(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

In this contribution, we derive expressions for carrier concentration and conductance in a Terahertz Photomixing Antenna (PMA) using a basic 2-ray model. We introduce a modulating signal into the analysis and assuming a basic ON/OFF keyed scheme for the modulating signal, we derive expressions for the carrier concentration and conductance. We investigate the effects of input power, angle of incidences of the two laser beams and the beat frequency on the carrier concentration in the PMA. © 2017 IEEE.

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Electrical Engineering

Applied Electromagnetics Conference, AEMC 2017

Analytical modelling of carrier concentration and conductance in Terahertz Photomixing Antennas

Scheduling a meeting is a difficult task for people who have overbooked calendars and often have many constraints. This activity becomes further complex when the meeting is to be scheduled between parties who are situated in geographically distant locations of a city and have varying traveling patterns. To achieve this, we first propose a solution to determine optimal meeting location for two moving users in the Euclidean space. Then, we generalize the problem by considering variable number of moving users and evaluate optimal meeting point on the road network. We extend the work of Yan et al. (Proc VLDB Endow 4(11):1–11, 2011) in this domain by incorporating some real life constraints like variable number of users, varying travel patterns, flexible meeting point and considering road network distance. Experiments are performed on a real-world dataset and show that our method is effective in stated conditions. © 2018, Springer-Verlag GmbH Austria, part of Springer Nature.

Computer Science and Engineering

Fulltext

Social Network Analysis and Mining

Mining optimal meeting points for moving users in spatio-temporal space

In this paper, we consider a tabletop molecular communication (MC) system for exchange of information through flow assisted diffusion of ethanol chemical molecules. Designing modulation and demodulation algorithms for such setup is an important research problem. We propose a demodulation algorithm using Sampling based Adaptive Threshold Variation (S-ATV) for Pulse Position Modulation (PPM) and ON/OFF keying (OOK) based modulation techniques. The performance of BER with bit duration is plotted for proposed demodulation algorithm as well as Increase detection algorithm (IDA). It is found that the proposed S-ATV demodulation algorithm has better performance than IDA for smaller bit durations. © 2018 IEEE.

International Symposium on Advanced Networks and Telecommunication Systems, ANTS

Experimental Implementation of Molecular Communication System using Sampling based Adaptive Threshold Variation Demodulation Algorithm

This paper presents a metamaterial approach based ultra-wideband patch antenna using a different split-ring resonator structure. The proposed split-ring resonator is constructed on a 0.43mm thick RT Duroid substrate above a partly covered ground plane. The radiating element comprises of a rectangular geometry with arc-shaped structures at the shorter edges, with an overall dimension of 39x30 mm2. The proposed antenna provides a much favorable radiation pattern with a very efficient impedance matching across a wide bandwidth of 3-44 GHz, making it highly suitable for its operation at and beyond ultra-wideband applications and 5G communications. This paper discusses the antenna's design and the parametrical studies performed using available simulation tools. © 2018 IEEE.

Proceedings - 2nd International Conference on Micro-Electronics and Telecommunication Engineering, ICMETE 2018

Metamaterial based compact planar antenna for UWB and 5G applications

<p>The authors report the development of AlxCoCrFeNi (x = 0.1 to 3) high entropy alloy (HEA) coatings using a simple and straightforward microwave technique. The microstructure of the developed coatings is composed of a cellular structure and diffused interface with the substrate. The microstructure of the HEA coatings varies as a direct function of Al content. An increase in Al fraction shows structural transformation from FCC to BCC along with the evolution of σ and B2 as the major secondary phases. The diffusion of Mo from the substrate enhances the mixing entropy and promotes σ-phase formation. The HEA coatings show significantly high hardness compared to SS316L substrate steel (227 HV) with a maximum value of 726 HV observed for three-molar composition. The fracture toughness exhibits an inverse correlation with the Al fraction with the highest value of around 49 MPa m1/2 observed for Al0.1CoCrFeNi coating. The equimolar coating composition shows lowest erosion rates among all the tested samples due to optimum combination of the mechanical properties. The erosion resistance of the equimolar coating is 2 to 5 times higher than steel substrate and around 1.5 times higher than the non-equimolar counterparts depending upon the impingement angles. © 2018 WILEY-VCH Verlag GmbH &amp; Co. KGaA, Weinheim</p>

Mechanical Engineering

Advanced Engineering Materials

High-Performance Microwave-Derived Multi-Principal Element Alloy Coatings for Tribological Application

Cavitation erosion remains the primary cause of material degradation in fluid machinery components operating at high speed. Micro-jets/shock waves caused by implosion of bubbles on material surface results in significant material loss and premature failure of the components. The presence of corrosive medium further exuberates this effect, causing rapid degradation. Here, we demonstrate a novel pathway to control cavitation erosion-corrosion by tailoring the surface properties using submerged friction stir processing (FSP), a severe plastic deformation process. FSP parameters were varied over wide range of strain-rates to generate tailored microstructures. High strain-rate processing resulted in nearly single phase fine grained structure while low strain-rate processing resulted in phase transformation in addition to grain refinement. As-received and processed samples were subjected to ultrasonic cavitation in distilled water as well as in corrosive environment of 3.5\% NaCl solution. Individual roles of cavitation erosion, corrosion and their synergistic effects were analyzed. Depending on the microstructure, processed samples showed nearly 4–6 times higher cavitation erosion resistance compared to as-received alloy. Superior cavitation erosion-corrosion resistance of processed samples was attributed to surface strengthening, higher strain-hardening ability and quick passivation kinetics. The results of current study could be potentially transformative in designing robust materials for hydro-dynamic applications. © 2018 Elsevier B.V.

Ultrasonics Sonochemistry

Ultrasonic cavitation erosion-corrosion behavior of friction stir processed stainless steel

The paper presents a multilevel inverter that can be employed for solar PV applications either for stand alone system or for the grid tied PV system. The multilevel inverter topology employed here is the cascaded multilevel inverter (CMI). In this paper single phase eleven level cascaded multilevel inverter is proposeded for grid integration of solar PV. They have the advantages of providing quality power output with high voltage compatibility. The inverter is simulated in MATLAB/Simulink environment with the phase shifted SPWM control, implemented for the inverter. Besides this the paper proposed a methodology to control the AC inverter module structure of SPV configuration so as to obtain a good harmonic quality output power from SPV panels with improved THD of this supply. The methodology permits a high voltage output with a low total harmonic distortion without using any particular means for the same. It is capable of synthesizing a staircase output voltage reaching nearer to the sine wave output. © 2017 IEEE.

2017 Recent Developments in Control, Automation and Power Engineering, RDCAPE 2017

A methodology for 11-level AC output voltage generation for stand-alone/grid tied solar PV applications

Assessment of the Translation done by machines has always been a major topic of interest for the Natural Language Researchers. Every day, a new translator is out there in the market claiming to be the best one. But to challenge such claims, one needs to have a powerful assessment tool that can judge the output of any translator on different parameters like fluency of the language, adequacy as well as the accuracy of the output generated. In this paper, we have discussed the major issues with the algorithms used for the evaluation of Machine translation. We have also presented a brief description and comparative study of different metrics used to evaluate the outcome of a machine translator over English to Hindi Language parallel sentences. © 2018 IEEE.

Proceedings of the 8th International Conference Confluence 2018 on Cloud Computing, Data Science and Engineering, Confluence 2018

A Summary and Comparative Study of Different Metrics for Machine Translation Evaluation

Wireless power transfer (WPT) is an emerging technology that could lead to the breakthrough of plug-in Electric Vehicles (EVs). It enables transfer of electric power from one coil to the other based on the principle of electromagnetic induction. Inductive coupling (IC) and magnetic resonance coupling (MRC) are the two main methods of WPT. In this paper, MRC technique is used to effectively transfer power over large air gaps. Low power transfer efficiency (PTE) is the major challenge in WPT charged EVs. This may causes due to misalignment between the transmitter (Tx) and the receiver (Rx) coils. Lateral and angular are two commonly occurring misalignments in the practical scenario of WPTS. This paper presents the simulation analysis of various factors, which effects PTE. In the analysis, the lateral misalignments are performed for distinct airgaps between Tx and Rx. Various modes of angular misalignments are presented for a fixed value of airgap between coils. In addition, the paper provides the effect of various cores and aluminum shielding on PTE for distinct air gaps are documented. © 2017 IEEE.

2017 14th IEEE India Council International Conference, INDICON 2017

Effect of Lateral and Angular Misalignments on Power Transfer Efficiency of a Wireless EV Charging System

We present an algorithm for maintaining a maximal matching in a graph under addition and deletion of edges. Our algorithm is randomized and it takes expected amortized O(log n) time for each edge update, where n is the number of vertices in the graph. Moreover, for any sequence of t edge updates, the total time taken by the algorithm is O(t log n + n log2 n) with high probability. © 2018 Society for Industrial and Applied Mathematics.