Heritage Institute of Technology

About: Heritage Institute of Technology is a based out in . It is known for research contribution in the topics: Steganography & Support vector machine. The organization has 581 authors who have published 1045 publications receiving 8345 citations.

Performance and flow analysis of an elliptic bladed Savonius-style wind turbine

Abstract: This paper describes the results of a three-dimensional numerical investigation conducted on an elliptic bladed Savonius-style wind turbine (SSWT) and the flow field around it. The investigation is also enriched by the comparison of the performance and flow characteristics of this turbine to that of a conventional semicircular bladed SSWT. Unsteady Reynolds-Averaged Navier-Stokes equations are solved using a k-ω shear stress transport turbulence model under dynamic conditions. The numerical results indicate the highest power coefficient (CP) of 0.25 for an elliptic bladed SSWT in comparison with 0.21 for a semicircular bladed SSWT. Furthermore, the computational findings are strengthened by the wind tunnel experiments. From both studies, better torque and power characteristics are obtained with the elliptic bladed turbine in comparison with the semicircular bladed turbine. The deviation of computational results from experimental findings for both kinds of turbines is studied here. The flow field in the vicinity of the blades for both the SSWTs has been studied and compared using the parameters, namely velocity, pressure, and turbulent intensity.

Performance Evaluation of Free Vibration of Laminated Composite Stiffened Hyperbolic Paraboloid Shell Panel with Cutout

Abstract: The paper considers free vibration characteristics of stiffened composite hyperbolic paraboloid shell panel with cutout in terms of natural frequency and mode shapes. A finite element code is developed for the purpose by combining an eight noded curved shell element with a three noded curved beam element. The size of the cutouts and their positions with respect to the shell centre are varied for different edge conditions of cross-ply and angle-ply laminated shells. The effects of these parametric variations on the fundamental frequencies and mode shapes are considered in details to conclude a set of inferences of practical engineering significance. Notations a ,b length and width of shell in plan / / , a b length and width of cutout in plan bst width of stiffener in general bsx, bsy width of x and y stiffeners respectively Bsx, Bsy strain displacement matrix of stiffener elements dst depth of stiffener in general dsx, dsy depth of x and y stiffeners respectively {de} element displacement esx, esy eccentricities of x and y -stiffeners with respect to shell mid-surface respectively E11, E22 elastic moduli G12, G13, G23 shear moduli of a lamina with respect to 1, 2 and 3 axes of fibre h shell thickness Mx, My moment resultants Mxy torsion resultant np number of plies in a laminate N1-N8 shape functions Nx, Ny inplane force resultants Nxy inplane shear resultant Qx, Qy transverse shear resultant Rxx, Ryy, Rxy radii of curvature and cross curvature of shell respectively u, v, w translational degrees of freedom x, y, z local co-ordinate axes X, Y, Z global co-ordinate axes zk distance of bottom of the kth ply from mid-surface of a laminate α,β rotational degrees of freedom ex, ey inplane strain component γxy ,γxz, γyz shearing strain components ν12, ν21 Poisson’s ratios ξ, η, τ isoparametric co-ordinates ρ density of material International Journal of Engineering and Technologies Submitted: 2016-02-09 ISSN: 2297-623X, Vol. 7, pp 1-24 Accepted: 2016-03-22 doi:10.18052/www.scipress.com/IJET.7.1 Online: 2016-05-16 © 2016 SciPress Ltd., Switzerland SciPress applies the CC-BY 4.0 license to works we publish: https://creativecommons.org/licenses/by/4.0/ σx, σy inplane stress components τxy, τxz, τyz shearing stress components ω natural frequency ω non-dimensional natural frequency ( ) 2 / 1 2 22 2 / h E a ρ ω = Introduction Composite shell structures are extensively used in aerospace, civil, marine and other engineering applications. In practical civil engineering applications, the necessity of covering large column free open areas is often an issue. It is advantageous to use thin shells instead of flat plates to cover large column free open spaces as in airports, parking lots, hangers, and the like. Such areas in medical plants and automobile industries prefer entry of north light through the roofing units. Quite often, to save weight and also to provide a facility for inspection, cutouts are provided in shell panels. In practice the margin of the cutouts must be stiffened to take account of stress concentration effects. In civil engineering construction, conoidal hyperbolic paraboloid (among the anticlastic) and elliptic paraboloid (among the synclastic) shells are used as roofing units to cover large column free areas. The hyperbolic paraboloid shells are aesthetically appealing although they offer less stiffness than other doubly curved shells. Now-a-days, civil engineers use laminated composites to fabricate these shell forms as the high specific stiffness and strength properties of these materials result in less gravity forces and mass-induced forces (seismic force) on the laminated shells compared to their isotropic counterparts. All these taken together reduce the foundation costs to a great extent. Realizing the importance of laminated composite doubly curved shells in the industry, several aspects of shell behaviour such as bending, buckling, vibration, impact etc. are being reported by different researchers. The present investigation is however, restricted only to the free vibration behaviour of composite stiffened hyperbolic paraboloid shell panels with cutout. No wonder a number of researchers are working to explore different behavioral aspects of laminated doubly curved shells. Researchers like Ghosh and Bandyopadhyay [1], Dey et al. [2, 3], Chakravorty et al. [4, 5] reported static and dynamic behaviour of laminated doubly curved shells. Later Nayak and Bandyopadhyay [6-8], Das and Chakravorty [9-12] and Pradyumna and Bandyopadhyay [13, 14] reported static, dynamic and instability behaviour of laminated doubly curved shells. Application of doubly curved shells in structures often necessitates provision of cutouts for the passage of light, service lines and also sometimes for alteration of the resonant frequency. The free vibration of composite as well as isotropic plate with cutout was studied by different researchers from time to time. Reddy [15] investigated large amplitude flexural vibration of composite plate with cutout. Malhotra et al. [16] studied free vibration of composite plate with cutout for different boundary conditions. One of the early reports on free vibration of curved panels with cutout was due to Sivasubramonian et al. [17]. They analysed the effect of cutouts on the natural frequencies of plates with some classical boundary conditions. The plate had a curvature in one direction and was straight in the other. The effect of fibre orientation and size of cutout on natural frequency on orthotropic square plates with square cutout was studied using Rayleigh-Ritz method. Later Sivakumar et al. [18], Rossi [19], Huang and Sakiyama [20] and Hota and Padhi [21] studied free vibration of plate with various cutout geometries. Chakravorty et al. [22] analysed the effect of concentric cutout on different shell options. Sivasubramonian et al. [23] studied the effect of curvature and cutouts on square panels with different boundary conditions. The size of the cutout (symmetrically located) as well as curvature of the panels is varied. Hota and Chakravorty [24] published useful information about free vibration of stiffened conoidal shell roofs with cutout. Later Nanda and Bandyopadhyay [25], Kumar et al. [26] studied the effect of different parametric variation on free vibration of cylindrical shell with cutout using first order shear deformation theory (FSDT) and higher order shear deformation theory (HYSD) respectively. 2 Volume 7

A New Scheme for Determination of Respiration Rate in Human Being using MEMS Based Capacitive Pressure Sensor: Simulation Study

Abstract: In this paper, a MEMS based capacitive nasal sensor system for measuring Respiration Rate (RR) of human being is developed. At first two identical diaphragm based MEMS capacitive nasal sensors are designed and virtually fabricated. A proposed schematic of the system consists of signal conditioning circuitry alongwith the sensors is described here. In order to measure the respiration rate the sensors are mounted below Right Nostril (RN) and Left Nostril (LN), in such a way that the nasal airflow during inspiration and expiration impinge on the sensor diaphragms. Due to nasal airflow, the designed square diaphragm of the sensor is being deflected and thus induces a corresponding change in the original capacitance value. This change in capacitance value is to be detected by a correlated- double-sampling (CDS) capacitance-to-voltage converter is designed for a precision interface with a MEMS capacitive pressure sensor, followed by an amplifier and a differential cyclic ADC to digitize the pressure information. The designed MEMS based capacitive nasal sensors is capable of identifying normal RR (18.5±1.5 bpm) of human being. The design of sensors and its characteristics analysis are performed in a FEA/BEA based virtual simulation platform. Index Terms— MEMS capacitive nasal sensor, diaphragm deflection, respiration rate (RR), oscillator, sensitivity, Finite Element Analysis, Boundary Element Analysis.

Optimized Multi - Layer Hierarchical Network Intrusion Detection System with Genetic Algorithms

Abstract: The number of connected devices on the Internet has exceeded 31 billion devices in 2018 and it is forecasted that this number will exceed 50 billion by the year 2020. One the other hand, malicious software and network attacks are raising on an alarming rate. It is estimated that more than 230,000 new malware are produced daily and over 53,000 new Cryptoware malware engines are detected as well. This proliferation in security attacks constitutes a great challenge for Intrusion Detection Systems (IDS), in particular, in detecting modern attacks. In this paper, a multi-layer hierarchical Network Intrusion Detection System (NIDS) is proposed with the aim to improve the overall detection performance of the IDS for detecting modern attack types. The proposed multi-layer NIDS utilizes multiple models of machine learning algorithms in a hierarchical architecture in addition to using evolutionary computing, namely Genetic Algorithms, to tune the configurations of the neural network models used in the first layer. A modern dataset (i.e. CICIDS-2017) is used to evaluate the proposed approach, which contains several modern attacks. The results showed that the proposed multi-layer system significantly improved on the error generalization metrics.

E-waste Inventorisation for Sustainable Smart Cities in India: A Cloud-based Framework

Abstract: The expansion of the electronics market, increased demand, short cycles of innovation, cunning marketing gimmick and buying capacity of consumers; the lifespan of electronic items are reducing. End-of-Life (EoL), popularly known as e-waste has become a big environmental menace worldwide. Global e-waste generation reached 53.6 million metric tons in 2019 from 41.8 million metric tons in 2014. India generated about 3.28 million metric tons of e-waste in 2019. However, the generation data might not be the same in reality in a country like India. The e-waste data is calculated from the electronics sales data. In India, the sales data is not properly obtained as no proper record is maintained and hence rough estimations are carried out. With the rise of the e-commerce sector nearly 26 percent electronic items are sold online in India. While offline electronics sales can be estimated from the associated Goods and Sales Tax (GST) data. E-waste management in India has geared up in the last 5 years and it is an important aspect for sustainable smart cities. With India promoting a smart city mission and targeting to reach the SDGs, it important to develop a system that can record the online as well as offline sales data and contribute in creating an e-waste inventory. An e-waste inventory for any country will be beneficial for further analysis. In this study, we propose a cloud-based framework for keeping record of electronics item sales data primarily from the e-commerce sector as well as from offline sales. The developed framework will be helpful to the researcher and it is expected to be a prima-facie for developing national e-waste inventory for any country.