PENERAPAN METODE MIXED INTEGER LINIER PROGRAMMING (MILP) GUNA MEMINIMALKAN BIAYA DISTRIBUSI PUPUK NPK

Abstract

ABSTRAK CV. XYZ merupakan produsen yang berfokus pada pembuatan Pupuk NPK varian 13-6-27. Dalam sector logistic perusahaan kerap terhambat oleh penjadwalan armada yang kurang efisien, adanya rute yang bolak-balik, utilisasi muatan kendaraan yang belum maksimal, serta kendala batas waktu pengiriman (time windows) ke konsumen. Guna menyelesaikan kompleksitas tersebut dengan menggunakan permodelan Capacited Vehicle Routing Problem With Time Windows (CVRPTW) untuk penyelesaiannya menggunakan Mixed Integer Linier Programming (MILP). Serangkaian variable yang dianaisis meliputi koordinat pelanggan, rentang jarak, durasi perjalanan, kapasitas armada, kuantitas permintaan, komponen biaya rill, hingga tenggat pelayanan customer. Berdasarkan hasil komputasi model usulan, terjadi efisiensi signifikan berupa reduksi akumulasi jarak distribusi dari 2.053 km menjadi 1.272 km, sedangkan durasi tempuh dari 2.298 menit menjadi 1.440 menit, serta penghematan biaya distribusi dari Rp. 6.575.700 menjadi Rp. 4.189.300. Hasil dari diatas menunjukkan bahwa pendekatan MILP mampu mentranformasi system logistic pada CV. XYZ menjadi jauh lebih optimal dan efisien. ABSTRACT CV. XYZ is a manufacturer specializing in the production of NPK 13-6-27 fertilizer. Within the company's logistics sector, distribution operations are frequently hindered by inefficient fleet scheduling, repetitive back-and-forth routing, underutilized vehicle capacities, and strict delivery time windows for customers. To address these complexities, this study integrates the Capacitated Vehicle Routing Problem with Time Windows (CVRPTW) model, solved using Mixed-Integer Linear Programming (MILP). A comprehensive set of variables was analyzed, including customer coordinates, travel distances, transit durations, fleet capacities, demand quantities, real cost components, and service time constraints for each client. Based on the computational results of the proposed model, a significant efficiency was achieved: the cumulative distribution distance was reduced from 2,053 km to 1,272 km , travel duration decreased from 2,298 minutes to 1,440 minutes , and total distribution costs were minimized from IDR 6,575,700 to IDR 4,189,300. These findings demonstrate that the MILP approach successfully transforms the logistics system at CV. XYZ into a highly optimal and efficient operation.