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.

T-spherical fuzzy power aggregation operators and their applications in multi-attribute decision making

Abstract: The paper aims to present the concept of power aggregation operators for the T-spherical fuzzy sets (T-SFSs). T-SFS is a powerful concept, with four membership functions denoting membership, abstinence, non-membership and refusal degree, to deal with the uncertain information as compared to other existing fuzzy sets. On the other hand, the relationship between the different pairs of the attributes are well recorded in terms of power operators. Thus, keeping these advantages of T-SFSs and power operator, the objective of this work is to define several weighted averaging and geometric power aggregation operators. The stated operators named as T-spherical fuzzy weighted, ordered weighted, hybrid averaging and geometric operators for the collection of the T-SFSs. The various properties and the special cases of them are also derived. Further, the consequences of proposed new power aggregation operators are studied in view of some constraints. Finally, a multiple attribute decision making algorithm, based on the proposed operators, is established to solve the problems with uncertain information and illustrate with numerical examples. A comparative study, superiority analysis and discussion of the proposed approach are furnished to confirm the approach.

Steady-state creep behavior in an isotropic functionally graded material rotating disc of Al-SiC composite

Abstract: Steady-state creep response in a particle-reinforced isotropic functionally graded material (FGM) disc with linear variation of particle distribution along the radial distance has been investigated and compared with that of a disc containing the same amount of particle distributed uniformly. In view of the application of rotating discs in friction drives, turbines, and a number of other machine components, which are often exposed to elevated temperatures, weight saving without impairing the creep response may be a desirable goal. The disc under investigation is made of a composite containing silicon carbide particles in a matrix of 6061 aluminum alloy, and the steady-state creep response of the composite is described by Norton’s law. The material parameters of creep vary along the radial distance in the disc due to varying composition, and this variation has been estimated by regression fit of the available experimental data. The present analysis indicates that the tangetial stress increases due to increased density caused by a higher particle content in the region near the inner radius of the FGM disc. But it is more than compensated by the lowering of creep parameters due to increased particle content, and consequently, the steady-state creep rate decreases compared to those estimated in a disc with the same average particle content distributed uniformly. In the region near the outer radius, the tangential stress decreases and the creep parameters increase, both due to relatively lower particle content. But the resulting lower tangential stress is able to decrease the creep rate in this region overcoming the effect of increased creep parameters. Thus, for the assumed linear particle distributions in an isotropic rotating disc, the steady-state tangential and radial creep rates are smaller by almost an order of magnitude compared to those in an isotropic disc with uniform particle distribution.