Thapar University

About: Thapar University is a education organization based out in Patiāla, Punjab, India. It is known for research contribution in the topics: Computer science & Cloud computing. The organization has 2944 authors who have published 8558 publications receiving 130392 citations.

Investigation of rare earth particulate on tribological and mechanical properties of Al-6061 alloy composites for aerospace application

Abstract: Current research work emphasis on the development of rare earth particulate (REP) reinforced hybrid aluminium matrix composites processed by stir casting route. The weight percentage of CeO2 as rare-earth particulate varied from 0.5 wt% to 2.5 wt% and SiC /Al2O3 varied from 2.5 wt% to 7.5 wt%. The presence of rare earth particulate helps in grain refinement of the matrix with well defined grain boundaries is seen via Electron Backscatter Diffraction (EBSD) analysis. The Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD) and Energy Dispersive Spectroscopy (EDS) examination were used to characterize the prepared samples of Al-6061 hybrid composites. Porosity analysis, Vickers microhardness, tensile behavior, flexural strength and impact strength of the hybrid composites improved significantly with the addition of rare earth particulate. The flexural strength of the Al-6061 hybrid composites is found to be increased upto 44.76% by increased weight percentage of rare earth oxide phase. The optimum quantity of CeO2 as RE that favours the better tribological and mechanical characteristics of aluminium hybrid composites was found to be 2.5 wt%. The results of wear tests showed an improvement of wear rate around 87.28% when compared to Al-6061 alloy with the addition of 2.5 wt% of CeO2. Finally, the worn out surface of the hybrid composites is examined with the help of scanning electron microscope to understand the wear mechanism of the composites for aerospace application.

Binary whale optimization algorithm and its application to unit commitment problem

Abstract: Whale optimization algorithm is a novel metaheuristic algorithm that imitates the social behavior of humpback whales. In this algorithm, the bubble-net hunting strategy of humpback whales is exploited. However, this algorithm, in its present form, is appropriate for continuous problems. To make it applicable to discrete problems, a binary version of this algorithm is being proposed in this paper. In the proposed approach, the solutions are binarized and sigmoidal transfer function is utilized to update the position of whales. The performance of the proposed algorithm is evaluated on 29 benchmark functions. Furthermore, unpaired t test is carried out to illustrate its statistical significance. The experimental results depict that the proposed algorithm outperforms others in respect of benchmark test functions. The proposed approach is applied on electrical engineering problem, a real-life application, named as “unit commitment”. The proposed approach uses the priority list to handle spinning reserve constraints and search mechanism to handle minimum up/down time constraints. It is tested on standard IEEE systems consisting of 4, 10, 20, 40, 80, and 100 units and on IEEE 118-bus system and Taiwan 38-bus system as well. Experimental results reveal that the proposed approach is superior to other algorithms in terms of lower production cost.

Simulation type functions and coincidence points

Abstract: In this paper, we obtain some sufficient conditions for the existence and uniqueness of point of coincidence by using simulation functions in the context of metric spaces and prove some interesting results. Our results generalize the corresponding results of [5, 8, 13, 14, 16] in several directions. Also, we provide an example which shows that our main result is a proper generalization of the result of Jungck [American Math. Monthly 83(1976) 261-263], L-de-Hierro et al. [J. Comput. Appl. Math 275(2015) 345-355] and of Olgun et al. [Turk. J. Math. (2016) 40:832-837].