2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/128837We investigate a method of construction of Calabi--Yau manifolds, that is, by smoothing normal crossing varieties. We develop some theories for calculating the Picard groups of the Calabi--Yau manifolds obtained in this method. Some applications are included, such as construction of new examples of Calabi--Yau 3-folds with Picard number one with some interesting properties.A large revision was made. Basically the paper returned to its previous version (v.2). The Kaehlerness arguement in Propositon 9.1 of v.3 needs correctionAlgebraic GeometryDifferential Geometry14J32; 14H10text