Browsing by Author "Guven, Ceyhun"

Now showing 1 - 3 of 3

Intelligent Container Repositioning with Depot Pricing Policies
(Springer Science and Business Media Deutschland GmbH, 2022) Ceyhun Güven; Erdinc Oner; Uǧur Eliiyi; Eliiyi, Ugur; Guven, Ceyhun; Oner, Erdinc; C. Kahraman , S. Cevik Onar , B. Oztaysi , I.U. Sari , A.C. Tolga , S. Cebi
Empty container management has always been a crucial issue in the logistics sector. Specifically the repositioning of empty containers plays an important role in the industry of maritime shipping. Not only has an economic impact on the stakeholders affiliated with the container logistics chains but also has an effect on the society in terms of environment and sustainability as the reduction in the movement of empty containers will also reduce fuel consumption. The main objective of this paper is to minimize the total cost. This total cost includes the cost required for transportation of the empty containers to their depots and the storage cost of these containers in the assigned depots. The types of costs involved in empty container repositioning are defined via the review of the related literature and industrial practices. In this study a mixed-integer linear programming model is developed that minimizes the total cost require in the repositioning of empty containers. The proposed model determines the storage depot of each empty container considering the depot pricing policies and distances between the port terminals and container depots. Computational results indicate that the proposed model can identify the best alternatives for empty container storage with minimum total cost. © 2022 Elsevier B.V. All rights reserved.
Citation - WoS: 21
Citation - Scopus: 27
Modelling and optimisation of online container stacking with operational constraints
(ROUTLEDGE JOURNALS TAYLOR & FRANCIS LTD, 2019) Ceyhun Guven; Deniz Tursel Eliiyi; Türsel Eliiyi, Deniz; Guven, Ceyhun; Eliiyi, Deniz Tursel
Container transportation plays a critical role in the global shipping network and container terminals need to improve their operations to increase efficiency. Storage yard of a container terminal is a temporary area where the containers stay until they are shipped to their next destination. We concentrate on increasing the efficiency of the storage yard by developing online stacking policies for each incoming container. An unproductive move of a container performed to reach another container stored underneath is called reshuffling. The objective in container stacking problem is to minimise the number of reshuffles thereby increasing the efficiency of terminal operations. Additional weight-related operational constraints bring additional complexity to the online stacking decisions. We propose a mathematical model for the optimal online assignment of an incoming export transit import or empty container. We also propose an optimal online stacking policy and compare it with a random policy through simulation. Additionally lower bounds for the performance measures are obtained through simulation by relaxing the operational constraints of the problem in a third stacking policy. We present and discuss the computational results in terms of four main performance measures.
Citation - WoS: 20
Citation - Scopus: 33
Trip allocation and stacking policies at a container terminal
(Elsevier, 2014) Ceyhun Güven; D. T. Eliiyi; Guven, Ceyhun; Eliiyi, Deniz Tursel
There are three crucial resources at container terminals, the yard cranes and the vehicles. The main objective of the terminal is the efficient use of these resources while performing different operations. The yard is a temporary storage area where containers remain until transported to their next location by truck train or vessel. Containers are stacked on top of each other in order to utilize the yard space efficiently. However stacking cranes can only directly access those containers at the top of the stack. As a result reshuffling/shifting occurs defined as an unproductive move of a container required to access another container stored underneath. We focus on increasing the efficiency of the yard via consideration of the container stacking optimization problem for transshipment inbound and outbound containers at a container terminal. The objective of the problem is to minimize container storage and retrieval times through avoidance of reshuffles resulting in more efficient loading/unloading operations and in turn minimizing the dwell time of containers. The main inputs are the type weight discharge port/location destined vessel/vehicle of the container and the expected departure time. Different stacking policies are proposed in this study and we also investigate the problem of allocating the transit container to outbound vessels to minimize dwell time at the terminal. Transit containers require multiple sea-trips to reach their final destination. Vessels departing from the terminal and destined for the same port may provide exchangeable trips for this type of container based on their several attributes and capacity restrictions. We consider this problem taking into account several factors that affect container/trip allocation decisions. The solution of this problem also has implications for the stacking problem. © 2016 Elsevier B.V. All rights reserved.