Permutation flow-shop scheduling is the strategy that ensures the processing of jobs on each subsequent machine in the exact same order while optimizing an objective, which generally is the minimization of makespan. Because of its NP-Complete nature, a substantial portion of the literature has mainly focused on computational efficiency and the development of different AI-based hybrid techniques. Particle Swarm Optimization (PSO) has also been frequently used for this purpose in the recent past. Following the trend and to further explore the optimizing capabilities of PSO, first, a standard PSO was developed during this research, then the same PSO was hybridized with Variable Neighborhood Search (PSO-VNS) and later on with Simulated Annealing (PSO-VNS-SA) to handle Permutation Flow-Shop Scheduling Problems (PFSP). The effect of hybridization was validated through an internal comparison based on the results of 120 different instances devised by Taillard with variable problem sizes. Moreover, further comparison with other reported hybrid metaheuristics has proved that the hybrid PSO (HPSO) developed during this research performed exceedingly well. A smaller value of 0.48 of ARPD (Average Relative Performance Difference) for the algorithm is evidence of its robust nature and significantly improved performance in optimizing the makespan as compared to other algorithms.

An experimental investigation of static and fatigue strength of double strap joints, using thermosetting and thermoplastic adhesives, between aluminum alloy 6061-T6 and carbon fiber metal laminate (CFML) has been carried out during this research. The static properties of joints, using thermosetting adhesives, were also determined while varying the temperature values. Two types of specimens were prepared: one, using YD-128 epoxy and the other using thermoplastic polyurethane by applying hand layup method. Results of both tensile and fatigue testing indicated better strength for thermosetting double strap joint both in elongation and fatigue cycles. For experimental validation of joints, finite element modeling has also been used during this research. Furthermore, the thermosetting double strap joint with maximum shear strength has been tested under a series of high temperatures. Temperature dependence of thermosetting epoxy adhesive indicated an increase in tensile strength of joint below the service temperature. However, a 50% drop in joint's shear strength was observed when temperature was raised from 25°C to 60°C. Similarly, an increase in tensile strength of about 8.11% was observed at temperatures between ¹20°C to 25°C. The mode of failure for all combinations of thermosetting joints is mixed mode and cohesive failure whereas adhesive failure was observed for thermoplastics joints.