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: Computer science & Control theory. The organization has 1138 authors who have published 1381 publications receiving 7798 citations.

An innovative approach to battery management and propulsion system of electric/hybrid electric vehicle

Abstract: There is a growing interest in electric and hybrid electric vehicles (HEVs) due to environmental concerns and fuel deficiency. This paper proposes a novel approach to battery charge indication and propulsion system of electric/HEV. The vehicle dynamics are studied to find an optimal torque–speed profile for the electric propulsion system. The results reveal that the vehicle operational constraints, such as initial acceleration and grade, can be met with minimum power rating if the HEV is operated in the constant power region. The proposed system is analysed using MATLAB software and the results are used in designing a physical model of a vehicle.

Characterization of novel composites from polybenzoxazine and granite powder

Abstract: The potential of using granite dust as reinforcement into polybenzoxazine matrix was investigated. In this article, novel granite powder waste-reinforced bisphenol-A aniline-based benzoxazine composites were prepared using solution blending technique by varying the content of granite powder from 10 to 40 wt%. The effect of the granite powder content on the thermal, structural, dimensional, and morphological properties of granite powder/polybenzoxazine composites have been investigated. Thermogravimetric analysis (TGA) was performed on the composite samples. Char yield of the composites increased from 44.55 to 67.70% for increasing filler content from 10 to 40wt%, whereas 22% for pure polybenzoxazine. The maximum weight loss temperatures of the composites were analyzed from derivative of thermogravimetric analysis (DTG). Limiting oxygen index (LOI) values also increased as granite powder content increased. Structural properties of benzoxazine, polybenzoxazine, and composites were observed with Fourier-transform infrared spectroscopy (FTIR). Dimensional stability of the composites was investigated through the water absorption test up to 30 days. The composites exhibited zero percent water absorption. Micro-hardness of the composites increased from 17.45 to 78.66% for increasing filler content from 10–40 wt% when compared with pristine polybenzoxazine. The morphological analysis using scanning electron microscopy (SEM) showed the distribution of filler, aggregate formation, compatibility between polybenzoxazine and granite powder. Overall, the importance of using granite powder waste as reinforcement in polybenzoxazine composites revealed from results of the structural, dimensional, and morphological analysis along with the improvement in thermal properties and micro-hardness.

Low Power, High Performance PMOS Biased Sense Amplifier

Abstract: Sense amplifiers plays a significant role in terms of its recital, functionality and reliability of the memory circuits. In this paper two new circuits have been proposed. The proposed circuit is PMOS biased sense amplifier, which provides very high output impedance and has reduced sense delay and power dissipation. As such, the proposed circuit performs the identical operations as that of conventional circuits but with the reduced the sense delay and power consumption. The suggested sense amplifiers overall performance have been simulated and examined using Cadence virtuoso with gpdk 180 nm library parameters.

Effective materials in the photocatalytic treatment of dyestuffs and stained wastewater

Abstract: Nowadays organic dyes are one of the leading groups of contaminants discharged into the environment, specifically from the textile industry. These are highly toxic in nature and detrimental towards living organisms and human beings; thus, adequate treatment of these hazardous dyes prior to discharge into the environmental body is essential. Several techniques have been exploited towards resolving this problem like physical, chemical, and biological means. Presently, photocatalysis is one of the advanced oxidation processes generally carried out under irradiation of light and appropriate photocatalytic materials. Heterogeneous photocatalysis has several advantages like ecofriendly in nature, economical, and efficient to degrade various dyes or organic pollutants present in waste effluent. Numerous photocatalysts along with modified or composite photocatalysts are used for the treatment of textile-effluent containing dye components. Titanium dioxide (TiO2) appears to be the most promising component and numerous modified versions of TiO2 provide enhanced photocatalytic activity on dye degradation. This chapter highlights the different conventional techniques for the removal of dyestuffs textile effluents, along with the detailed discussion on the photocatalysis process. The removal of several dye components through photocatalysis has also been discussed in this chapter.

Novel VLSI architecture for real time medical image segmentation

Abstract: Image segmentation plays an important role in the processing of medical images. Segmentation of medical images is a challenging task due to the poor image contrast and the diffusion of organs or tissue boundaries. Due to the emergence of new trends in the engineering technologies many medical diagnosis methods are automated using the image processing principles. Hence in this paper hardware implementation of segmentation of brain tumors is carried out using Xilinx System Generator (XSG) and FPGA. It results in greater performance, less design time and cost than the existing programmable Digital Signal Processors (DSPs) or than even PCs with coprocessors due to lot of parallelism and pipelining. Use of XSG for medical image processing applications effectively reduces the intricacies existing in architecture design and also provides additional feature of hardware co-simulation.