDM scheme for two-way relay systems. The effect of channel estimation error on performance of Adaptive OFDM (AOFDM) is analyzed for pedestrian A (pedA) channel. All computer simulations are performed using MATLAB ®. © 2014 IEEE.

International Congress on Ultra Modern Telecommunications and Control Systems and Workshops

Performance study of BFAM 2D-RLS channel estimator for AOFDM based two-way relay

We address a version of the set-cover problem where we do not know the sets initially (and hence referred to as covert) but we can query an element to find out which sets contain this element as well as query a set to know the elements. We want to find a small set-cover using a minimal number of such queries. We present a Monte Carlo randomized algorithm that approximates an optimal set-cover of size OPT within 0(log N) factor with high probability using 0(log2 N) queries where N is the input size. We apply this technique to the network discovery problem that involves certifying all the edges and non-edges of an unknown n-vertices graph based on layered-graph queries from a minimal number of vertices. By reducing it to the covert set-cover problem we present an 0(log2 n)-competitive Monte Carlo randomized algorithm for the covert version of network discovery problem. The previously best known algorithm (Beerliova et al., 2006) has a competitive ratio of ρ2(√ n log n) and therefore our result achieves an exponential improvement.

Proceedings of the Indian National Science Academy

The covert set cover problem with applications to network discovery

In the present study, catalytic wet peroxidation (CWPO) process has been applied for the degradation of nitrobenzene bearing wastewater using copper impregnated granular activated carbon with hydrogen peroxide as oxidant. Various catalysts were prepared by varying the Cu loading on activated carbon and these were characterized by N2 adsorption-desorption, Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscope (FE-SEM), thermogravimetric analysis (TGA), temperature programmed reduction (TPR) and UV-visible diffuse reflectance spectra (UV-DRS). Effect of parameters such as copper loading, pH, catalyst dose, hydrogen peroxide dose and temperature were explored on nitrobenzene and total organic carbon (TOC) removal. TOC removal of 89% was achieved after 4 h treatment at optimum condition of Cu loading = 2.5 wt%, pH ≈ 3.0, catalyst dosage = 0.25 g/l, oxidant dosage = 4.5 (moles of oxidant/moles of NB) and temperature = 55 C. © 2014 Elsevier B.V. All rights reserved.

Chemical Engineering

Separation and Purification Technology

Catalytic oxidation of nitrobenzene by copper loaded activated carbon

Mobile agents in wireless sensor networks provide many advantages in comparison of conventional client/server architecture. Mobile Agents follow code to data approach and thus perform the task of data aggregation at the nodes rather than at the processing element. This approach reduces in-network data transmission, thus improving bandwidth usage and prolonging network lifetime. Use of multiple mobile agents instead of single mobile agent allows the task to get completed in a cooperative manner. In this paper, we present a multi agent solution for data aggregation using source grouping along with tree based ordering. Extensive simulations have proved better results in terms of energy consumed and latency in comparison of other approaches. © 2014 IEEE.

Computer Science and Engineering

Proceedings of the 2014 International Conference on Advances in Computing, Communications and Informatics, ICACCI 2014

Multi-Agent data aggregation in wireless sensor network using source grouping

Structural changes in a bulk metallic glass subjected to high-strain plastic deformation was investigated. A zirconium-based bulk metallic glass was friction stir processed at different tool rotational speeds. The alloy retained its fully amorphous structure at lower speed. At higher tool rotational speed there was partial nano-crystallization with nearly three times increase in surface hardness. Changes in the glass transition temperature, relaxation and crystallization enthalpies were analyzed to explain the physics of high-strain deformation in amorphous metals. © 2014 Elsevier B.V.

Materials Science and Engineering A

Structural changes in amorphous metals from high-strain plastic deformation

Friction stir processing (FSP) of Mg based AE42 alloy was performed under single pass as well as double pass conditions. The evolution of microstructure was investigated using electron back scatter diffraction (EBSD) analysis. EBSD revealed that the grain size and texture varies within the nugget zone of friction stir processed region. The variation of mechanical properties across the nugget region was evaluated using nanoindentation. Hardness and Young's modulus was found to increase along the depth of the friction stir processed specimen. This was attributed to a finer grain structure with increasing depth. The friction stir processed specimen showed higher tendency toward strain hardening compared to as-cast alloy. Understanding microstructure-property relationship paves the way for optimization of FSP conditions and development of advanced functional Mg alloys. Friction stir processing (FSP) of Mg based AE42 alloy is investigated. EBSD analysis revealed that the grain size got more refined with increasing depth across the specimen cross-section. Hardness and Young's modulus is also found to increase along the depth of the friction stir processed specimen. The friction stir processed specimen show higher tendency towards strain hardening compared to as-cast alloy which is attributed to the fine in situ precipitates. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Advanced Engineering Materials

Microstructure-property relationship for friction stir processed magnesium alloy

There has been continuous development in the wildlife DNA forensics research that relied on the collection and analysis of the biological samples over the past many years. But there is not enough progress to develop computational algorithms which could make the process of finding the origin of species easier and faster. Computational algorithms based on phylogenetic networks are capable of providing evidence to assist in wildlife law enforcement and species conversation. Our new algorithmic rule first rudiment to spot sample set, provides a promising new model for the strong reasoning of substructure and ancestry of wildlife trade. Our findings establish a clear evolutionary connection among many different problem sets.

ACM International Conference Proceeding Series

Detecting history of species using mining of motifs in phylogenetic networks

Electrodeposited bismuth telluride (Bi2Te3) nanowires using anodic alumina (AAO) templates show anisotropic thermal properties in a direction parallel and perpendicular to the nanowire/nanochannel axis. The present study reports thermal diffusivity measurement of templated Bi 2Te3 nanowires in a direction perpendicular to the nanowire axis, using an active infrared thermography based noncontact technique. Measurements were performed on empty AAO templates of varying pore dimensions, AAO/Bi2Te3 nanocomposites and a single crystal Bi 2Te3 sample. A first order lower bound model estimation showed nearly five-fold reduction of thermal conductivity in 200 nm Bi 2Te3 nanowires as compared to the bulk values. © 2013 Elsevier B.V.