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.

Low Distortion Resource Allocation in NOMA based Cognitive Radio Networks

Abstract: To meet the demands of future generation wireless communications, Non-Orthogonal Multiple Access (NOMA) and Cognitive Radio (CR) are emerging technologies. In exchange of data over the wireless channels in these communications, interference is one of the major constraints in offering optimal service. The optimum utilization of resources depends on the accuracy of sensing, appropriate threshold selection, and proper resource allocation. In CR-NOMA cooperative relaying with fixed threshold was proposed for spectrum sharing in the existing works. The value of threshold plays a key role in decision making and a fixed value of the threshold is not an optimal solution for the dynamic channel environment. In addition to that maximum rate is allocated when the system meets interference, power, and rate constraints. But the accuracy of data reception was not considered. The loss of information in such a system has a greater impact on the overall performance of the system. To optimize the resource allocation in CR-NOMA with cooperative relaying, Quality Assured Resource Allocation (QARA) is proposed in this paper, where signal scaling, shaping, and probability of detection parameters are considered for defining the dynamic threshold and QoS monitoring is performed to assure accurate data communication. Here the bit error rate is calculated and the distortion is minimized by using the Lagrange Optimization method, which results in improved throughput. Simulation results indicate that the proposed system QARA outperforms the existing approaches.

Strategies to Adopt Information Technology in SMEs

Abstract: Small and Medium sized Enterprises (SME) play an important role in economic development of a country. Several theories obscure on connection between information technology, economic development and social change. Almost all agree on the importance of information and communication technology adoption in SME, while the importance of SME as an engine to economic growth is well acknowledged worldwide. Information technology, particularly the Internet is having a significant impact on the operations of SME and it is claimed to be essential for the survival and growth of nation’s economies in general and SME in particular. Information Technology (IT) adoption is an important field of study in a number of areas, which include small and medium-sized enterprises (SMEs). Due to the numerous advantages of IT, SMEs are trying to adopt IT applications to support their businesses. IT adoption by SMEs differs from larger organizations because of their specific characteristics, such as resources constraints. The size and importance of the SME sector varies from country to country. The last few decades have seen an increasing recognition of the role it plays in industrial developing countries. SME sector fulfils its potential role in contributing to a healthy economy.

Mathematical Simulation of Cavitation with Column Separation in Pressurized Pump Pipeline Systems

Abstract: Hydraulic transient analysis is important in design stage as well as the execution stage of pipeline systems for diagnosis of problems arises due to pipe burst, pipe collapses and leakages. The calculations necessary to analyse transient conditions must be very precise, more realistic and less time consuming. To fulfill this objective, a suitable mathematical model incorporating different components that simulates the real physical phenomenon is the need of hour. In this paper, column separation model called Discrete Vapour Cavitation Model (DVCM) is described and applied to a reference problem that consists of pump pipeline system. The calculations of this model are compared with calculations of the reference problem by conventional Method of Characteristics (MOC) approach. The results show that MOC could not able to capture the real physical phenomenon of cavitation with water column separation due to drawbacks in basic modelling.