(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

Storaci-Mobile phone communication has become heart of the Global economic development over past decade. As the number of users (human as well as devices) grow exponentially with each year, there is an immense need to increase capacity and throughput with minimum possible upgradation in vast existing network. The 4G-LTE cellular network capacity can be increased by massive deployment of small cells and leveraging very high frequency bands in conjunction with a Macro cell. The presence and usage of small (Phantom) cells are dynamically controlled by a Macro cell. The connection between user equipment (UE) and small cell nodes is achieved by using control and user (C/U) planes splitted at radio link. It can achieve high capacity enhancement by massive deployment of small cells. NS-3 simulations were carried out and results shows capacity enhancement and throughput. © 2017 IEEE.

Electrical Engineering

IMPACT 2017 - International Conference on Multimedia, Signal Processing and Communication Technologies

Control-A nd user-plane splitting in small cell architecture of 4G LTE-A

A theoretical model based on the generalized neuronal model with distributed delay (GNMDD) is proposed to generate multimodal/bimodal inter-spike interval (ISI) distribution. The distributed delay is assumed to be general in the sense that it is a linear combination of gamma distributed weak and strong memory kernels. It is found that the expected membrane potential in the subthreshold regime exhibits damped oscillatory behavior. This causes the ISI pattern to become bimodal/multimodal. Furthermore, the effect of external damped oscillatory current in the GNMDD model is investigated. Based on extensive simulation study of a set of coupled stochastic differential equations in the presence of a threshold, a vast amount of spiking data are generated. Using the non-parametric modeling approach, the optimal bin width of the histogram is obtained by using the Freedman-Diaconis rule. It is to be noted that, with the increasing amplitude of the damped oscillatory current, the multimodal ISI distribution changes to unimodal ISI distribution when the magnitude of external current reaches a critical value. It is found that the entropy also shows a sudden transition around the critical point. This phenomenon is akin to a phase transition. © 2018 IEEE.

World University root node

Computer Science and Engineering

IEEE Transactions on Nanobioscience

Suppression of multimodality in Inter-Spike interval distribution: Role of external damped oscillatory input

In the last few years the research activity in multifunctional composite materials and structures (MFCMS) is remarkably increased. This paper is a review of journal publications that are related to multifunctional composite materials and structures. MFCMS are meant for performing a variety of functions apart from the primary structural function which provides structural functions such as strength, stiffness, stability while non-structural functions provides energy harvesting, self-healing capability, sensing and actuation and sometimes acts as a protective layer etc. Many of the recent developments focused on the applications of MFCMS such as High Altitude Airship (HAA), morphing aircraft wings, energy harvesting, nanomaterials & nanostructures, smart structures, coupled field analysis, biomechanical etc. This paper also focused on the nonlinear mechanics of MFCMS because High Altitude Airship type of problems comes under geometrically and materially nonlinear case, so to analyse this type of problems one of the effective method called Variational Asymptotic Method is used. This method solves the problem by splitting the 3-D nonlinear problem into 1-D analysis through the thickness and 2-D nonlinear shell analysis. This paper concludes with a discussion of future scope and difficulties in design and analysis of multifunctional composite structures. © 2017 Elsevier Ltd.

Mechanical Engineering

Materials Today: Proceedings

A review of recent research on multifunctional composite materials and structures with their applications

There is an immense need for developing a simple, rapid, and inexpensive detection assay for health-care applications or monitoring environments. To address this need, a photonic crystal (PC)-based sensor has been extensively studied due to its numerous advantages such as colorimetric measurement, high sensitivity, and low cost. However, the response time of a typical PC-based sensor is relatively slow due to the presence of the inevitable upper residual layer in colloidal structures. Hence, we propose an ultra-fast responsive PC-based volatile organic compound (VOC) sensor by using a "nanoscale easy tear (NET) process" inspired by commercially available "easy tear package". A colloidal crystal-polydimethylsiloxane (PDMS) composite can be successfully realized through nanoscale tear propagation along the interface between the outer surface of crystallized nanoparticles and bulk PDMS. The response time for VOC detection exhibits a significant decrease by allowing the direct contact with VOCs, because of perfect removal of the residual on the colloidal crystals. Moreover, vapor-phase VOCs can be monitored, which had been previously impossible. High-throughput production of the patterned colloidal crystal-polymer composite through the NET process can be applied to other multiplexed selective sensing applications or may be used for nanomolding templates. © 2018 The Author(s).

Chemical Engineering

Fulltext

Scientific Reports

Ultra-fast responsive colloidal-polymer composite-based volatile organic compounds (VOC) sensor using nanoscale easy tear process

In this work two novel copolymers of Boron dipyrromethane (BODIPY) and Fluorene are designed, synthesized and their optoelectronics properties is reported. The polymers were designed to study the effect of the substituent at the meso position of BODIPY on the optoelectronic properties of the polymer. Changing the methyl group on the phenyl group at the meso position in the BODIPY subunit to trifluoromethyl group not only lowers the LUMO energy value but also improves the electron transport in the polymer. The polymers have also been used as electron transport material to fabricate all polymer solar cell and polymer photodetectors. © 2018 IEEE.

2018 4th IEEE International Conference on Emerging Electronics, ICEE 2018

Effect of meso substituent on Optoelectronic Properties in BODIPY based donor acceptor Copolymers

The fundamental characteristics of metal coatings that influence heat transfer are porosity and surface roughness. It is a challenge to analyze the porosity and surface roughness due to the inadequate amount of copper per coated area. In this study, a new approach to non-invasively determine the porosity of metal films utilizing a helium pycnometer and computed micro-tomography (CMT) is presented. Furthermore, a telescope-goniometer is used to measure the surface roughness. Experiments are conducted on four varieties of thin film samples coated with copper powder using wire flame and plasma thermal spray coating methods. The porosities of the thin films were determined to be between 39 and 43%. The thermal spray coating increased the hydrophobicity of the surface and the plasma coating created super-hydrophobic surfaces. The new approach establishes that the porosity of thin films can be non-invasively determined and may also be applied to a wide variety of coated surfaces. © 2018, The Author(s).

A New Approach to Compute the Porosity and Surface Roughness of Porous Coated Capillary-Assisted Low Pressure Evaporators

We report the effects of annealing in conjunction with CdCl2 treatment on the photovoltaic properties of CdTe/Zn0.1Cd0.9S thin film solar cells. CdTe layer is subjected to dry CdCl2 treatment by thermal evaporation method and subsequently, heat treated in air using a tube furnace from 400 to 500°C. AFM and XRD results show improved grain size and crystallographic properties of the CdTe film with dry CdCl2 treatment. This recrystallization and grain growth of the CdTe layer upon CdCl2 treatment translates into improved photo-conversion efficiencies of CdTe/Zn0.1Cd0.9S cell. The results of dry CdCl2 treatment were compared with conventional wet CdCl2 treatment. Photo-conversion efficiency of 5.2\% is achieved for dry CdCl2-treated cells in comparison with 2.4\% of wet-treated cell at heat treatment temperature of 425°C. © Indian Academy of Sciences.

Bulletin of Materials Science

Effect of annealing temperature and CdCl2 treatment on the photo-conversion efficiency of CdTe/Zn0.1Cd0.9S thin film solar cells

In recent years, biodiesel, as a renewable and environment-friendly fuel has emerged as one of the most investigated bio-fuel with a goal to decrease our dependence on petroleum fuels and reduce environmental pollution. The current commercial technique of biodiesel production via transesterification is constrained by high operating cost and energy requirements, long residence time and limited conversion due to equilibrium limitations. On the other hand, the process intensification using the micro-reactor technology demonstrated an excellent performance ascribed to short diffusion distance and high surface area-to-volume ratio that can lead to high heat and mass transfer rates and improved mixing compared to the conventional reactors. This review provides an overview of the current status of biodiesel production in micro-reactors. It includes various types of micro-reactors used in the production of biodiesel, factors affecting the biodiesel production (i.e., temperature, residence time, alcohol to oil molar ratio, micro-channel size, inlet mixer type, internal geometries, co-solvent, catalyst type and concentration). This review also includes the factors affecting the liquid-liquid flow patterns and application of micro-reactor technology in the purification of biodiesel. Some of the critical observations from this review are, 1) inlet mixer type, channel size, and internal channel geometry (zig-zag, omega, and tesla shaped channels) have shown a significant effect on mixing in micro-channels. 2) In case of base-catalyzed transesterification, the biodiesel yield was found to increase up to the reaction temperature of 60–65 °C. 3) Homogeneous alkaline catalyst (NaOH, KOH, CH3ONa) was preferred for the feedstock with low free fatty acid content (&lt;1 wt\%). However, an acid catalyst with high concentration, a significant amount of methanol and long reaction time were required for high free fatty acid feedstock (&gt;1 wt\%). Therefore, the current research is more focused on the investigation of heterogeneous catalysts in micro-reactors to develop an ecologically friendly process for the production of biodiesel. 4) Also, the reaction temperature and inlet mixer type had shown a significant effect on liquid-liquid flow patterns. This review also addressed the following literature gaps; a numbering-up technique to increase the throughput; catalyst development for high free fatty acid feedstock; continuous production of biodiesel in micro-reactors with in-line purification step to meet the energy demand and quality standards. © 2018 International Energy Initiative

Energy for Sustainable Development

Biodiesel production in micro-reactors: A review

A new approximate expression for the probability density function (pdf) of K-distribution is proposed. The approximate pdf is found to be in good agreement with the exact analytical closed-form expression over the desired range of scintillation index lying between 2 and 3. Employing the proposed pdf, the expression in respect of two of the QoS measures of fade probability and bit error rate (BER) valid under various modulation schemes is given. Using the generalised expression of BER, plots under ON-OFF keying and binary phase shift keying modulation schemes are shown. The resulting expressions provide a better understanding in contrast to the exact results obtained in terms of Meijer G functions. Numerical computations are carried out to demonstrate the efficacy of approximate results. © The Institution of Engineering and Technology 2018.

Physics

(SoNS) School of Natural Sciences

IET Communications

New approximation for pdf of K- distribution: Analytical study of QoS parameters in free space optical communication

This paper proposes a method for gesture classification based on Graph Fourier transform (GFT) coefficients. GFT coefficients are the projection of image pixel block onto the eigenvectors of a Laplacian matrix. This Laplacian matrix is generated from undirected graph, representing a spatial connectedness between each pixel within an image block. This work proposes a method for generating an undirected graph by using edge information of the image. Edge information of the image is obtained by average sum of absolute difference between the current pixel and its neighboring pixels by using an appropriate threshold. The resulting GFT based feature vector is formed by concatenating GFT coefficients of each block. The resultant feature vector is applied to linear Support Vector Machine (SVM) classifier to predict the gesture class. For NTU and Massey hand gesture datasets, threshold value 30 gives maximum prediction accuracy. We compare the results of the proposed GFT based descriptor approach with Karhunen-Loeve transform (K-LT) and Discrete Cosine transform (DCT) based descriptors on three different gesture datasets: NTU, Cambridge and Massey. Simulation results show that the proposed GFT based descriptor gives a comparable results with Karhunen-Loeve transform (K-LT) and Discrete Cosine transform (DCT) based descriptors for gesture classification. © 2017 IEEE.