Convection with phase change during gas formation from methane hydrates via depressurization of porous layers -- Methane hydrates in porous layers: gas formation and convection -- Geometric optimization of periodic flow and heat transfer in a volume cooled by parallel tubes -- Thermodynamic optimization of geometry: T- and Y- shaped constructs of fluid streams -- Constructal design for cooling a disc-shaped area by conduction -- Optimization of fin tree geometry in a coaxial twostream.