(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

As humans spend around 90\% of their time indoors, Indoor Air Quality (IAQ) is a subject of major concern for the physical and mental well-being of humans. According to the United States Environment Protection Agency (US EPA), even in centrally air-conditioned buildings, indoor air is much more polluted than outdoor air, mainly due to changes in occupancy patterns, old or ill-maintained ventilation systems and dust. Therefore, it becomes important to measure and analyze IAQ. In this work, an end to end IoT system has been developed to sense and analyze indoor environmental parameters: temperature, humidity and carbon dioxide. These sensed values are then used to compute Predicted Mean Vote (PMV) and Ventilation Rate (VR), which are further combined to develop an indicator of the current air quality and thermal comfort index, the Air Quality and Comfort Indicator (AQCI), using fuzzy inference. © 2019 IEEE.

Computer Science and Engineering

International Symposium on Advanced Networks and Telecommunication Systems, ANTS

AQCI: An IoT Based Air Quality and Thermal Comfort Model using Fuzzy Inference

In this communication, the performance evaluation has been discussed for various kinds of photovoltaic (PV) technologies which has integrated to solar air collector with drying system. Mathematical modelling has been carried out for photovoltaic thermal air collector (PVTAC) with dryer. On the basis of mathematical model, energy analysis has been carried out for different types of partially covered PV technologies (namely, c-Si, p-Si, a-Si, CdTe and CIGS) air collector. CIGS has been found to be the best PV technology for large systems in terms of minimum embodied energy and payback period. © 2019 Elsevier Ltd. All rights reserved.

World University root node

Mechanical Engineering

Materials Today: Proceedings

Performance evaluation of different types PV materials for PVTAC with solar drying system

During a short circuit, the transformer's inner winding, which is supported by the inner support structure, may fail due to the buckling phenomenon. This occurs due to the generation of large radially inward electromagnetic force on the inner winding. In the literature, the effect of the number of axial supporting spacers on the critical buckling stress is reported, but there is no investigation about the effect of their circumferential width on the value of the critical buckling stress. In this letter, the effect of the circumferential width of the axial supporting spacers on the value of critical buckling stress of the transformer inner winding has been investigated. An algorithm has been given to calculate the critical buckling stress of the inner winding. A case study has been taken from the published work, and by varying the width of the spacers, the factor of safety against buckling has been determined. © 1986-2012 IEEE.

Electrical Engineering

IEEE Transactions on Power Delivery

Effect of Width of Axial Supporting Spacers on the Buckling Strength of Transformer Inner Winding

Photoconductive antennae are one of the most common sources of terahertz radiation. Although extensive experimental and simulation work has been done to analyze the radiated fields, very limited theoretical analysis has been done to build elegant and compact models. This work presents the derivation of the radiated fields from a photoconductive antenna incorporating the effect of the semiconductor substrate. Additionally, an improved model of the semiconductor carrier dynamics has been proposed to analyze the radiation characteristics of the photoconductive antenna. The proposed carrier dynamics includes a novel analysis of the transient behavior of the substrate temperature and its effect on the parameters of the substrate material. It also incorporates the effect of the lifetime, polarization and velocities of the carriers as well as the effects of the radiated near zone fields and antenna geometry. The derived formulae and the proposed carrier dynamics model have been validated by comparing the results with the available experimental results in the literature. It has been found that the analytically calculated results closely follow the experimental results reported in the literature. © 2019 IOP Publishing Ltd.

Semiconductor Science and Technology

Radiation field analysis of a photoconductive antenna using an improved carrier dynamics

In this letter, we study a few properties of Complex Conjugate Pair Sums (CCPSs) and Complex Conjugate Subspaces (CCSs). Initially, we consider an LTI system whose impulse response is one period data of CCPS. For a given input x(n), we prove that the output of this system is equivalent to computing the first order derivative ofx(n).Further, with some constraints on the impulse response, the system output is also equivalent to the second order derivative. With this, we show that a fine edge detection in an image can be achieved using CCPSs as impulse response over Ramanujan Sums (RSs). Later computation of projection for CCS is studied. Here the projection matrix has a circulant structure, which makes the computation of projections easier. Finally, we prove that CCS is shift-invariant and closed under the operation of circular cross-correlation. © 2019 IEEE.

Fulltext

IEEE Signal Processing Letters

On complex conjugate pair sums and complex conjugate subspaces

The paper analyses four types of DG (distributed generators) for their optimal placement in primary distribution system. They are sited and sized optimally to obtain maximum loss reduction. The ultimate objective of the adopted work in this paper is to identify the size and location of distributed generators for their placement in primary distribution network and to justify the economics of these placements. To serve the purpose, an analytical method is used in this paper for determination of sizes and sites for four DG types. The analytical method is considered suitable for the analysis purpose in proposed work. The paper presented a comprehensive analysis for four types of DGs for their placement in primary distribution system. The type 1 DG is capable of delivering real power only whereas type 3 DG is capable of providing real as well as reactive power to the distribution network. Out of other two types, type 2 can deliver only the reactive power whereas type 4 supplies active power but at the same time it consumes reactive power. The paper compares the economic feasibility of placement of four DG types in primary distribution system. © BEIESP.

International Journal of Innovative Technology and Exploring Engineering

Optimal integration of distributed generation in primary distribution system and its economics

Airships are fast gaining popularity as one of the most prominent modes of surveillance, reconnaissance and providing connectivity in remote areas. These airships work on the Archimedes' principle, and employ gases which are lighter than air to stay afloat in the atmosphere. These gases are the most critical and costly support element for the usage of such airships as the permeation of these gases through the envelope material limits the flight duration of the airship and further increases the cost associated with transporting and refilling of the airship, thereby limiting its utility. Engineering the material of the envelope, so as to be able to minimize the leakage of gas, becomes the most important challenge for engineers designing the airships. The traditional experimental techniques used to analyse the permeation through the laminate are known to be extremely sensitive to minor variations in temperature and pressure and involve specialized equipment, time and money. This paper proposes and discusses alternate Computational Fluid Dynamics based 2D and 3D approaches to analyse the permeation of the gas through the envelope material, particularly for high altitude airship applications. In addition to this, this paper proposes a method to determine the best suited material for the airship envelope through a qualitative and quantitative permeation analysis of different combinations of material options. © 2019 Author(s).

AIP Conference Proceedings

Analysis and retardation of helium permeation for high altitude airship envelope material

India is an agriculture prominent country. Scientist and researchers are continuously working for betterment of agriculture processes. From the research, it was found that there is a loss of power and resources in irrigation process. Present manuscript consist of proposed model which utilizes renewable energy (solar energy) to operate irrigation process which results in better handling within limited resources. Proposed system consist of moisture sensing device in the field that provide convenience to farmer by supporting them in automation at very minute energy. This proposed design uses polycrystalline photovoltaic solar panel to charge the battery and this battery provide power supply to operate the model. © Published under licence by IOP Publishing Ltd.

IOP Conference Series: Materials Science and Engineering

Investigation of Automatic Solar Irrigation Model

An IoT end to end system has been developed in this work to collect relative humidity (RH), CO2 concentration and occupant count of a University classroom. The RH and CO2 data has been used to compute estimates of student occupancy using regression based estimation models. Multiple linear and quantile regression models have been explored for occupancy estimation by using RH, CO2, and both RH as well as CO2 concentration respectively. The estimation performance of these models has been compared by using mean absolute percentage error. The quantile regression based models have been found to be the most accurate with a mean absolute percentage error of 2.47\%. © 2019 IEEE.

2019 IEEE 16th India Council International Conference, INDICON 2019 - Symposium Proceedings

IoT-based occupancy estimation models for indoor non-residential environments

The present work is focused on experimental investigations of gas-liquid flows in T-junction splitting distributor for parallel micro-channels. The tree type T-junction splitting distributor was designed with four successive T-junctions (T1, T2, T3 and T4) that are linked in series to split a single main channel into four parallel channels. The design strategy was adopted from Adamson et al. [1], Hoang et al. [2], and modified with a combination of micro and milli channel dimensions and reduction in width of the successive blocks by a factor of 20.5 to ensure the flow uniformity in terms of constant relative lengths (Lbubble/slug/Wchannel) of bubbles/slugs in all the blocks. Experiments were performed to study the effect of Qoil (=3, 6, 8, 10, 12 and 16 ml/min) at fixed Qair (=3 ml/min) on formation dynamics of bubbles/slugs at 1st T-junction and splitting mechanisms of bubbles/slugs at the successive T-junctions, the corresponding relative lengths of bubbles/slugs and flow regimes. The results obtained from the present work showed that, followed by formation of parent gas slug at T1 the splitting of gas slug occurred at the successive T-junctions (T2, T3 and T4). Three types of splitting mechanisms were observed such as obstructed (Qoil = 3, 6, 8, 10 ml/min; 0.0023 ⩽CaBlock-I ⩽0.0050), partially obstructed (Qoil = 12 ml/min; CaBlock-I = 0.00585) and non-obstructed (Qoil = 16 ml/min; CaBlock-I = 0.0074). It was observed that asymmetry of the splitting at the successive T-junctions was reduced for Qoil ⩾10 ml/min (CaBlock-I ⩾0.0050). No splitting of bubble was observed for Qoil &gt; 16 ml/min. However, it was also found that the proposed design strategy of splitting distributor for parallel micro-channels yields an almost constant relative lengths of bubbles/slugs (flow uniformity) in all the blocks for Qoil ⩾8 ml/min. © 2018 Elsevier B.V.