This paper presents a hybrid genetic algorithm with collective communication (HGACC) using distributed processing for the job shop scheduling problem. The genetic algorithm starts with a set of elite micro-populations created randomly, where the fitness of these individuals does not exceed a tuned upper bound in the makespan value. The computational processes distribute the micro-populations collectively. In the micro-populations, each individual's search for good solutions is directed toward the solution space of the fittest individual, identified by an approximation of genetic traits. In each generation of the genetic algorithm, the best individual from each micro-population migrates to another micro-population to maintain diversity in populations. Changes in the genetic sequence are applied to each individual by the simulated annealing algorithm (iterative mutation). In this paper, the results obtained show that the genetic algorithm achieves excellent results, as compared to other genetic algorithms. It is also better than other non-genetic meta heuristics or competes with them.

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This study reports for the first time the isolation, identification and characterization of lipase-producing thermophilic strain from the geothermal water of the El Chichón volcano crater lake. Two strains were identified by 16S rRNA sequencing as Geobacillus jurassicus CHI2 and Geobacillus stearothermophilus CHI1. Results showed that G. jurassicus CHI2 is Gram-positive, able to ferment maltose, fructose and sucrose and to hydrolyze starch and casein; while G. stearothermophilus CHI1 showed to be Gram-variable, able to ferment maltose and fructose and to hydrolyze starch. Colonies of both strains presented irregular shape, umbilicated elevation of gummy texture and cells presented flagellar movement to survive in fluids with high temperature and mass gradients due to complex phenomena of heat and mass transfer present in the geothermal fluids. Lipase production for G. stearothermophilus CHI1 was also evaluated. It was found that this strain possesses a growth associated with extracellular lipase production with a high activity of 143 U/mL at 8.3 h of incubation time, superior to the activities reported for other microorganisms of genus Geobacillus; for this reason, it can be said that the thermal flow of the El Chichón volcano crater lake can be a useful source of lipase-producing thermophilic bacteria.

Heat exchangers play an important role in different industrial processes; therefore, it is important to characterize these devices to improve their efficiency by guaranteeing the efficient use of energy. In this study, we carry out a numerical analysis of flow dynamics, heat transfer, and entropy generation inside a heat exchanger; an aqueous medium used for oil extraction flows through the exchanger. Hot water flows on the shell side; nanoparticles have been added to the water in order to improve heat transfer toward the cold aqueous medium flowing on the tube side. The aqueous medium must reach a certain temperature in order to obtain its oil extraction properties. The analysis is performed for different Richardson numbers (Ri = 0.1–10), nanofluid volume fractions (φ = 0.00–0.06), and heat exchanger heights (H = 0.6–1.0). Results are presented in terms of Nusselt number, total entropy generation, Bejan number, and performance evaluation criterion. Results showed that heat exchanger performance increases with the increase in Ri when Ri > 1 and when reducing H.