Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

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VIT University

During surgical operations in the eye, metallic materials may come in contact with tears. These metals/alloys may undergo corrosion when they contact the tears. The corrosion resistance of a Ni –Cr alloy in artificial tears in the presence of excess of glucose and sodium chloride has been evaluated by electrochemical studies such as polarization study and AC impedance spectroscopy. It is observed that when the sodium chloride level or glucose level in tears increases, the corrosion resistance of Ni –Cr alloy in artificial tears is not affected. It is interesting to note that the corrosion resistance of Ni –Cr alloy in artificial tears rather increases. Hence when there is an increase in glucose level of sodium chloride level in tears, the surgical instruments may be of Ni –Cr alloy. © 2019, Russian Association of Corrosion Engineers. All rights reserved.

World University root node

Department of Communication Engineering

School of Electronics Engineering

Vellore Campus

Department of Manufacturing Engineering

School of Mechanical Engineering

Fulltext

International Journal of Corrosion and Scale Inhibition

Corrosion resistance of Ni–Cr alloy in artificial tears in the presence of excess of glucose and sodium chloride

Question Answering is one of the most common applications for data acquisition. Although the majority of text-mining applications strive to improve the user experience and the tools used to find appropriate answers, the problems still exist because the web content is constantly increasing. The Questions Classification (QC) task is one of the main tasks in improving the classification system is to classify types of questions in the text mining application. A large number of QC methods are introduced to help resolve classification problems, most of which are bag of words approaches. In this project, we propose a QC system that uses Parts of Speech (POS) Tagger and Named Entity Recognition (NER) Tagger from the Stanford core Natural Language Processing (NLP) to classify the questions correctly. We started by cleaning the data by removing the available labels in the questions then we proceed by tagging the questions by splitting words and tagging each and every words in the input question with the POS Tagger. After this step, we will convert them into a pattern without changing the structure of the question. Then we proceed by tagging the question with NER Tagger. Finally, we will do confirmation process for certain question types which is performed by confirming question type module to make the system work efficiently.

Computer Science

School of Computer Science and Engineering

Chennai Campus

International Journal of Innovative Technology and Exploring Engineering Regular Issue

Question Classification using a Rule based Model

In our paper, the impact of adaptive transmission schemes: (i) optimal rate adaptation (ORA) and (ii) channel inversion with fixed rate (CIFR) on the average spectral efficiency (ASE) are explored for free-space optical (FSO) communications with On–Off Keying (OOK), Polarization shift keying (POLSK), and Coherent optical wireless communication (Coherent OWC) systems under different turbulence regimes. Further to enhance the ASE we have incorporated aperture averaging effects along with the above adaptive schemes. The results indicate that ORA adaptation scheme has the advantage of improving the ASE performance compared with CIFR under moderate and strong turbulence regime. The coherent OWC system with ORA excels the other modulation schemes and could achieve ASE performance of 49.8 bits/s/Hz at the average transmitted optical power of 6 dBm under strong turbulence. By adding aperture averaging effect we could achieve an ASE of 50.5 bits/s/Hz under the same conditions. This makes ORA with Coherent OWC modulation as a favorable candidate for improving the ASE of the FSO communication system. © 2017 Elsevier B.V.

Optics Communications

Average spectral efficiency analysis of FSO links over turbulence channel with adaptive transmissions and aperture averaging

With the advancement of the product improvement, the size of the product is progressively developing to the degree that we can't hand it effortlessly. A few measurements are proposed to measure the multifaceted nature of programming in last a couple of years. This article goes for an extensive overview of the metric of programming multifaceted nature [2]. Hence we have used two developing method of calculating the metrics which are Pearson and Spearman. The advantages of using them and best method between them is identified by using an example. © 2017 IEEE.

Department of Digital Communications

School of Information Technology and Engineering

VIT Unitversity

2017 International conference of Electronics, Communication and Aerospace Technology (ICECA)

Analyzing the forest fire using correlation methods

Free Space Optics (FSO) communication technology with Multi-input and Multi-output (MIMO) and subcarrier intensity modulation (SIM) has captivated interests in research due the diversity gain offered by MIMO. Atmospheric turbulence and pointing errors are the major challenges that affect the FSO system performance. In this work, the FSO based 2×1 Alamouti scheme employing SIM and Q-PSK is analyzed and compared without using Alamouti scheme with Gamma-Gamma (GG) fading channel considering pointing error effects. We derived the closed form expressions for symbol error rate (SER) with Alamouti scheme under the effect of different atmospheric turbulence and pointing errors using moment generating function (MGF). As a result, the proposed system could achieve a high signal-to-noise ratio(SNR) gain of 27 dB over the without Alamouti scheme under moderate and strong turbulence regime. © 2017 IEEE.

2017 Innovations in Power and Advanced Computing Technologies (i-PACT)

Performance analysis of alamouti scheme in turbulence induced fading with pointing errors

The average spectral efficiency (ASE) is investigated for the free space optical (FSO) communications employing On-Off keying (OOK), Polarization shift keying (POLSK), and Coherent optical wireless communication (Coherent OWC) systems with and without pointing errors over the Gamma-Gamma (GG) channels. Additionally, the impact of aperture averaging on the ASE is explored. The influence of different turbulence conditions along with varying receiver aperture has been studied and analyzed. For the considered system, the exact average channel capacity (ACC) expressions are derived using Meijer G function. Results reveal that when pointing errors are introduced, there is a significant reduction in the ASE performance. The enhancement in the ASE can be achieved with an increase in the receiver aperture across various turbulence regimes and reducing the beam radius in the presence of pointing errors, but the rate of increment of ASE reduces with a larger diameter and it is saturated finally. The coherent OWC system provides better ASE performance of 49 bits/s/Hz at the average transmitted optical power of 5 dBm with an aperture diameter of 10 cm and 34 bits/s/Hz without and with pointing errors under strong turbulence respectively. © 2016 Elsevier B.V.

Aperture averaging effects on the average spectral efficiency of FSO links over turbulence channel with pointing errors

Free Space Optics (FSO) communication technology has attracted large attention because of its high data rates and security. FSO links experience disturbances due to atmospheric turbulence and pointing errors. The performance of the FSO system can be improved by adding an extra transmit aperture at the transmitter along with Alamouti scheme. In this work, the FSO based 2x1 Alamouti scheme is analyzed with a novel statistical channel model called Double-Generalized Gamma (DGG), which accurately describes turbulence-induced fading over a wide range of turbulence conditions. The main objective of this paper is to derive the symbol error rate (SER) of FSO system for M-PSK with Alamouti scheme under the effect of different atmospheric turbulence with and without pointing errors using moment generating function (MGF). The SER performance of the proposed scheme is compared without Alamouti scheme. We also compare the results of DGG with Gamma Gamma (GG) fading channel. The performance of DGG is observed to be more nearer to the physical conditions. Substantial gain is achieved by using 2x1 Alamouti scheme. © 2017 IAMOT.

International Journal of Microwave and Optical Technology

On the performance of alamouti scheme in double- generalized gamma fading FSO links with pointing errors

2015 SAI Intelligent Systems Conference (IntelliSys)

Applying regression models to calculate the Q factor of multiplexed video signal based on Optisystem

Free-space optical communication is utilized for transmitting data between the source and destination using light traveling through free space. In this paper, the modulation technique applied to the propagating light is linear polarization shift keying. An FSO system is simulated in Optisystem software using the aforementioned modulation technique under different weather conditions. The performance analysis of the system is carried out by examining minimum BER values and the corresponding transmission distance achieved with different specific attenuations. © 2006-2015 Asian Research Publishing Network (ARPN).

ARPN Journal of Engineering and Applied Sciences

Simulation research of free-space optical communication based on linear polarization shift keying modulation

The optical fiber has found great application in long distance communications, as light the medium of information transfer attenuates very less compared to electric pulses in cables. However the major issues that limit efficiency are chromatic dispersion and non-linear effects. Fiber Bragg Grating (FBG) is widely used as a component to compensate dispersion on account of its low insertion loss. This paper provides a method of using a combination of FBG as a dispersion compensator and Bessel filter to improve the Q factor of the system and also reduce the noise figure. A 10 Gb/s NRZ pulse is launched into the fiber and the performance of the system is evaluated using Optisystem simulator. The Q factor of the system is then investigated with and without use of Bessel filter. The simulation is analysed with respect to input power, fiber length, and attenuation coefficient. © 2006-2015 Asian Research Publishing Network (ARPN).

Performance analysis of optical transmission system using FBG and bessel filters

Free Space Optical Communication (FSO) is the communication system which uses optical signal to establish a direct link between two points. With increase in the use of digital data and requirement of high speed communication it has become necessary that the reliable and high speed communication system should be developed in order to provide uninterrupted service. Use of wireless signals in every type of communication has crowded the space and often results in increased interference. These all issues can be solved with the development of an efficient FSO. This paper focuses on the development an efficient FSO system for short range communication purpose using multi-laser beams and efficiency of FSO network under different weather conditions. © Research India Publications.

International Journal of Applied Engineering Research

Improving the efficiency of FSO communication system with multi-laser beams

In this paper, we have demonstrated an optical radio-frequency signal generation and single sideband modulation technique for Radio-over-fiber (RoF) systems. This technique uses stimulated Brillouin scattering interaction. We used a dual-electrode Mach-Zender modulator to realize Double side band modulation on one part and on the other part, a fiber Bragg grating (FBG) is employed to enhance the optical carrier suppression ratio and reduce the effect of residual optical harmonics. We also studied the effect of tunable data rate on BER and power penalty which is less than 1. 5 dbm. The Undesired suppression sideband ratio, USSR (ratio of amplified sideband and attenuated sideband) and power penalty is examined for the SBS and OTSSB techniques and results are presented. © Research India Publications.

Department of Embedded Technology

Analysis of single side band generation techniques using stimulated Brillouin scattering and OTSSB for 1 Gbps ROF downlink

The objective of this paper is to design a hybrid fiber wireless (Fi-Wi) access network. This has been achieved using PDM-RZ-DPSK transmission technique in the optical fiber network and Quadrature Amplitude Modulation (QAM) in the wireless access network. This is an attempt to improve the spectral efficiency and increase the end user data rate by using PDM. This technique minimizes the sensitivity to depolarization and shows reduced intersymbol interference as the eye diagram is clear and open. The transmitted and received data at the input and output of wireless channel is also coherent to each other showing minimal error. © Research India Publications.

40-Gbps PDM-RZ-DPSK transmission with wireless integration

Department of Micro and Nanoelectronics

2013 International Conference on Emerging Trends in Communication, Control, Signal Processing and Computing Applications (C2SPCA)

A high performance 2-dimensional VLSI architecture for H.264/AVC Variable Block Size integer motion estimation

This paper addresses the existing PON system and its various drawbacks. The main problem in the existing PON system is its scalability and absence of dynamism. When PON system is integrated with Wavelength Division Multiplexing (WDM)/Time Division Multiplexing (TDM), the performance of the network increases drastically. An attempt has been made to develop different PON architectures and to show how these concepts can be applied on real time basis to enhance the performance of the present PON system. Also a comparative study between the different PON networks has been made and their usability in various fields with different requirements has been assessed. An architecture for dynamic WDM/TDM PON system, is designed which will be a tremendous break through when implemented on real time basis. © Research India Publications.