Liner Shipping Route Research Articles

Designing robust liner shipping schedules: Optimizing recovery actions and buffer times

It is important for liner shipping companies to maintain cost efficient and robust liner shipping networks. Regularly, they set up pro-forma schedules, yet it is difficult to stay on time. We consider the problem of managing the delays. Therefore, we need to determine an optimal recovery policy and buffer time allocation to the ship route in order to minimize the total costs associated with delays and recovery actions, such as increasing sailing speed. We introduce a general framework consisting of a mixed integer programming formulation to solve discrete stochastic decision problems with short and long term decisions and apply this framework to the above described problem. Furthermore, we propose and test four heuristics for this problem. We compared the results of our method with an existing liner shipping route schedule and found a cost decrease of 28.9% after optimizing the buffer time distribution compared to the cost of sailing the current route schedule at constant speed.

A comprehensive multi-objective optimization model for the vessel scheduling problem in liner shipping

The international seaborne trade volumes have been continuously increasing over the last years. Many liner shipping companies started consolidation to form stronger alliances and attract new customers. In order to remain competitive and avoid potential monetary losses, liner shipping companies have to improve efficiency of their vessel schedules. Some of the decisions that have to be made by liner shipping companies are conflicting in their nature. However, the existing vessel scheduling models generally combine the conflicting objectives into one objective function, which aims to minimize the total route service cost. Such approach imposes limitations for liner shipping companies in the analysis of tradeoffs between the conflicting objectives. To avoid the latter drawback, this study proposes a multi-objective mixed integer nonlinear optimization model for the vessel scheduling problem, which accounts for all major route service cost components reported in the literature and separates them in two conflicting groups. The original mixed integer nonlinear model is linearized by discretizing the vessel sailing speed reciprocal, and the Global Multi-Objective Optimization Algorithm is developed to solve the linearized model. A set of numerical experiments are conducted for the Asia-Mediterranean Express Service liner shipping route. Results demonstrate that negotiation of both vessel service time windows and handling rates between liner shipping companies and marine container terminal operators may significantly reduce the total route service cost components. Furthermore, vessel schedules are found to be more sensitive to the unit fuel cost as compared to the unit carbon dioxide emission cost.

Green vessel scheduling in liner shipping: Modeling carbon dioxide emission costs in sea and at ports of call

Abstract Considering a substantial increase in volumes of the international seaborne trade and drastic climate changes due to carbon dioxide emissions, liner shipping companies have to improve planning of their vessel schedules and improve energy efficiency. This paper presents a novel mixed integer non-linear mathematical model for the green vessel scheduling problem, which directly accounts for the carbon dioxide emission costs in sea and at ports of call. The original non-linear model is linearized and then solved using CPLEX. A set of numerical experiments are conducted for a real-life liner shipping route to reveal managerial insights that can be of importance to liner shipping companies. Results indicate that the proposed mathematical model can serve as an efficient planning tool for liner shipping companies and may assist with evaluation of various carbon dioxide taxation schemes. Increasing carbon dioxide tax may substantially change the design of vessel schedules, incur additional route service costs, and improve the environmental sustainability. However, the effects from increasing carbon dioxide tax on the marine container terminal operations are found to be very limited.

Contestability of Container Liner Shipping Market in Alliance Era

ABSTRACT A cross section panel model is applied to estimate the effect that the Herfindahl-Hirschman Index (HHI) has on container freight rates for a sample of six major container liner shipping routes during 2009 to 2011. The estimated coefficient of HHI is non-positive and statistically insignificant, indicating that higher concentration level does not lead to high price and the container liner shipping market is contestable for the period under consideration. The suggestion that efficiency can be achieved without actual competition in a contestable market is highly significant for policy makers.

The green vessel scheduling problem with transit time requirements in a liner shipping route with Emission Control Areas

Increasing volumes of the international seaborne trade and new regulations on vessel emissions require liner shipping companies to enhance efficiency of their operations to remain competitive and in the meantime comply with the established restrictions on emissions that are produced by vessels. This paper presents a novel mixed integer nonlinear mathematical programming model for the green vessel scheduling problem with transit time requirements in a liner shipping route with “Emission Control Areas”, which not only enforces constraints on the quantity of emissions that are produced by vessels within “Emission Control Areas”, but also captures the cargo transit time requirements. The model’s objective aims to minimize the overall route service cost. A number of linearization techniques are proposed for linearizing the original nonlinear problem. The dynamic secant approximation procedure is used to solve the linearized problem. A set of numerical experiments are performed to evaluate the efficiency of the proposed solution approach and assess the effect of introducing both emission constraints and cargo transit time requirements on design of vessel schedules.

Multi-objective optimization for a liner shipping service from different perspectives

Abstract This paper considers the optimization problem for the ship deployment, the planned sailing speed, and the service scheduling in a liner shipping route with both sea and port uncertainties taking multiple objectives from different perspectives. The main purposes are three-folds: first, defining key performance indicators (KPI) in liner shipping service design problem from different stakeholders’ perspectives; second, investigating the relationships between the identified KPIs and their impact on the optimal solutions; third, evaluating the impact of different speed strategies on the KPIs and the optimal solutions.

Vessel scheduling in liner shipping: Modeling transport of perishable assets

International seaborne containerized trade significantly increased over the last years. Some assets transported in a containerized form by vessels are perishable in nature. Perishable assets deteriorate due to certain operational and environmental factors. This paper proposes a novel mixed integer non-linear mathematical model for the vessel scheduling problem in a liner shipping route with perishable assets, which explicitly captures decay of perishable assets on board the vessels. The objective aims to minimize the total route service cost, including the asset decay cost. The original non-linear mathematical model is linearized using a set of piecewise linear secant approximations. CPLEX is used to solve the linearized mathematical model. Numerical experiments are conducted for the French Asia Line 1 route, served by CMA CGM liner shipping company, to evaluate performance of the suggested solution approach and reveal some important managerial insights. Results demonstrate that the developed mathematical model can serve as an effective planning tool for liner shipping companies in designing efficient vessel schedules and reducing decay of perishable assets on board the vessels.

The Vessel Scheduling Problem in a Liner Shipping Route with Heterogeneous Fleet

Increasing volumes of the international seaborne trade force liner shipping companies to improve efficiency of their operations to remain competitive. Many of liner shipping companies continue increasing size of their vessels, as larger vessels provide lower voyage costs per container due to their economies of scale. Larger vessels also allow liner shipping companies more efficiently share the demand with the alliance partners. Nowadays, many of liner shipping routes are served by vessels of different types (e.g., small, medium, large). However, the key assumption of studies on vessel scheduling, conducted to date, is homogeneous nature of the vessel fleet (i.e., all vessels in the fleet, serving a given liner shipping route, have the same technical characteristics). This study proposes a novel mathematical model for the vessel scheduling problem with heterogeneous fleet. The objective of a mixed integer non-linear model is to minimize the total vessel turnaround cost. Due to high non-linearity of the proposed mathematical model a non-linear optimization solver is used to solve it. Numerical experiments are performed to evaluate efficiency of the proposed solution approach and the novel methodology. Results demonstrate a computational efficiency of the adopted solution approach. Furthermore, vessel schedules are found to be more sensitive to introduction of larger vessels in the fleet as compared to increase in the unit bunker cost.

Advantages and disadvantages from enforcing emission restrictions within emission control areas

Purpose Emissions produced by oceangoing vessels not only negatively affect the environment but also may deteriorate health of living organisms. Several regulations were released by the International Maritime Organization (IMO) to alleviate negative externalities from maritime transportation. Certain polluted areas were designated as “Emission Control Areas” (ECAs). However, IMO did not enforce any restrictions on the actual quantity of emissions that could be produced within ECAs. This paper aims to perform a comprehensive assessment of advantages and disadvantages from introducing restrictions on the emissions produced within ECAs. Two mixed-integer non-linear mathematical programs are presented to model the existing IMO regulations and an alternative policy, which along with the established IMO requirements also enforces restrictions on the quantity of emissions produced within ECAs. A set of linearization techniques are applied to linearize both models, which are further solved using the dynamic secant approximation procedure. Numerical experiments demonstrate that introduction of emission restrictions within ECAs can significantly reduce pollution levels but may incur increasing route service cost for the liner shipping company. Design/methodology/approach Two mixed-integer non-linear mathematical programs are presented to model the existing IMO regulations and an alternative policy, which along with the established IMO requirements also enforces restrictions on the quantity of emissions produced within ECAs. A set of linearization techniques are applied to linearize both models, which are further solved using the dynamic secant approximation procedure. Findings Numerical experiments were conducted for the French Asia Line 3 route, served by CMA CGM liner shipping company and passing through ECAs with sulfur oxide control. It was found that introduction of emission restrictions reduced the quantity of sulfur dioxide emissions produced by 40.4 per cent. In the meantime, emission restrictions required the liner shipping company to decrease the vessel sailing speed not only at voyage legs within ECAs but also at the adjacent voyage legs, which increased the total vessel turnaround time and in turn increased the total route service cost by 7.8 per cent. Research limitations/implications This study does not capture uncertainty in liner shipping operations. Practical implications The developed mathematical model can serve as an efficient practical tool for liner shipping companies in developing green vessel schedules, enhancing energy efficiency and improving environmental sustainability. Originality/value Researchers and practitioners seek for new mathematical models and environmental policies that may alleviate pollution from oceangoing vessels and improve energy efficiency. This study proposes two novel mathematical models for the green vessel scheduling problem in a liner shipping route with ECAs. The first model is based on the existing IMO regulations, whereas the second one along with the established IMO requirements enforces emission restrictions within ECAs. Extensive numerical experiments are performed to assess advantages and disadvantages from introducing emission restrictions within ECAs.

The green vessel schedule design problem: consideration of emissions constraints

The fluctuating demand of international seaborne trade, overcapacity, and increasing attention to environmental issues force liner shipping companies to improve efficiency of their operations, while complying with the established emissions limitations. This paper proposes a mathematical model for the green vessel scheduling problem, imposing constraints on emissions produced by a vessel at each voyage leg of the liner shipping route. The original mixed integer non-linear mathematical model is linearized and solved efficiently using CPLEX. Numerical experiments are conducted to demonstrate changes in the vessel schedule that a liner shipping company has to make for a given shipping route, when emissions constraints are imposed.

Liner ship route schedule design with port time windows

This paper examines a practical tactical liner ship route schedule design problem, which is the determination of the arrival and departure time at each port of call on the ship route. When designing the schedule, the availability of each port in a week, i.e., port time window, is incorporated. As a result, the designed schedule can be applied in practice without or with only minimum revisions. This problem is formulated as a mixed-integer nonlinear nonconvex optimization model. In view of the problem structure, an efficient holistic solution approach is proposed to obtain global optimal solution. The proposed solution method is applied to a trans-Atlantic ship route. The results demonstrate that the port time windows, port handling efficiency, bunker price and unit inventory cost all affect the total cost of a ship route, the optimal number of ships to deploy, and the optimal schedule.

Containership scheduling with transit-time-sensitive container shipment demand

This paper examines the optimal containership schedule with transit-time-sensitive demand that is assumed to be a decreasing continuous function of transit time. A mixed-integer nonlinear non-convex optimization model is first formulated to maximize the total profit of a ship route. In view of the problem structure, a branch-and-bound based holistic solution method is developed. It is rigorously demonstrated that this solution method can obtain an ε-optimal solution in a finite number of iterations for general forms of transit-time-sensitive demand. Computational results based on a trans-Pacific liner ship route demonstrate the applicability and efficiency of the solution method.

Liner ship route capacity utilization estimation with a bounded polyhedral container shipment demand pattern

This paper aims to estimate capacity utilization of a liner ship route with a bounded polyhedral container shipment demand pattern, arising in the liner container shipping industry. The proposed maximum and minimum liner ship route capacity utilization problems are formulated as a linear programming model and a min–max model, respectively. We examine two fundamental properties of the min–max model. These two nice properties enable us to develop two ε-optimal global optimization algorithms for solving the min–max model, which find a globally ε-optimal solution by iteratively cutting off the bounded polyhedral container shipment demand set with a cut. The latter algorithm overcomes non-convexity of the remaining feasible demand set generated by the former algorithm via a novel hyperplane cut. Each hyperplane cut can assure that the current vertex of the polyhedral demand set is cut off, whereas solutions that may improve the current one by more than a factor of ε are retained. Extensive numerical experiments for problems larger than those encountered in real applications demonstrate the computational efficacy of the latter algorithm.

Robust schedule design for liner shipping services

This paper examines the design of liner ship route schedules that can hedge against the uncertainties in port operations, which include the uncertain wait time due to port congestion and uncertain container handling time. The designed schedule is robust in that uncertainties in port operations and schedule recovery by fast steaming are captured endogenously. This problem is formulated as a mixed-integer nonlinear stochastic programming model. A solution algorithm which incorporates a sample average approximation method, linearization techniques, and a decomposition scheme, is proposed. Extensive numerical experiments demonstrate that the algorithm obtains near-optimal solutions with the stochastic optimality gap less 1.5% within reasonable time.

Liner ship route schedule design with sea contingency time and port time uncertainty

This paper deals with a tactical-level liner ship route schedule design problem which aims to determine the arrival time of a ship at each portcall on a ship route and the sailing speed function on each voyage leg by taking into account time uncertainties at sea and at port. It first derives the optimality condition for the sailing speed function with sea contingency and subsequently demonstrates the convexity of the bunker consumption function. A mixed-integer non-linear stochastic programming model is developed for the proposed liner ship route schedule design problem by minimizing the ship cost and expected bunker cost while maintaining a required transit time service level. In view of the special structure of the model, an exact cutting-plane based solution algorithm is proposed. Numerical experiments on real data provided by a global liner shipping company demonstrate that the proposed algorithm can efficiently solve real-case problems.

Minimizing fuel emissions by optimizing vessel schedules in liner shipping with uncertain port times

We consider the problem of designing an optimal vessel schedule in the liner shipping route to minimize the total expected fuel consumption (and emissions) considering uncertain port times and frequency requirements on the liner schedule. The general optimal scheduling problem is formulated and tackled by simulation-based stochastic approximation methods. For special cases subject to the constraint of 100% service level, we prove the convexity and continuous differentiability of the objective function. Structural properties of the optimal schedule under certain conditions are obtained with useful managerial insights regarding the impact of port uncertainties. Case studies are given to illustrate the results.

Liner Shipping Connectivity and Port Infrastructure as Determinants of Freight Rates in the Caribbean

The Caribbean basin lies at the cross roads of major east-west and north-south liner shipping routes. A number of regional ports have been able to take advantage of their geographical position. In other ports, however, the limited scale of hinterlands and the de facto monopolistic situation of ports in Small Island States have had a detrimental effect on port development. Port infrastructure endowment varies between highly equipped global transhipment hubs and rudimentary ports with wooden quays. By the same token, the supply of regular shipping services ranges between highly interconnected routes on the one side, and Small Island States that are heavily dependent on a few limited feeder services on the other. At the same time, freight rates in the region dispose of a high variability. The paper analyses the impacts of port infrastructure and liner shipping connectivity on intra-Caribbean freight rates. The structure of liner shipping services, port infrastructure endowment and liner shipping freight rates are closely related to each other. The paper will analyse these relationships. The empirical methodology includes principal component analysis and ordinary least-squares regressions.

Structure, conduct and performance on the major liner shipping routes 1

Market concentration on the major container shipping routes has the potential to reduce contestability, impede effective competition and, as a consequence, inhibit the positive relationship between trade and economic growth. This development could also hamper the ability of economic regions to realize their respective competitive and comparative advantages. Within this context, the structure-conduct-performance (SCP) framework is used to analyse liner shipping dynamics in the transpacific, Europe–Far East and transatlantic trade routes. The analysis finds no conclusive evidence that either the increased concentration of slot capacity or the attempts by shipping lines to boost potential slot capacity (mainly through collaborative arrangements) lead to improved financial performance. The paper concludes that, despite high and increasing concentration among carriers on each of the trade routes analysed, these markets remain contestable.

Containerization and the port of Hong Kong in the 1970s

Summary The traditional focus of Far Eastern liner shipping routes and a classic entrepot among the world's ports, the port of Hong Kong, with characteristic adaptability, moved quickly to become one of the major container ports of Southeast Asia. This paper examines the issues and events which conditioned the decision to construct the Kwai Chung container terminal, the characteristics of shipping and cargo flows using this and other terminals of the port at the time of the introduction of full container capability and the impact of the new technology on the operational and morphological aspects of the port.