(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

Exposure to wastewater treatment system (WWTS)-associated bioaerosols is not only linked with macro/field scale systems but also facilities which are operated in micro- and/or indoor environment such as university campus and research institutions. In this context, investigations on a laboratory-scale WWTS, adopting a sequential batch biofilm process and fed with synthetic municipal wastewater, were done in terms of its global treatment performance and characterization of emitted bioaerosols species. The microbial diversity of captured bioaerosols, collected through conventional particulate matter samplers, was identified on the basis of their metabolic properties using analytical profile index, biochemical tests, and other media specific growth patterns. Monitoring and analysis results of air quality in control and experimental period revealed that particulate emission from bioreactor increased the concentration of PM10 and PM2.5 up to 26.49 ± 4.18 µg/m3 and 12.84 ± 2.48 µg/m3 from an initial level of 17.26 ± 4.58 µg/m3 and 8.70 ± 1.84 µg/m3, respectively. Microscopic observations and staining characteristics revealed that cocci shape gram-negative and bacilli shape gram-positive bacteria dominated the bioaerosols with quantitative contribution as 70% and 9%, respectively. Based on the morphological and biochemical characterization, dominant isolated genera of opportunistic pathogenic bacteria in bioaerosols were identified as Escherichia coli, Bacillus cereus, Bacillus subtilis and Pseudomonas sp. with % dominance as 38.46, 13.46, 9.61 and 25, respectively. Overall, the findings of this study reiterate the concern of biological air pollution in research laboratories and represent an inevitable aspect for the validation of bioaerosol exposure in laboratory-scale WWTS workplaces. © 2022, The Author(s), under exclusive licence to Springer Nature B.V.

World University root node

Aerobiologia

Assessment and characterization of bioaerosols from an indoor environment-operated wastewater management facility: unraveling pathogenicity in research laboratories

<p>This article reports an in-depth study of interdigitated photoconductive antenna (IPCA) structures for broadband, high electric field, efficient terahertz (THz) generation and detection. The photoconductive antenna (PCA) is the key component which can be used as both the emitter and detector in the THz-time domain spectroscopy for imaging application. The proposed IPCA can easily overcome the limitations of conventional dipole or bow-tie PCA, like, less bandwidth, low optical-to-THz conversion efficiency and less radiated THz power. In this work, the performance of IPCAs, which is made of silver interdigitated electrodes and thin layer of low-temperature-grown GaAs (LTG-GaAs) on top of semi-insulating GaAs (SI-GaAs) substrate, has been studied by varying the geometry of the interdigitated elements until it reaches to the plasmonic limit. Several time- and frequency-dependent parameters, such as carrier density, conductance, impedance, photocurrent, bandwidth, optical-to-THz efficiency, THz radiated power, have been investigated thoroughly depending on the input ultrafast laser parameters, temperature-dependent mobility of photo-carriers and the dimension of the IPCAs. The Scharfetter and Gummel’s drift-diffusion model has been used to calculate the photo-carrier density while focuses the laser pulses at the gap of IPCA structures. The optimum results have been found in terms of single-cycle THz pulses of 0.3 ps, bandwidth of ∼<math xmlns="http://www.w3.org/1998/Math/MathML"><mo>∼</mo></math>&nbsp;13.8 THz, optical-to-THz efficiency of 0.1265% and average radiated power of 3.9564 mW for the 20-nm interdigitated electrode (teeth) width, i.e. 44 elements IPCA. The results of different dimensions of IPCAs have been compared among them and with the published conventional PCAs. These IPCAs will be very useful for future generation THz-transceiver systems.</p>

Electrical Engineering

Arabian Journal for Science and Engineering

Parametric Investigation of Interdigitated Photoconductive Antenna for Efficient Terahertz Applications

Droplet grouping is important in technical applications and in nature where more than one droplet is seen. Despite its relevance for such problems, the fundamentals of the grouping processes are not yet fully understood. Initial conditions that expedite or impede the formation of droplet groups have been studied, but a thorough investigation of the temporal and spatial evolution of the forces at play has not been conducted. In this work, the grouping process in monodisperse droplet streams is examined in detail by direct numerical simulation (DNS), for the first time, using the multiphase code Free Surface 3D. The code framework is based on the volume-of-fluid method and uses the piecewise linear interface calculation method to reconstruct the interface. A method is established to quantify the development and evolving differences of pressure and shear drag forces on each droplet in the stream using the available DNS data. The results show a linear increase in the difference between the forces, where the drag force on the leading droplet is always larger than that on the trailing droplet. A comprehensive parametric study reveals that, on the one hand, large initial inter-droplet separation and small group distances increase grouping time due to reduced difference in the drag coefficients. On the other hand, higher initial Reynolds numbers and larger irregularities in the geometrical arrangement promote droplet grouping. The flow field shows stable wake structures at initial Reynolds numbers of 300 and the onset of vortex shedding at Reynolds numbers of 500, affecting the next pair of droplets, even for larger separation distances. © 2022 Author(s).

Mechanical Engineering

Physics of Fluids

Investigation of droplet grouping in monodisperse streams by direct numerical simulations

In this investigation, numerical analysis of square butt, butt with V-groove and T-weld joint configurations have been performed to estimate transient temperature distributions and residual stresses. A computational welding simulation based on a prescribed temperature approach was used that works on thermal load input derived from temperature analysis. In the thermal analysis, welding heat source or torch temperature was considered as the prescribed value of temperature, which helps in simulating real welding conditions. The inclusion of filler metal in the numerical analysis replicates the real welding phenomenon, which provides temperature distribution along the true distance of the joints. The maximum temperature was observed at the weld pool area and decreased in parabolic shape toward the base metal. Residual stresses were measured along the selected path (in the mid of plates) that comprises node-to-node variation of stresses in both longitudinal and transverse directions. von Mises and Tresca stress criterion was adopted to show accumulated stresses in the weld joints. It was observed that stresses accumulated in the different configurations of weld joints were below the yield strength 210 MPa of SUS304 steel. Peak values of stresses were observed at weld beads and in the nearby regions. © 2022, The Indian Institute of Metals - IIM.

Transactions of the Indian Institute of Metals

Numerical Analysis of Different SUS304 Steel Weld Joint Configurations Using new Prescribed Temperature Approach

In this work, a three-dimensional thermomechanical finite element model has been developed to simulate the additive manufacturing process of a Ti-6Al-4V hip implant fabricated using the laser powder bed fusion process. The developed numerical model is used to predict the thermal fields, residual stresses, and part deformation during the printing process. To reduce the mass and consequently the weight of the hip implant, topology optimization has been carried out. Furthermore, the additively manufactured Ti-6Al-4V hip implant subjected to realistic loading conditions is analyzed. In the numerical model, new elements are activated for each layer to simulate the recoating of metal powder, and the thermal gradient, residual stress, and deformation associated with the layer are computed. It is observed that the implant geometry significantly influences the quality of the printed part. Topology-optimized geometry shows a notable reduction in residual stress generation and distortions, along with a significant reduction in mass. © IMechE 2022.

Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering

Finite element analysis and topology optimization of Ti-6Al-4V hip implant fabricated by laser powder bed fusion process

The Billboard magazine is a world renowned music publication since 1984 and it releases a weekly ranking of the top 100 songs in various categories such as rock, pop, hip-hop, etc. Several studies have determined that it is possible to predict the approximate bucket of ranks that a song is likely to chart in using social and subjective indicators. The definitions of these indicators however can change over time, thus rendering the previous classifications erroneous. Here, we report successful results from our experiments in predicting the ranks and the number of weeks the songs are likely to stay on the charts, using objective and well-defined features, obtained from Spotify’s Web API. It extends existing research about classifying songs into rank buckets of Top-10 and Top-40 using these objective features, demonstrating that it is possible to predict exact ranks of the songs within a root-mean-squared-error of 28 ranks and the number of weeks of charting within a root-mean-squared-error of 7 weeks, demonstrating definitive trends between individual features and the ranks of the songs, demonstrating that objective metadata about the songs serve as good indicators about the trends in the Billboard charts, and can be used to predict a song’s performance on the charts within acceptable error rates. © 2022, The Author(s), under exclusive license to Springer Nature Switzerland AG.

Computer Science and Engineering

Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)

Performance Prediction of Songs on Online Music Platforms

A single-layer, four-element multiple-input-multiple-output (MIMO) antenna for 5 GHz (5150–5850 MHz) band WLAN application is proposed. Each unit element consists of three sections and this behaves as a travelling wave antenna, which enables frequency scanning feature. The combination of orthogonal feeds and placement of elements introduce dual-polarisation, and pattern diversity respectively. Thus, the proposed MIMO antenna offers a higher degree of freedom (pattern diversity, frequency scanning and dual polarisation), which makes it exceptional. The proposed MIMO antenna has a maximum impedance bandwidth of 17% (4.93–5.87 GHz) corresponding to port 4 and isolation of 17.5 dB, which is achieved without additional decoupling/isolation enhancement circuits. The envelope correlation coefficient of 0.25, capacity loss less than 0.4 bits/sec/Hz, and the mean effective gain (MEG) ratio of 0 dB in the desired frequency band quantifies the diversity performance for WLAN applications. The proposed MIMO has gain from 2 to 5.5 dB and occupies a compact volume of 1.3 λ × 1.3 λ × 0.02 λ mm3, which may be one of the most miniaturised electrical configurations. © 2022 Informa UK Limited, trading as Taylor & Francis Group.

International Journal of Electronics

Travelling Wave Antenna Based MIMO for 5GHz WLAN Band Application With Pattern Diversity

There have been various attempts to leverage the massive amount of data generated from social media websites. The real-time nature of social media platforms can help detect events, especially in a metropolitan city. In this paper, a system is proposed, that detects traffic-related events and road conditions in real-time from tweets by using classification algorithms and custom-trained named entity recognition model (NER) to classify and extract contextual information and visualise it on a map to get an overall picture of the traffic conditions in a city. The proposed system is versatile and can be applied to other use cases such as detecting calamities, social unrest, etc. © 2022, The Author(s), under exclusive license to Springer Nature Switzerland AG.

Real-Time Detection and Visualization of Traffic Conditions by Mining Twitter Data

Smart transportation for warehouses focuses on moving of the products more secure and efficient. The paper focuses on different parts such as maintaining the safety of the products and the container, keeping track of the products being loaded, tracking the location of the container, alerting in the case of an accident, and also using efficient communication system in the case of an emergency. The first part of the paper deals with the safety of the products which involves keeping track of the surrounding parameters such as temperature, humidity, and fire (in case a fire broke out) by utilizing temperature, humidity sensor, and the fire sensor and also the accident detection using accelerometer and gyroscope. This part also deals with the information of the products using RFID and using conditional statements to verify whether the product is allotted to a specific container. The second part focuses on the communication system with which all the required alerts can be transmitted in the form of SMS and emails with the help of third-party APIs. Using the data from the emails, a software platform is used to automate the task of storing that data in Google sheets. The second part also deals with location tracking of the container using Google maps, which helps the person in-charge to keep track of the locations the container has been to. The final part deals with the implementation of the dashboard. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

Lecture Notes in Electrical Engineering

Smart Transportation for Warehouses

Network science is a domain in which we focus on studying complex networks like social networks, chemical networks, computer networks, telecommunication networks, cognitive networks, semantic networks, and biological networks. In recent years, link prediction in complex networks has become an active research field because of its various real-world applications. In this paper, we present a novel algorithm for link prediction influenced by the concept of vertex entropy and ego networks. We used 12 real-world datasets to evaluate the performance of the novel algorithm. Results are compared with the 12 baseline algorithm based on 4 metrics AUC, Precision, Prediction-Power, and Precision@K. Experimental results show the effectiveness of the novel algorithm. © 2022, The Author(s), under exclusive license to Springer Nature Switzerland AG.