Abstract We study two $$\mathcal {NP}$$ NP -hard single-machine scheduling problems with generalized due-dates. In such problems, due-dates are associated positions in the job sequence rather than jobs. Accordingly, that is assigned to position j processing order (job sequence), a predefined due-date, $$\delt...

abstract the present study was aimed to investigate the planting dates effects on yield associated traits and also determining stability of the result of factor analysis and stepwise regression analysis in different planting dates of rapeseed genotypes at biekol agriculture research station during 2011-12 cropping season. result of split plot analysis exhibited significant genotypes effects for...