Fractional Factorial Designs with Alias and Trend-Free Analysis // Constructs mixed-level and regular fractional factorial designs using coordinate-exchange optimization and automatic generator search. Design quality is evaluated with J2 and balance (H-hat) criteria, alias structures are computed via correlation-based chaining, and deterministic trend-free run orders can be produced following Coster (1993) doi:10.1214/aos/1176349410. Mixed-level design construction follows the NONBPA approach of Pantoja-Pacheco et al. (2021) doi:10.3390/math9131455. Regular fraction identification follows Guo, Simpson and Pignatiello (2007) doi:10.1080/00224065.2007.11917691. Alias structure computation follows Rios-Lira et al.(2021) doi:10.3390/math9233053.