LOMBOK PEARL QUALITY CLASSIFICATION USING A COMBINATION OF FEATURE EXTRACTION AND ARTIFICIAL NEURAL NETWORKS BASED ON SHAPE. pilar [Internet]. 13 September 2022 [dikutip 12 Februari 2026];18(2):167-72. Tersedia pada: https://ejournal.nusamandiri.ac.id/ejurnal/index.php/pilar/article/view/3507