Hasil Pencarian  ::  Simpan CSV :: Kembali

"Beginning with the Airline Deregulation Act of 1978 in US, followed by the European Union in 1997, airlines have been constructing route networks of their own choosing rather than operating ones implicitly chosen for them by civil aviation authority. These changes have had profound effects on many aspects of airline operation, particularly fares, service, quality, and safety. But, most importantly, airlines have altered their route structures by developing hub-and-spoke networks, and this has affected all of these aspects. This structure is likely to flourish around the world as a consequence of airline liberalization and the growing trend toward privatization of this industry.In a hub-and-spoke network, centrally located service facilities serve as the hubs. Flows from a set of outlying nonhub nodes arrive at hubs and, after regrouping, all leave the hub facilities bound either to other hubs or to their ultimate destinations. Thus, the flows from the same origin with different destinations are consolidated on the route to a hub facility and the flows with different origins but the same destination on the route out of a hub facility. The centralization and broader scope of operations let the system take advantage of economies of scale.This paper proposes a framework to optimize the flight network using hub-and-spoke system. This problem consists of the determination of hub number, hub location and route assignment in order to minimize the overall transportation cost. The model is solved using genetic algorithm approach. Two networking strategies are considered:1. Strict hubbing, in which a spoke is assigned to exactly one hub and all flows to/from spoke are channeled trough the same hub and 2. Nonstrict hubbing, in which a spoke can be assigned to more than one hub under certain condition. Different values of airport fixed costs are also implemented. Variations of these strategies are evaluated along with various parameters of air transport production using data on air passenger flows between top 30 Indonesian airports in 2000.The result shows that the adoption of hub-and-spoke network increase the overall system performance with increasing load factor, frequency, coverage area, revenue passenger kilometer, available seat kilometer and more efficient utilization of aircraft. Moreover, Nonstrict hubbing strategy offers smaller total system cost, more routes and more nonstop flights."

"Aktivitas logistik merupakan salah satu bagian dari rantai pasok supply chain yang sedang menjadi perhatian dibanyak negara, salah satunya Indonesia. Di Indonesia biaya logistik masih terhitung tinggi, dikarenakan adanya ketidakseimbangan aliran distribusi barang di Indonesia bagian Barat dengan bagian Timur. Saat ini pemerintah Indonesia sedang dalam proses untuk mempersiapkan pembangunan pelabuhan peti kemas strategis untuk menyeimbangkan permasalahan anatara Indonesia Timur dengan Indonesia Barat. Dilihat dari konsep perencanaan tersebut maka dalam penelitian tersebut akan mencari alternatif model matematika untuk mencari rute yang optimal dengan fungsi tujuan meminimumkan biaya. Dari model matematika tersebut didapatkan rute yang menghubungkan dari Indonesia bagian barat dengan Indonesia bagian timur.

---

Logistic is a part of supply chain that is being addressed in many countries, including Indonesia. The costly logistic of Indonesia is caused by imbalance trading between western and eastern regions in Indonesia. Challenging conditions come to the stakeholders particularly in the logistics sector. In this regard, the Government also plans to develop strategic container terminal ports. Concept of the planning in this research would also search for alternative a mathematics model to minimize logistics cost. From the model mathematics were obtained the route join the west Indonesia with eastern Indonesia."

"Tindakan pencegahan Covid 19 telah berdampak besar di banyak industri karena arus pelanggan yang tertekan yang biasanya mendukung bisnis. Covid-19 juga berdampak serius pada ekonomi global dan rantai pasokan global, termasuk pengiriman global. Letak geografis Indonesia yang diapit oleh dua samudera dan dua benua menjadikan wilayah laut Indonesia sebagai salah satu rute utama perdagangan dunia. Kondisi strategis Indonesia tidak diimbangi oleh rendahnya efisiensi logistik Indonesia. Makalah ini menghasilkan rekomendasi tentang rute logistik maritim Indonesia dan meningkatkannya untuk lebih mengeluarkan total biaya yang optimal. Perbaikan tersebut dicapai dengan menggunakan kombinasi rute yang belum dipertimbangkan dari penelitian sebelumnya. Masalahnya dimodelkan sebagai program bilangan bulat campuran dan Gurobi Optimization digunakan untuk menghasilkan solusi.

---

Covid 19 precautions have had a major impact in many industries due to the depressed flow of customers who usually support businesses. Covid-19 also seriously impacts the global economy and global supply chains, including global shipping. Indonesia's geographical location flanked by two oceans and two continents makes Indonesia's sea area one of the main routes of world trade. Indonesia's strategic conditions are not offset by Indonesia's low logistics efficiency. This paper produces recommendations on Indonesia's maritime logistics routes and improves them to further incur optimal total costs. Such improvements are achieved using a combination of routes that have not been considered from previsious research. The problem is modeled as a mixed-integer program and Gurobi Optimization is used to generate the solution."

"Industri otomotif merupakan salah satu sektor yang sedang berkembang pesat di Indonesia. Pertumbuhan ini memacu peningkatan pengiriman pasokan otomotif, tidak hanya di Pulau Jawa, tetapi juga di pulau-pulau lainnya. Peningkatan aktivitas distribusi ini, jika tidak disertai dengan perencanaan yang matang, dapat mengakibatkan kenaikan biaya distribusi yang signifikan. Oleh karena itu, diperlukan strategi distribusi yang optimal dari gudang hingga ke pelanggan. Penelitian ini mengembangkan model matematika untuk meminimalkan biaya distribusi menggunakan metode hub & spoke dengan pendekatan mixed integer linear programming (MILP). Model ini kemudian diterjemahkan ke dalam program Python menggunakan library PuLP. Biaya distribusi yang dianalisis terdiri dari biaya shuttle atau pengiriman first mile dan biaya truk atau pengiriman last mile. Hasil penelitian selama 26 periode menunjukkan bahwa model distribusi hub & spoke yang dikembangkan mampu mengurangi total biaya distribusi hingga 35% dibandingkan dengan biaya pengiriman aktual perusahaan. Selain itu, model ini juga menunjukkan tingkat utilisasi kendaraan yang optimal dengan rata-rata kapasitas muatan terisi 75% untuk shuttle dan 90% untuk truk pada setiap periode.

---

The automotive industry is one of the rapidly growing sectors in Indonesia. This growth has driven an increase in automotive supply shipments not only on the island of Java but also on other islands. Increased distribution activities, if not accompanied by thorough planning, can lead to a significant rise in distribution costs. Therefore, an optimal distribution strategy from the warehouse to the customer is essential. This study develops a mathematical model to minimize distribution costs using the hub & spoke method with a mixed integer linear programming (MILP) approach. The model is then translated into a Python program using the PuLP library. The distribution costs analyzed include shuttle costs or first mile delivery and truck costs or last mile delivery. The results of the study over 26 periods indicate that the proposed hub & spoke distribution model can reduce total distribution costs by up to 35% compared to the company's actual shipping costs. Additionally, this hub & spoke delivery model also shows optimal vehicle utilization rates with an average load capacity of 75% for shuttles and 90% for trucks in each period."

"Tol Laut adalah program pemerintah yang bertujuan menjadikan Indonesia sebagai poros maritim dunia, dengan cara meningkatkan kapasitas ekonomi nasional dan menurunkan disparitas ekonomi antar daerah. Mulai 2021 pembuatan jaringan berdasarkan hub and spoke mulai dilakukan oleh pemerintah dengan tujuan mengurangi biaya total dengan memanfaatkan economies of scale. Penelitian ini dilakukan untuk membuat design jaringan yang optimal dalam segi total biaya pengiriman dengan memanfaatkan genetika algoritma, pada penilitian ini terdapat dua kasus yang dinyatakan dalam bentuk model hub and spoke yaitu model tipe single allocation model dan model dengan hub tier satu dan hub tier dua. Pada kedua model tersebut dilakukan perhitungan dimana dipertimbangkan faktor diskon dengan yang tidak, kemudian perbandingan hasil biaya pelayaran dari kedua kasus tersebut dilakukan. Hasil penelitian ini memberikan desain jaringan dengan biaya pengiriman terminimum pada kedua kasus.

---

The Sea Highway is a government program that aims to make Indonesia the world's maritime axis, by increasing national economic capacity and reducing economic disparities between regions. Starting in 2021, the government will start making networks based on hub and spokes with the aim of reducing total costs by taking advantage of economies of scale. This research was conducted to create an optimal network design in terms of total shipping costs by utilizing genetic algorithms, in this study there are two cases expressed in the form of a hub and spoke model, namely the single allocation model and the model with tier one hub and tier two hub. In both models, a calculation is carried out with and without the discount factor, then the results of the shipping costs from the two cases are compared. The results of this study provide a network design with the minimum shipping cost for both cases."

"Global revenue by passenger kilometers over the last ten years has grown at an average of 4.7 percent per year. The high growth of air transport must be offset by equivalent airport investment: perhaps even a doubling of the percentage growth of numbers of passengers. The purpose of this paper is to build a development model for investment in hub-and-spoke airport networks. The methodology developed in this paper uses systems dynamics theory. The benefit of using this approach is that the variables in the model are determined through a systems thinking process; the determination of variables through such a thinking process considers causality between variables dynamically, logically, and realistically within a complex aviation industry system. The simulation model shows that using a system dynamics approach can be used to simulate airport infrastructure investment development in a hub-and-spoke network. One of the subsystems is congestion; the result of simulation of this subsystem yields the behavioral characteristics, which show that a surge in demand (which is then offset by the provision of capacity or capacity enlargement) will eventually become stable, indicated by a lack of lines on the runway side. This means that decreases in congestion will increase passenger demand, and will also enhance potential investment in airport infrastructure."

"Pemerintah Republik Indonesia telah mendorong penggunaan biodiesel B30 pada tahun 2020 dengan penetapan Peraturan Menteri Energi dan Sumber Daya Mineral Republik Indonesia No. 12 Tahun 2015. Hal ini berimplikasi pada peningkatan pengadopsian biodiesel di berbagai sektor. Untuk membentuk biodiesel B30, Fatty Acid Methyl Ester (FAME) digunakan sebagai bahan pencampur minyak solar dengan proporsi 30% untuk FAME dan 70% untuk minyak solar. Namun, perlu adanya perhatian lebih mengenai kendala yang dialami dalam proses distribusi FAME seperti jumlah titik serah yang turut meningkat seiring dengan volume pemanfaatan biodiesel yang meningkat dan banyaknya opsi pola pemenuhan kebutuhan FAME. Skema distribusi FAME yang dilakukan di Indonesia saat ini berbasis pada jaringan point-to-point atau pengiriman langsung dari titik suplai menuju ke titik serah. Dalam penelitian ini, penulis mencoba menggunakan jenis jaringan lain yaitu hub-and-spoke dengan menugaskan sejumlah titik suplai atau titik serah untuk menjadi sarana penerimaan, penyimpanan dan penyaluran FAME bagi daerah sekitarnya. Hasil dari optimasi yang dilakukan menunjukan bahwa terdapat trade off antara kedua tipe jaringan distribusi. Skenario point-to-point memiliki biaya distribusi 35% lebih rendah jika dibandingkan dengan skenario hub-and-spoke. Namun, skenario hub-and-spoke memiliki lead time 24% lebih rendah jika dibandingkan dengan skenario point-to-point

---

.The Government of the Republic of Indonesia has encouraged the use of B30 biodiesel in 2020 with the stipulation of Regulation of the Minister of Energy and Mineral Resources of the Republic of Indonesia No. 12 of 2015. This has implications for increasing biodiesel adoption in various sectors. To form biodiesel B30, Fatty Acid Methyl Ester (FAME) is used as a mixing material for diesel oil with a proportion of 30% for FAME and 70% for diesel oil. However, it is necessary to pay more attention to the constraints experienced in the FAME distribution process, such as the number of delivery points which also increases along with the increasing volume of biodiesel utilization and the many options for fulfilling FAME needs. The current FAME distribution scheme in Indonesia is based on a point-to-point network or direct delivery from the supply point to the delivery point. In this study, the researcher tries to use another type of network, namely hub-and-spoke by assigning several supply points or delivery points to be a means of receiving, storing, and distributing FAME for the surrounding area. The results of the optimization carried out show that there is a trade off between the two types of distribution networks. The point-to-point scenario has 35% lower distribution costs when compared to the hub-and-spoke scenario. However, the hub-and-spoke scenario has a 24% lower lead time when compared to the point-to-point scenario."

"This study addresses the hub network design problem considering demand uncertainty and hub congestion effects. The problem is formulated as a two-stage stochastic program with recourse model. The model provides a consistent set of hub locations, while adjusting network configuration in response to different demand realizations. A case study collected from real-world data was used to test the proposed model, and a sensitivity analysis was performed to know how several important parameters affected the solution"