The strategic selection of high-permeability ferrite cores represents a critical engineering decision that directly impacts transformer efficiency, size, and reliability in high-frequency applications. Oswell's systematic approach to core material optimization, combined with advanced manufacturing techniques, demonstrates that 20% loss reduction at 100kHz is achievable through careful balance of material properties and design parameters. As power electronics continue to evolve toward higher frequencies and greater power densities, these core selection strategies will remain essential for developing next-generation energy-efficient systems.