Judul: Genetic Algorithm on Solving Travelling Salesman Problems for Distribution of Organic Porridge Products
Abstrak: Pada penelitian ini, dibahas pencarian rute terpendek untuk mendistribusikan produk bubur organik yang diproduksi oleh PT. Rofindiya Ekamulia Sukses ke sejumlah outlet, yang mana setiap outlet hanya dapat dikunjungi satu kali saja dan proses distribusi dimulai dan diakhiri dari suatu outlet yang sama. Terdapat 44 outlet yang pada awalnya terbagi ke dalam 9 jalur distribusi, yang kemudian penulis usulkan dikelompokkan menjadi 3 jalur distribusi saja untuk efisiensi perusahaan. Permasalahan pendistribusian produk tersebut pada masing-masing jalur distribusi dapat dikategorikan sebagai travelling salesman problems (TSP). Pencarian rute terpendek pada masing-masing jalur distribusi dilakukan dengan menggunakan algoritme genetika (GA). Dalam implementasi GA, barisan outlet pada suatu jalur distribusi direpresentasikan sebagai barisan gen pada suatu kromosom. Nilai fitness pada GA dalam hal ini diasosiasikan sebagai total jarak tempuh suatu rute, sehingga implementasi GA dalam penelitian ini diarahkan untuk memperoleh nilai fitness yang terkecil. Hasil implementasi GA menunjukkan adanya perbaikan total jarak tempuh bila jumlah iterasi dan ukuran populasi ditingkatkan. Implementasi GA dilakukan dengan menggunakan bahasa pemrograman Octave., This study discussed finding a shortest route to distribute the organic porridge products produced by PT. Rofindiya Ekamulia Sukses to some outlets, in which each outlet is visited exactly once and the distribution process is started and ended from the same outlet. There are 44 outlets involved in this study. The outlets are initially grouped into 9 distribution tracks. The authors proposed to regroup them into 3 distribution tracks to increase distribution efficiency. The distribution problem on each track can be categorized as a travelling salesman problems (TSP). Each of those 3 distribution problems is solved using genetic algorithm (GA). In the implementation of GA, the outlet sequence on a distribution route is represented as a gene sequence on a chromosome. Since the fitness value of a chromosome is associated with total travelling distance of that route, the implementation of GA in this study is directed to obtain a smallest fitness value. The GA implementation shows that the total travelling distance can be reduced, up to a certain level, by increasing the number of iterations and the population size. The GA implementation is done using the programming language Octave.
Keyword: GA, route, total distance, TSP

Judul: The Application of Genetic Algorithm in Vehicle Routing Problem and Its Implementation on Rastra Distribution
Abstrak: Rute pendistribusian kendaraan terkait proses distribusi produk merupakan masalah yang dihadapi produsen dalam memenuhi kebutuhan konsumen. Penentuan rute distribusi kendaraan atau vehicle routing problem (VRP) bertujuan menentukan rute dan penggunaan kendaraan agar biaya yang dikeluarkan minimal. Pada penelitian ini akan dibahas rute pendistribusian kendaraan untuk mengantarkan beras sejahtera dari beberapa gudang penyimpanan ke desa/kelurahan tertentu yang dimiliki Perum Bulog kabupaten Ponorogo untuk satu dari dua belas periode. Salah satu desa/kelurahan memiliki permintaan yang melebihi kapasitas kendaraan, sehingga lokasi tersebut dapat dikunjungi kendaraan dengan pendistribusian terpisah. VRP dapat diselesaikan menggunakan metode eksak dan metode heuristik. Metode heuristik genetic algorithm dengan pencarian solusi awal melalui nearest neighbour diterapkan untuk masalah pendistribusian beras pada periode di Perum Bulog. Solusi yang dihasilkan oleh metode heuristik memiliki waktu yang lebih cepat dibandingkan solusi metode eksak., The vehicle distribution route related to the product distribution process is a problem faced by manufacturers in meeting consumer needs. Determination of vehicle distribution routes or vehicle routing problem (VRP) aims to determine the route and use of vehicles so that the costs incurred are minimal. In this study the route of distribution of vehicles to deliver prosperous rice from several storage warehouses to certain villages will be discussed, which is owned by Perum Bulog in Ponorogo Regency for one of the twelve periods. One of the village has a demand that exceeds the vehicle capacity, so that the location can be visited by vehicles with split delivery. VRP can be solved using exact methods and heuristic methods. The heuristic genetic algorithm method by searching for an initial solution through the nearest neighbour is applied to the problem of distributing rice during the period at Perum Bulog. The solution produced by the heuristic methods has a faster time than the solution of the exact methods.
Keyword: distribution, heuristic method, multidepot, split delivery, vehicle routing problem

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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