Judul: Optimasi Hetereogeneous Fleet Vehicle Routing Problem with Time Windows pada Distribusi Produk Beku dengan Algoritma Genetika
Abstrak: Penentuan rute distribusi yang disebut sebagai vehicle routing problem (VRP) merupakan salah satu permasalahan dalam sistem distribusi. PT X merupakan perusahaan importir yang menyediakan berbagai produk beku seperti daging sapi, daging ayam, daging kerbau, hasil laut, kentang,dan lain-lain. Proses penentuan rute distribusi di PT X dilakukan berdasarkan jumlah permintaan yang tidak tetap untuk setiap harinya yang menyebabkan kapasitas kendaraan tidak terutilisasi secara maksimal sesuai dengan standar perusahaan yang harus dipenuhi minimal 80%. Penentuan rute distribusi dilakukan menggunakan perangkat lunak Locus yang seringkali ditemukan beberapa rute yang tidak sesuai titik dan rute yang tersedia lebih jauh mengakibatkan tidak terpenuhinya time windows sehingga terjadi keterlambatan. Oleh karena itu, diperlukan pengkajian ulang efisiensi sistem distribusi yang sudah ada. Penelitian ini bertujuan meminumumkan jarak distribusi dengan melakukan pencarian rute distribusi terpendek. Metode penelitian ini diantaranya adalah pengumpulan alamat konsumen sebagai data utama dan pengolahan data. Proses optimasi perncarian rute dilakukan menggunakan algoritma genetika. Berdasarkan hasil optimasi diperoleh pengurangan total jarak tempuh sebesar 149.1 km dan penurunan penggunaan jumlah kendaraan sebanyak 2 unit. Selain itu, terjadi peningkatan rata-rata utilitas kendaraan sebesar 2.64%. Melalui hasil tersebut metode Algoritma Genetika yang digunakan mampu menghasilkan rute distribusi yang lebih optimal.
Keyword: Distribution, Genetic Algorithm, Time Windows, Vehicle Routing Problem

Judul: Penyelesaian Vehicle Routing Problem pada Pendistribusian Sayuran Dataran Tinggi Menggunakan Algoritme Genetika (Studi Kasus PT Saung Mirwan)
Abstrak: Vehicle routing problem (VRP) is an important issue on a transportation system that aims at minimizing the total vehicle mileage to reduce vehicle operating cost to a minimum. Vehicle routing problem belongs to the class of non-polynomial hard (NP-hard), which generally uses a heuristic approach to find a solution. In this time, Vehicle routing problem resolution will be applied to the distribution of highland vegetables from PT. Saung Mirwan as the vegetable distribution center. The problems that often arise in the distribution of highland plain vegetables is to how minimize the total of transportation costs without sacrificing the goal completion time to reduce the risk of the decline in the quality of vegetables during the trip. Issues will become increasingly complex if the vehicle routing problem is flexible to changes that occur in the limit or the value of decision variables. The problems encountered in this case include heterogeneous multi fleet VRP, single source, single trip, and multi-product. Therefore, this research used genetic algorithm optimization method (GA) to solve the problem. Genetic algorithm is one of the heuristic methods, which is analogous to the process of evolution by natural selection phase, crossover and mutation. In this paper a simulation is performed by searching the optimum solution to the location of the distribution as the destination points. Optimum solutions are obtained in the form of division of highland vegetable distribution channels that meet the existing constraints. As a solution, there was reduction of the distribution time of about 1 hour 58 minutes or an increase in time efficiency by approximately 32.22% and a reduction of the fleet utilization by 1 fleet or an increase of fleet efficiency by 14.28%.
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Judul: Hydroxyapatite-Chitosan Composite Coating on Stainless Steel 316 to Improve Corrosion Resistance
Abstrak: Metals that were used in bone implantation should have good corrosion resistance that were not easily corroded when implanted into the body. Metal corrosion resistance of stainless steel 316 can be enhanced through the metal coating by hydroxyapatite-chitosan composite with composition ratio of hydroxyapatite (gram) and chitosan 3% (mL) 0.2:0, 0.2:0.1, 0.2:0.5, 0.2:1.0, and 0.2:1.5. Besides improving the corrosion resistance of metal, the presence of chitosan also maintain the position of hydroxyapatite on metal surfaces. Corrosion resistance increases with increasing amount of chitosan added and the best composition of hydroxyapatite-chitosan composite was 0.2:1.0.
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