(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

Flying vehicle that is propelled by flapping wings also known as flapping-wing air vehicles (FWAV)/Ornithopters has been a subject of exploration due of its possible use towards unmanned air vehicles (UAV), micro air vehicles (MAVs). Birds and insects fly with unprecedented agility in flight. These FWAVs seek to mimic the motions of such naturally found species. They can find their use in military surveillance or for forestry and wildlife survey. Ornithopters are vehicles that generate the necessary thrust and lift by flapping motion. This exploration work contains a detailed description of the mechanical and the electrical systems used in the FWAV. This paper also focuses on the production process involved in the making of FWAV. This paper also gives an insight about the initial control experiments that were performed. Instead of focusing on problems of small MAV which revolves around miniaturization of the mechanism and electrical energy storage. Our work concerns itself more with the topic of robot locomotion. Thus, it will give details about how one can achieve better stability and control on the flight of an Ornithopter. The developed FWAV has a wingspan of 1.17 m, designed for a kerb weight of 1000 grams. The prototype has been designed specifically for the use of exploration. The designing make extra efforts to enhance payload size, control stabilization, wing efficiency and crash survivability. © Springer Nature Singapore Pte Ltd. 2019.

Mechanical Engineering

Lecture Notes in Mechanical Engineering

Designing a biomimetic flapping-wing air vehicle capable of controlled and sustained flight

This paper presents the concept of reinforcement learning-based field-oriented control (FOC) of induction motor. Conventional controllers such as PID used for FOC of induction machines are model-based controllers and face the issue of parameter tuning. Periodic retuning of PID controllers is required to take care of model approximations, parameter variations of the system during operation and external disturbances which are random in character, magnitudes, and place of occurrences in the system. Reinforcement learning is a model-free and online learning technique which can take care of parameter variations. These properties make reinforcement learning a potential candidate, to act as an adaptive controller which can replace conventional controllers. In this study, reinforcement learning-based controller has been designed to control the speed of induction machine using filed-oriented control. The controller performance has been verified for various operating conditions by computer simulation in MATLAB/SIMULINK. © Springer Nature Singapore Pte Ltd. 2019

Electrical Engineering

Advances in Intelligent Systems and Computing

Reinforcement learning-based controller for field-oriented control of induction machine

Multiple voids and cracks were generated during material processing techniques, which interact with each other and affects the service performance of piezoelectric components. This work aims to study the behavior of piezoelectric components in presence of multiple cracks under thermo-electro-mechanical loading environment. Extended finite element method has been implemented to model geometrical discontinuities with crack interaction phenomenon. In this work, thermo-electro- mechanical problem has been decoupled into thermal and electro-elastic problems. Temperature distribution has been obtained by solving heat conduction equation and then used as an input to the electro-elastic problem. In post processing phase, interaction integral method and generalized Stroh formalism were used to predict the stress intensity factors. The methodology has been implemented with in-house developed MATLAB code. Set of cases for crack interaction studies were presented using the proposed approach. © 2018, Springer Nature B.V.

World University root node

International Journal of Mechanics and Materials in Design

Crack interaction study in piezoelectric materials under thermo-electro-mechanical loading environment

In present work, we investigated the tribological behavior of the high entropy alloy (HEA) claddings under different degrading environments viz, slurry erosion-corrosion, liquid impingement erosion, electrochemical corrosion, and sliding wear. The HEA claddings were developed by varying Al fraction (AlxCoCrFeNi) (x = 0.1 to 3) using microwave processing. The claddings were composed of cellular structure with intermetallic phases segregated in the intercellular region. Variation in Al content showed significant influence on the microstructure and mechanical properties. The hardness of the claddings increased with an increase in Al fraction with a maximum value of 624 HV observed for the cladding containing three molar Al. Correspondingly, the fracture toughness showed an opposing trend. All claddings showed better wear resistance than SS316L with equimolar composition outperforming other counterparts. The equimolar HEA cladding showed 3 to 23 times higher wear resistance compared to SS316L steel depending upon test conditions. Inimitable wear resilience of the equimolar composition was attributed to its high hardness and strain-hardening ability. Surface morphologies of the tested claddings indicated the presence of ductile-brittle mixed damage modes. The tested surfaces showed numerous pits and cracks with delaminated secondary phase. Presence of groves and signs of delamination were also observed in case of sliding wear. The results of the present work show that microwave synthesized equimolar HEAs can effectively counter different tribological forms. © 2019 Elsevier B.V.

Wear

Tribological behavior of microwave synthesized high entropy alloy claddings

Cervical cancer affects 570,000 women globally and is among the most common causes of cancer-related deaths. Cervical cancer is caused due to the Human Papilloma Virus (HPV) which leads to abnormal growth of cells in the cervix region. Regular testing for HPV in women has helped reduce the death rate in developed countries. However, developing nations are still struggling to provide low-cost solutions due to the lack of affordable medical facilities. The skewed ratio of the oncologists to patients has also aggravated the problem. Motivated by the Deep Learning solutions in Bio-medical imaging, we propose a novel CervixNet methodology which performs image enhancement on cervigrams followed by Segmenting the Region of Interest (RoI) and then classifying the RoI to determine the appropriate treatment. For the classification task, a novel Hierarchical Convolutional Mixture of Experts (HCME) algorithm is proposed. HCME is capable of tackling the problem of overfitting, given that small datasets are an inherent problem in the field of biomedical imaging. Our proposed methodology has outperformed all the existing methodologies on publicly available Intel and Mobile-ODT Kaggle dataset giving an Accuracy of 96.77\% and kappa score of 0.951. Hence, the results obtained validate our approach to provide first level screening at a low cost. © 2019 IEEE.

Computer Science and Engineering

Proceedings - 2019 IEEE 19th International Conference on Bioinformatics and Bioengineering, BIBE 2019

Cervical Cancer Diagnosis using CervixNet - A Deep Learning Approach

Heterocoronene, a new redox-active core fragment, is utilized for the synthesis of room-temperature columnar discotic liquid crystals (DLCs). Three wedge-shaped side chains having different lengths of alkyl tails are introduced at the periphery of the heterocoronene core to prepare three kinds of discotic molecules, 1 (R = C10H21), 2 (R = C12H25), and 3 (R = C14H29). X-ray diffraction (XRD) analysis confirmed the packing variation in the columnar lattices regulated by alkyl chains of discrete length and steric bulk. When used in space charge limited current devices, compound 1 exhibits a high hole mobility value of 8.84 cm2/V s at ambient temperature, whereas compounds 2 and 3 show efficient ambipolar charge transport behavior with maximum hole (μh) and electron (μe) mobilities of 0.70 and 3.59 cm2/V s, respectively, for compound 3. The mobility values (μh = 8.84 cm2/V s for 1 and μe = 3.59 cm2/V s for 3) are remarkable and the highest ever disclosed for any DLC-based organic semiconductor, promising to deliver a good balance between mobility and processability in devices. The grazing incidence small- and wide-angle X-ray scattering experiments are employed to quantify the extent of alignment in the film state, which correlates with the observed trend of mobility values. © 2019 American Chemical Society.

Fulltext

Journal of the American Chemical Society

High Hole Mobility and Efficient Ambipolar Charge Transport in Heterocoronene-Based Ordered Columnar Discotics

The popularity of social networks make them most efficient to integrate into the Emergency Management process. Posts on social networking sites can help people by ensuring timely detection of an emergency. Often during the situations of a natural disaster, there is an information chasm created between the affected and the unaffected area that further compounds the confusion and chaos. In this paper, we examine the various challenges that exist while attempting to integrate social networks and Emergency Management and trace the state-of-art techniques that exist in various domains that come together for this Emergency Management system. We propose an end-to-end framework that takes public posts from social networking sites and converts it into a structured format that makes the information actionable. A summarization technique may be applied to the acquired information post mining of social media feed to convert everything into a text message that can be released into various social platforms. To increase the reach of this post and to warrant better public participation in the crisis in a timely manner, we apply influence maximization techniques and monitor the diffusion process of this generated post through a diffusion modelling technique that we propose. We conduct experiments to analyze the performance of this model and of the influence maximization process and conclude with an analysis of the experiments and the observed results and list out improvements that we intend to incorporate in future versions of this work. © 2019 IEEE.

IEEE Region 10 Annual International Conference, Proceedings/TENCON

Emergency Management using Social Networks

This paper presents a novel approach for the conversion of an implicit current-voltage (I-V) expression of a double diode model (DDM) photovoltaic (PV) module to an explicit expression of current in terms of voltage. A new method is proposed for the estimation of maximum power point (MPP) of a DDM PV module using the explicit I-V expression of a PV module under uniform irradiance condition. Further, a new mathematical model of a partially shaded PV array is developed using the proposed explicit expression. Since the explicit I-V expression is used for the estimation of MPP of a DDM PV module under uniform and nonuniform irradiance conditions, the estimation of MPP is simple, accurate, and efficient. The accuracy of the explicit expression is verified considering three different PV modules. A comparison of MPP of a DDM PV module extracted using the proposed method with different existing methods under different environmental conditions (DECs) is presented. The results obtained using the proposed method are validated with the experimental results under DEC. Also, the accuracy of the estimated global MPP of a PV array under partial shading conditions is verified. © 1982-2012 IEEE.

IEEE Transactions on Industrial Electronics

Estimation of MPP of a Double Diode Model PV Module from Explicit I-V Characteristic

Location Based Social Networks (LBSNs) like Twitter, Foursquare or Instagram are a very good source of extracting human generated data in the form of check-ins, location and social relationships among users. Location data bridges the gap between the physical and digital worlds and enables a deeper understanding of users preference and behaviour. There are many underlying patterns in this type of dataset of human mobility which are utilised for applications like recommender systems. The current approaches involve extracting data from user-item rating, GPS trajectories, or other forms of data, whereas we focus on an integrated model considering factors like user's interest, social influence, time and proximity. There is metadata associated with this dataset which tells us about the whereabouts of the user, with emphasis on types of places. This paper proposes an integrated location recommendation model that considers users' interests, their friends influences, time and seasonality factors, and users' willingness to visit distant locations. We integrate all these parameters to generate a ranked list of locations which will be recommended to the user. Experiments are performed on a real-world dataset which show that our proposed model is effective in the stated conditions. © 2019 IEEE.

Influence-Time-Proximity Driven Locations Recommendation Model: An Integrated Approach

Prominent requirements such as high data rate demands across weaker coverage areas have lead to the utilization of cooperative communication system in fifth generation (5G) networks. In this regard, this paper presents a novel joint transmit power sharing and relay placement scheme for decode-and-forward relay assisted secure communication to a legitimate user in the presence of an untrusted user. Observing that the joint secure rate maximization problem for the trusted user is non-convex, first we present key insights on optimal power sharing between source and relay, and then derive an equivalent single variable problem on relay placement. Next, tight analytical bounds for optimal relay placement are discoursed to ultimately come up with a computationally efficient joint global optimization algorithm. Lastly, the selected numerical results validate the analysis and highlight the substantial gains achieved by the proposed joint design over benchmark scheme. © 2019 IEEE.