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Conventionally, shipping companies have invested in large ships to achieve economies of scale. More recently, high speed ships have been proposed as a means of achieving timely service for customers and improving shipping performance. Yet another solution offered here is to boost the cargo handling speed at port allowing for a higher number of annual round trips. Both the cost efficiency and timeliness of shipping service can be improved. The economic trade‐offs between the investments in cargo handling and ship propulsion technologies are formally analysed by taking the round trip frequency as the key to performance. The theoretical analyses as well as the practical cases studied indicate that investments in cargo handling technology, such as automation of container terminal operations and hatchless self‐loading ships, have indeed considerable profit‐making potential for shipping companies. Other technology investment opportunities appear less promising: ship propulsion due to energy consumption and environmental concerns; and larger ships due to low customer responsiveness and risks of low capital productivity.

This paper aims to study the implication of the stochastic gross-profit-per-day objective on the ship profitability and the ship capacity and speed.

The paper has used the mathematical model and the solution methodology given by El Noshokaty, 2013, 2014, 2017a, 2017b, and SOS, 2019.

The paper finds that if the ship owner follows the rate concept and the cargo demand forecast, he can improve the profitability of his company and be able to select the proper capacities and speeds for the ships used.

The findings are not only useful for the shipping or other cargo transport companies but also for businesses like gas reservoir development, car assembly lines in the industry, cooperative farming and crop harvesting in agriculture, port cargo handling in trade and road paving in construction.

The contribution of this paper lies in notifying the ship owners of the possible profitability improvement and the consequences of building ships of larger capacities and slower speeds.

Based on past studies on the bank effect, the purpose of this paper is to use hydrodynamic principles to simulate the overtaking and the head-on encounter phenomenon of two ships.

The ship model used in this study was established through a computer aided design (CAD) tool. Computational fluid dynamics (CFD) package was used to simulate the hydrodynamic interaction effect of the overtaking and the head-on encounter situation between two ships of different speeds. The conditions for simulation include such parameters as the speed of the ship model, the distance between the ships, and the navigation time.

A chart is also used to demonstrate the two ships ' distribution of flow field and pressure, and to continually compare the changes in the sway force and the yaw speed. A relationship diagram of the overtaking and the head-on encounter process is also established to serve as a reference in maritime science in terms of research regarding the complex fluid dynamics that occurs when ships are merged with the sea.

The application of CFD simulation results presented in this study for the ship-ship interaction support the following major conclusions: first, it is evident from the two analysis charts of angular velocity, and sway force that the cycle gradually becomes shorter with the decrease of speed of the V1 vessel during the overtaking and the head-on process; this phenomenon is most significant when the ship width is at 0.5B. Second, the ship-ship interaction increase significantly for a S2S value of 0.5B. Thus, the results indicate that the ship-ship interaction effects must be taken into consideration when performing ship handling maneuvers involving passing and meeting.

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.

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 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.

This study does not capture uncertainty in liner shipping operations.

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.

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 purpose of this study is to analyze the effect of China’s potential domestic emission control area (DECA) with 0.1 per cent sulphur limit on sulphur emission reduction.

The authors calculate the fuel cost of a direct path within the DECA and a path that bypasses the DECA for ships that sail between two Chinese ports in view of the DECA. Ships adopt the path with the lower cost and the resulting sulphur dioxide (SO₂) emissions can be calculated. They then conduct sensitivity analysis of the SO₂ emissions with different values of the parameters related to sailing distance, fuel price and ships.

The results show that ships tend to detour to bypass the DECA when the distance between the two ports is long, the ratio of the price of low sulphur fuel and that of high sulphur fuel is high and the required time for fuel switching is long. If the time required for fuel switching is less than 12 h or even 24 h, it can be anticipated that a large number of ships will bypass the DECA, undermining the SO₂ reduction effect of the DECA.

This study points out the size and shape difference between the emission control areas in Europe and North America and China’s DECA affects ships’ path choice and SO₂ emissions.

This paper aims to examine containership routing and speed optimization for maritime liner services. It focuses on a realistic case in which the transport demand, and consequently the collected revenue from the visited ports depend on the sailing speed.

The authors present an integer non-linear programming model for the containership routing and fleet sizing problem, in which the sailing speed of every leg, the ports to be included in the service and their sequence are optimized based on the net line's profit. The authors present a heuristic approach that is based on speed discretization and a genetic algorithm to solve the problem for large size instances. They present an application on a line provided by COSCO in 2017 between Asia and Europe.

The numerical results show that the proposed heuristic approach provides good quality solutions after a reasonable computation time. In addition, the demand sensitivity has a great impact on the selected route and therefore the profit function. Moreover, the more the demand is sensitive to the sailing speed, the higher the sailing speed value.

The vessel carrying capacity is not considered in an explicit way.

This paper focuses on an important aspect in liner shipping, i.e. demand sensitivity to sailing speed. It brings a novel approach that is important in a context in which sailing speed strategies and market volatility are to be considered together in network design. This perspective has not been addressed previously.

Ship route prediction (SRP) is a quite complicated task, which enables the determination of the next position of a ship after a given period of time, given its current position. This paper aims to describe a study, which compares five families of multiclass classification algorithms to perform SRP.

Tested algorithm families include: Naive Bayes (NB), nearest neighbors, decision trees, linear algorithms and extension from binary. A common structure for all the algorithm families was implemented and adapted to the specific case, according to the test to be done. The tests were done on one month of real data extracted from automatic identification system messages, collected around the island of Malta.

Experiments show that K-nearest neighbors and decision trees algorithms outperform all the other algorithms. Experiments also demonstrate that linear algorithms and NB have a very poor performance.

This study is limited to the area surrounding Malta. Thus, findings cannot be generalized to every context. However, the methodology presented is general and can help other researchers in this area to choose appropriate methods for their problems.

The results of this study can be exploited by applications for maritime surveillance to build decision support systems to monitor and predict ship routes in a given area. For example, to protect the marine environment, the use of SRP techniques could be used to protect areas at risk such as marine protected areas, from illegal fishing.

The paper proposes a solid methodology to perform tests on SRP, based on a series of important machine learning algorithms for the prediction.

Economies of scale drive container ship owners towards ordering larger vessels. Terminals need to ensure a safe (un)loading operation of these vessels, which can only be guaranteed if the mooring equipment is not overloaded (lines, fenders and bollards) and if the motions of the vessel remain below set limits, under external forces. This paper aims to focus on the passing vessel effect as a potential disturbing factor in the Port of Antwerp.

Motion criteria for allowing safe (un)loading of container vessels are established by considering the container handling process and existing international standards (PIANC). A case study simulation is presented where the behaviour of the moored vessel under ship passages is evaluated. Starting from a representative event, the effect of changes in passing speed and distance is discussed.

The study illustrates the influence of passing velocity and distance on the behaviour of the moored vessel, showing that when passing speeds are higher and/or distances lower than the reference event, safety limits are potentially exceeded. Possible mitigating measures, including the use of stiffer mooring lines and/or a change in arrangement, are discussed.

This paper serves as a basis for future research on safety criteria and optimisation of the mooring equipment and configuration to deal with passing vessel effects.

The presented results can be used by ship and terminal designers to gain familiarity with passing vessel effects and adopt suggested best practice.

By restricting the motions of the passing vessels, the focus and general well-being of the crane operator is enhanced, as is the safety of workers.

The paper provides a unique combination of container fleet observation, safety criteria establishment and case study application.

SINCE the Report of the investigations into the causes and circumstances of the accident to R.101 do not bring out any noticeably new facts, and in general can be said to bear out the statements made and conclusions arrived at m the article on the accident published in AIRCRAFT ENGINEERING, Vol. II, November, 1930, pp. 278–280, it does not appear necessary to publish here any extended summary of it, particularly as this has been amply done elsewhere. It may, however, be well to give the authenticated figures of the weight and lift of the airship, as given in the Report, as they differ somewhat from the estimates published in the article already referred to. As originally designed, the hull was 732 feet long, with a maximum diameter of 132 feet, the total gasbag capacity being 4,998,500 cubic feet, giving a gross lift of 148 6 tons. The fixed weights amounted to 113·6 tons, leaving a useful lift of 35 tons, instead of the 60 tons for which the specification had called. To remedy this deficiency the servo control and certain fittings were removed, giving a gain of 2·3 tons, and the gasbag wiring was let out, giving a further gain of 3·4 tons; the total gain from these modifications being 5·7 tons. In addition to these alterations, an extra bay (8a) containing a gasbag with a opacity of 510,300 cubic feet was inserted, which resulted in a further net gain of 8·6 tons. After these modifications the length of the hull was 777 feet, the maximum diameter remaining the same as before, and the total gasbag capacity had been increased to 5,508,800 cubic feet, giving a gross lift of 167·2 tons. The fixed weights now amounted to 117·9 tons, leaving a useful lift of 49·3 tons.

The author's aim is to offer a revolutionary method – the non‐rocket transfer of energy and thrust into Space with distances of millions of kilometers.

The author develops the theory and makes the computations.

The method is more efficient than transmission of energy by high‐frequency waves.

The method may be used for space launch and for acceleration of spaceships and probes to very high speeds, up to relativistic speed by current technology.

The research presented contains prospective projects which illustrate the possibilities of the suggested method.