Vignan University

About: Vignan University is a education organization based out in Guntur, Andhra Pradesh, India. It is known for research contribution in the topics: Control theory & CMOS. The organization has 1138 authors who have published 1381 publications receiving 7798 citations.

Determination of Stress and Deflection of Cantilever Beam for Various Cross-Sections

Abstract: A Cantilever beam is one, which is anchored at only end. A beam is a structural element that is capable of withstanding load primarily by resisting bending. There are different types of beams, like cantilever beam, simply supported beam and in that there will be different types of cross-sections, like rectangular, circular etc. In this present work we have taken a cantilever beam and three cross-sections are selected (Rectangular, circular, and T) and analysis was done and the stress and deflection of all the three cross-sections were found and tabulated. For carrying out the analysis Ansys workbench software was chosen.

Design of dual director short back fire antenna for UWB applicatios

Abstract: The design proposed in this paper is dedicated to increasing the gain of Short Back Fire Antenna (SBFA) in the 20% bandwidth. A SBFA consists of a round disc of two wavelengths diameter with a quarter wavelength rim. A dipole (or crossed simple) is mounted above the disc with quarter wavelength and a second small disc (disc 1) having half a wavelength diameter is located above the lower disc with a half wavelength. This modified version has a conical reflector with a rim, as well as an additional front disc of more than 15dB and the return loss will be less than −10dB. The designed antenna has a simple and compact construction and high mechanical and electrical characteristic. Hence, it is appropriate for the applications of Ultra Wide Band (UWB) and satellite communications. This proposed antenna presents the input impedance, radiation patterns return loss, VSWR, E-field, H-field current distributions using CST Microwave Studio Software.

Performance analysis of OQAM based GFDM 5G systems under line of sight fading scenarios

Abstract: As the world is moving towards everywhere and everything connected society, the fifth generation cellular systems is the leading technology to realize this dream. Generalized frequency division multiplexing (GFDM) is one of the physical layer waveform considered for 5G to overcome the deficiencies of the existing OFDM based 4G cellular systems such as Inter Carrier Interference (ICI) and Inter Symbol Interference (ISI). Already GFDM research proved that GFDM using Quadrature Amplitude Modulation (QAM) is more flexible and robust compared to the OFDM based LTE systems. In this paper, it is considered the performance of the Offset QAM based GFDM and the analysis of Symbol Error performance under various fading conditions. The performance of GFDM-OQAM system is evaluated for Outdoor fading profiles such as Highway Line of Sight (HLOS), Urban Approaching Line Of Sight (UALOS), and Rural Line of Sight (RLOS).

Effect of Substrate Temperature on the Growth of Molybdenum Trioxide Thin Films

Abstract: Molybdenum oxide is one of the most important inorganic material, which exhibits several phases, such as MoO3, MoO2, Mo4O11, Mo5O14, etc. Among them, molybdenum trioxide (MoO3) can crystallize in various phases, such as orthorhombic, monoclinic etc., which makes it useful for possible applications in chemical, electrical and electrochemical industries. In this work, MoO3 films were obtained by pulsed laser deposition by varying the substrate temperature from room temperature to 400°C. The thin films were deposited on fine cleaned glass substrates coated with fluorine tin oxide under a pressure of 10–5 mbar. X-ray diffraction patterns display two polymorphic phases of MoO3 (α and β), but no other phases are observed, and the structure changes from orthorhombic to monoclinic. The substrate temperature strongly influences the structure and surface topography. Morphological studies show the surface homogeneity, crack-free, layered structure and crystallinity of the films. The band gap of the obtained MoO3 thin films increases from 3.0 to 3.39 eV with increasing substrate temperature from room temperature to 400°C.

The Pursuit of Alachlor Herbicide Toxicity on Eisenia fetida and Its Biochemical Responses

Abstract: Alachlor is a chloroacetanilide herbicide, which is extensively used in agriculture globally. It is proposed that it is a carcinogen and an estrogen too. Earthworms are largely involved in increasing the soil fertility, and excess use of this herbicide may result in toxicity to burrowing organisms like earthworms. In this context, the current intent of the proposed work is to assess the toxicity of alachlor on Eisenia fetida. The lethal concentration (LC50) for alachlor was calculated on E. fetida as 251.28 ± 22.28 μg/cm2. The E. fetida were treated with LC50 concentration of alachlor for 24 h. Significant changes in morphology like whole body coiling, constricted body shape, fragmentation, and thinning of body and clitellar shrinkage were noticed in E. fetida exposed to alachlor for 24 h in comparison to their respective controls. Neurotoxicity of alachlor in E. fetida was evaluated by measuring the acetylcholinesterase (AChE) at 6, 12, 18, and 24 h respectively. Various biochemical biomarkers such as catalase (CAT), lipid peroxidation (LPO), and glutathione sulfotransferase (GST) were measured at 0, 6, 12, 18 and 24 h respectively. Significant differences in AChE, CAT, LPO, and GST were noted in both control and treated E. fetida at different time intervals. The current finding will be useful in laying the toxic effects of alachlor to non-target soil invertebrates.