Two-echelon freight transport optimisation: unifying concepts via a systematic review

Multi-echelon distribution schemes are one of the most common strategies adopted by the transport companies in an aim of cost reduction, but their identification in scientific literature is not always easy due to a lack of unification. This paper presents the main concepts of two-echelon distribution via a systematic review, in the specific a meta-narrative analysis, in order to identify and unify the main concepts, issues and methods that can be helpful for scientists and transport practitioners. The problem of system cost optimisation in two-echelon freight transport systems is defined. Moreover, the main variants are synthetically presented and discussed. Finally, future research directions are proposed.location-routing problems, multi-echelon distribution, cross-docking, combinatorial optimisation, systematic review.

Two-echelon freight transport optimisation: unifying concepts via a systematic review

Multi-echelon distribution schemes are one of the most common strategies adopted by the transport companies in an aim of cost reduction, but their identification in scientific literature is not always easy due to a lack of unification. This paper presents the main concepts of two-echelon distribution via a systematic review, in the specific a meta-narrative analysis, in order to identify and unify the main concepts, issues and methods that can be helpful for scientists and transport practitioners. The problem of system cost optimisation in two-echelon freight transport systems is defined. Moreover, the main variants are synthetically presented and discussed. Finally, future research directions are proposed

RELOKASI SPPBE SEBAGAI GUDANG ANTARA DAN OPTIMISASI RUTE KENDARAAN UNTUK MENURUNKAN BIAYA DISTRIBUSI GAS LPG 3 KG DI KOTA BANDUNG (STUDI KASUS : PT PERTAMINA WILAYAH PEMASARAN KOTA BANDUNG TIMUR)

PT. Pertamina merupakan perusahaan milik negara yang bergerak dibidang energi, salah satu produknya adalah gas minyak bumi yang dicairkan atau biasa disebut lpg. Dalam pendistribusian gas lpg 3kg di kota Bandung, PT. Pertamina memiliki 6 SPPBE yang melayani 72 agen. Sistem distribusi yang dianut perusahaan saat ini adalah sistem distribusi terbuka yang artinya SPPBE dapat melayani agen mana saja, atau dengan kata lain SPPBE tidak memiliki agen tetap yang harus dilayaninya. Ke-6 SPPBE yang berada di kota Bandung ini berlokasi disatu wilayah yaitu Bandung Timur, hal ini menyebabkan jarak tempuh kendaraan menjadi besar. Disisi lain, SPPBE dalam melakukan kegiatan distribusi menggunakan satu kendaraan untuk setiap agen yang dilayaninya atau dengan kata lain muatan dalam kendaraan tidak dimaksimalkan. Lokasi SPPBE yang berjauhan dengan lokasi agen ini mengakibatkan besarnya jarak tempuh kendaraan serta kapasitas kendaraan yang tidak dimaksimalkan akan mengakibatkan tingginya biaya transportasi dan biaya distribusi yang harus dikeluarkan oleh perusahaan. Oleh karena itu, dalam penelitian ini diusulkan rancangan pemecahan masalah yang dapat menyelesaikan permasalahan yang dihadapi perusahaan. Dalam penelitian ini diusulkan 6 kelompok agen dengan pendekatan Fuzzy C-Means agar SPPBE memiliki kelompok layanan yang tetap. Relokasi SPPBE juga dilakukan dengan pendekatan P-Median Greedy Dropping Heuristic Algorithm sehingga dalam setiap kelompok memiliki SPPBE untuk mengalokasikan kebutuhan dalam kelompok layanannya. Dari relokasi SPPBE dilakukan penentuan rute terpendek yang dilalui kendaraan dengan menggunakan pendekatan Insertion Heuristic, yang kemudian rute tersebut dioptimisasi dengan pendekatan Tabu Search. Dari hasil perhitungan, hasil dari Tabu Search memberikan hasil yang lebih baik yaitu total jarak 350,4 km dengan total biaya dsitribusi Rp. 11.604.954,33 perhari yang harus dikeluarkan perusahaan, sedangkan pada kondisi eksisting sebesar Rp. 39.184.998, sehingga penghematannya adalah sebesar 70,38% dari biaya distribusi pada kondisi eksisting. Kata Kunci : Fuzzy C-Means, P-Median, Greedy Gropping Heuristic, Insertion Heuristic, Tabu Search Algorithm, Minimasi Biaya Distribusi

Multi-echelon distribution systems in city logistics

In the last decades , the increasing quality of services requested by the cust omer, yields to the necessity of optimizing the whole distribution process. This goal may be achieved through a smart exploitation of existing resources other than a clever planning of the whole distribution process. For doing that, it is necessary to enha nce goods consolidation. One of the most efficient way to implement it is to adopt Multi - Echelon distribution systems which are very common in City Logistic context, in which they allow to keep large trucks from the city center, with strong environmental a dvantages . The aim of the paper is to review routing problems arising in City Logistics , in which multi - e chelon distribution systems are involved: the Two Echelon Location Routing Problem ( 2E - LRP) , the Two Echelon Vehicle Routing Problem (2E - VRP) and Truck and Trailer Routing Problem (TTRP), and to discuss literature on optimization methods, both exact and heuristic, developed to address these problems

Last-mile delivery in favelas: an explanatory study with Brazilian Companies

In urban logistics, the last-mile delivery from warehouse to the consumer's home has become more and more challenging with the continuous growth of urbanization, particularly in developing countries when addressing the logistical difficulties of distributing products in low-income population. This work presents an approach how companies distribute products within brazilian Favelas. Delivering products in these scenarios are not an easy task, high concentration of households without formal urbanization imposes hurdles to find and access to specific location added to the high number of cargo stolen, leads to lot of obstacles in this last mile operations. The company’s strategies are found by matching product type with Favela type in quadrants in the Conditions Decision Matrix. The results showed an emergent proposed model from data based on theory that helps to understand the last-mile delivery in Favelas having the risk as the moderator factor of logistics performance. The paper highlights that companies do not change information, practices neither synergies between their distribution models as well as do not relate to communities in, for example, social actions, in the vast majority of cases. It concludes by mapping the practical strategies applicable for the companies in the last-mil

The Two-Echelon Multi-products Location-Routing problem with Pickup and Delivery: Formulation and heuristic approaches

The two-echelon location routing problem (LRP-2E) considers the first-level routes that serve from one depot a set of processing centers, which must be located and the second-level routes that serve customers from the open processing centers. In this paper, we consider an extension of the LRP-2E, where the second level routes include three constraints, that have not been considered simultaneously in the location routing literature, namely, multi-product, pickup and delivery and the use of the processing center as intermediate facility in the second-level routes. This new variant is named two-Echelon Multi-products Location-Routing problem with Pickup and Delivery (LRP-MPPD-2E). The objective of LRP-MPPD-2E is to minimize both the location and the routing costs, considering the new constraints. The first echelon deals with the selection of processing centers from a set of potential sites simultaneously with the construction of the first-level routes, such that each route starting from the main depot, visits the selected processing centers and returns to the main depot. The second echelon aims at assigning customers to the selected processing centers and defining the second-level routes. Each second-level route, starts at a processing center, visits a set of customers, through one or several processing centers, and then returns to the first processing center. We present a mixed integer linear model for the problem and use a Cplex solver to solve small-scale instances. Furthermore, we propose non-trivial extensions of nearest neighbour and insertion approaches. We also develop clustering based approaches that seldom investigated on location routing. Computational experiments are conducted to evaluate and to compare the performances of proposed approaches. The results confirm the effectiveness of clustering approaches.