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This paper investigates an optimal methodology for mitigating low-frequency oscillation concerns in power systems. The study explores the synergistic integration of a power system stabilizer (PSS) and a flexible alternating current transmission system (FACTS) to formulate an intelligent controller. A comprehensive analysis encompasses various PSS design strategies, including lead-lag (LL), proportional-derivative-integral (PID), and fractional-order proportional-integral-derivative (FOPID) controllers. The FACTS device selected for this investigation is a static VAR compensator (SVC), highlighting the exceptional efficacy of FOPID-based PSS over alternative strategies with a power oscillation damper. The study extends its scope to encompass a comparative assessment of two distinct optimization algorithms: the moth flame optimization (MFO) and the antlion optimization (ALO). The research is conducted using a single-machine infinite bus power system (SMIB) as the case study platform. A total of four diverse test scenarios are executed under varying operating conditions. The evaluation of the developed method employs six distinct performance indices to investigate the developed controller thoroughly. The outcomes reveal that the MFO-optimized FOPID-PSS and SVC controller outperforms other control schemes. This optimized configuration demonstrates substantial improvements across all performance indices. These findings underscore the superior capabilities of the proposed approach in enhancing power system stability and performance. [ABSTRACT FROM AUTHOR]

Small amount of large surface area graphene (G) is expected to significantly alter functional properties of polymers. The property enhancement is a function of degree of exfoliation and dispersion of G as well as its compatibility with base polymer. However, nonpolar nature of polyolefins such as polypropylene (PP) restricts homogeneous dispersion of G, leading to significant agglomeration and properties reduction. In this work, two compatibilizers, poly (ethylene‐co‐butyl acrylate) (EBA) (new compatibilizer) and PP‐grafted‐maleic anhydride (MA‐PP) (conventional compatibilizer) were compared to enhance the dispersion efficacy of G in PP. The EBA‐compatibilized nanocomposites exhibited 44% increase in the Young's modulus compared to 32% increment in MA‐PP‐compatibilized nanocomposites. Higher elongation at break for EBA‐compatibilized nanocomposites is attributed to lower degree of crystallinity in these nanocomposites. On the other hand, EBA‐compatibilized nanocomposites showed significantly improved thermal stability compared to MA‐PP‐compatibilized nanocomposites. The results indicate that EBA may act as a potential compatibilizer for G/PP nanocomposites. [ABSTRACT FROM AUTHOR]

An experimental investigation has been carried out on double cantilever beam specimens with different bond thicknesses to study the effect of bond thickness on lifetime of adhesive joints under mode I. This paper describes an approach to predict the rate of crack propagation. The approach is based on principles of linear elastic fracture mechanics and uses elevated temperature to accelerate the crack propagation under constant loads. The fracture energy of the joint is studied as a function of bond thickness. The results from short-term tests are analyzed and a simple model has been proposed to predict the variation of two kinetic parameters of the Paris law with bond thickness. [ABSTRACT FROM AUTHOR]