Maritime Practice Research Articles

Product transportation strategy in the presence of limited shipment capacity and purchase timing

ABSTRACT In maritime practice, shippers can order shipment capacity before knowing product demand and then transport those products via liner shipping (LS) after observing demand information, or shippers can transport them when needed via tramp shipping (TS) without pre-ordering shipment. We develop a game-theoretic model to analyse these two transportation modes, LS and TS, in the presence or absence of demand and supply shocks such as those occurring in a pandemic. Interestingly, when vessels have a sufficiently small shipment capacity, the shipper prefers LS (TS) when market uncertainty is high (low) if the following is true: (a) the market size is moderate and there are no such shocks, or (b) the market is not sufficiently large in the case of shocks. This conclusion contradicts the naïve belief that the shipper prefers LS (TS) in the case of low (high) market uncertainty. Additionally, when the market is sufficiently large, the shipper prefers TS only if dead freight rate is low and the tramp vessel’s shipment capacity is moderately greater than that of LS. It follows that, due to high freight charges or low profit, the TS mode may not be the shipper’s best choice, even if the transportation demand is very large.

Ship autonomous collision avoidance decision from the perspective of navigation practice

Navigation safety is an eternal theme for ships, and it is an inherent strategic requirement for both transportation powers and maritime powers. With the development of intelligent ships, how to make intelligent decision-making results consistent with maritime practice is the key to navigation safety. This paper constructs a complex water area collision avoidance decision-making model that conforms to maritime practice, providing autonomous collision avoidance decision-making schemes for manned or unmanned ships. Firstly, based on the nonlinear velocity obstacle method, dynamic constraints such as ship maneuverability, target ship motion uncertainty, Convention on the International Regulations for Preventing Collisions at Sea (COLREGs), and good seamanship are fully considered, and a safe collision avoidance action plan is solved in the velocity domain; Then, by introducing an overshoot coefficient to improve the line of sight method, a feasible collision avoidance decision plan is derived by searching for a resumption navigation plan based on the safe avoidance action plan; Finally, collision avoidance decision plan is optimized to achieve autonomous collision avoidance decision-making for ships. To verify the effectiveness of the proposed model, a series of case studies, which focus on different encounter situations are designed and executed, the results indicate that the outcome of the model consistently aligns with real-world scenarios, which is in line with maritime practice.

Analysis of the peculiarities of the method of combining an electronic cartographic navigation information system with a ship's radar station

The article analyses the importance of radar image overlay on the screen of an electronic charting navigation information system (ECNIS) for improving safety and efficiency of navigation. Based on a review of scientific publications and professional literature, the article discusses the technical aspects of the overlay function, its advantages and limitations, and the impact on the decision-making process of a navigator. The overlay of radar information on an electronic navigation chart ensures the integration of planned and actual data on the environment, which contributes to the increase of situational awareness of the navigator. The combination of the systems makes it possible to visually compare radar targets with cartographic objects, clarify the vessel's location, control drift and orientation, and detect navigation hazards. The overlay function is especially valuable when sailing in confined waters and in conditions of limited visibility. At the same time, the use of overlay technology is associated with a number of technical difficulties and limitations related to ensuring the accuracy of overlap, harmonisation of data formats, and synchronisation of information updates. Errors in the operation of positioning systems, direction guidance, and cartography errors can lead to inconsistencies in image layers and incorrect interpretation of the navigation situation. The issues of equipment reliability, display parameters settings, competence and training of navigators are of critical importance. It is emphasised that radar image overlay on ECDIS is an effective tool for improving safety of navigation, but it does not replace traditional navigation practices and does not eliminate the need for critical evaluation of data. Over-reliance on technology, ignoring its limitations and disregard for the principles of good maritime practice can lead to erroneous decisions and have a negative impact on safety. Further prospects for the development of technology can be associated with the improvement of information processing algorithms, optimisation of human-machine interaction, and the development of training methods. The article emphasises the need for an integrated approach combining the improvement of technical systems and the human factor to fully realise the potential of the overlay function in ensuring safety of navigation. Only a balanced use of technological innovations and traditional navigational practices can guarantee the reliability and efficiency of modern navigation

Managing port disruption through sailing speed optimization for sustainable maritime transportation

Ports, as nodes in maritime transportation, frequently face disruptions leading to congestion, adversely affecting the efficiency and sustainability of the global supply chain. This study considers the speeding-up strategy to alleviate port congestion. We model the transportation network as a closed Jackson network and adopt a tailored mean-value analysis algorithm to solve the model. To deliver the increased sailing speed, we further put forward a bi-section search algorithm. Our numerical analysis results demonstrate the feasibility of increasing speed to alleviate port congestion. However, when port congestion exceeds a certain threshold, the system faces collapse, rendering the increase in speed ineffective. Additionally, we recommend shipping companies consider using clean energy when employing the speeding-up strategy to mitigate congestion, thus safeguarding the environment. Our study combines theoretical methodologies and analytical models, providing insights regarding speeding up the vessels. The findings of this study offer guidelines for real-world sustainable maritime practice.

Practical On-Board Experience as a Significant Predictor of Positive Perception towards English Language Learning

The English language is becoming increasingly important in both English-speaking and non-English-speaking countries. In the modern age, although English language skills are not the only criterion for career development, they are an indispensable tool for career advancement or obtaining a job. The aim of this study is therefore to investigate whether experience in the professional field can be considered a significant predictor of maritime students’ attitudes towards the need to learn English. For this purpose, students of undergraduate studies of Marine Engineering at the Faculty of Maritime Studies, University of Split, with no work experience (N1=65) and students of the Special Training Programme of Marine Engineering at the Faculty of Maritime Studies with at least three years practical experience (N2=38) have been asked about their attitudes towards this issue. The participants completed a newly constructed questionnaire on the need for English as a professional language. The results show a very high reliability of the questionnaire, (r ranges from 0.83 to 0.95 with p<0.01; t<0.73 with p>0.67). Furthermore, the Mann–Whitney U test has revealed a significant difference in the attitudes between the groups of participants for five out of the six variables (p<0.01). Additionally, it can be concluded that experience is a significant predictor of attitude, which implies that English language learning is a necessity in maritime practice.

William Falconer and the Rhetoric of the Sea

This essay explores how William Falconer's A Universal Dictionary of the Marine exemplifies the “rhetoric of the sea,” which operates according to an inclusive approach to maritime knowledge, which maritime authors adopted in an effort to translate into writing a unique, physical practice at sea. Since maritime practice involved diverse processes in an environment that could not be controlled, maritime and navigation books thereby contained diverse styles and forms, from poetry, to criticism, to illustrations, to definitions, in an effort to reflect the diversity, and experience, of the sea itself. This essay places Falconer's Dictionary (1769) into a longer history of maritime and navigation books, especially dictionaries, including John Smith's Seaman's Grammar and Dictionary (1626), and the development of specialized dictionaries in English. Building on developments in “blue ecocriticism,” this essay concludes by suggesting that the eighteenth-century rhetoric of the sea provides us an understanding of the semantic and physical power of the world's oceans.

Determinants of COVID-19 Infections on Sea-Going Ships and Their Socio-Economic Consequences for Seafarers and Shipowners in Terms of Modeling Ship Emergency Procedures

The COVID-19 pandemic has caused many negative socio-economic consequences for seafarers and shipowners of such importance that, on the one hand, it inspired and, on the other hand, it became an impulse to undertake research in this direction. It seems that avoiding at least some consequences would be possible if both shipowners and ship masters operated based on safety management procedures strictly adapted to the pandemic situation. Of course, many crisis management procedures have been developed in maritime practice so far. Still, they mainly relate to such events as maritime incidents, maritime accidents, maritime disasters, oil spills, terrorist attacks, or sea piracy. However, they do not consider the specificity of a crisis situation created for the safety of the ship’s crew by the global pandemic. Its appearance made all maritime transport entities, especially shipowners, aware of the lack of preparation for such an eventuality. Based on the general recommendations of international organizations, such as the WHO (World Health Organization) or the IMO (International Maritime Organization), they began developing and implementing urgent procedures for handling ships under COVID-19 conditions. Since the recommendations were formulated generally and the pandemic spread very quickly, the prevention and response procedures for a ship found to be affected by COVID-19 were developed ad hoc and, therefore, were often flawed. Consequently, it was concluded that it is worth creating a universal model of the procedure for dealing with a sea-going ship in pandemic conditions and reducing the adverse socio-economic consequences for shipowners and seafarers. This became the primary goal of the research undertaken in this direction, and this goal was closely related to the adopted central research hypothesis. The substance of the matter comes down to the fact that knowledge of the factors causing coronavirus infections will allow the development and implementation of effective procedures for handling ships in pandemic conditions. It will also reduce the risk and consequences of coronavirus infections. COVID-19 infections can be caused by many factors that are beyond the control of the shipowner and the ship’s captain. Still, there are also those factors that they can control and thus eliminate or at least reduce the risk of contracting the coronavirus by the crew. Thus, their correct identification, ranking their importance in terms of the risk of infection, and then focusing on the elimination of the most important of them is the basis for building a universal model, in the sense of the possibility of applying to any sea-going ship in pandemic conditions. The work includes RCA (Root Cause Analysis), stratification analysis, weighted Ishikawa diagram, and Lorenz-Pareto chart. The primary sources of information used in the research came from the literature review, the analysis of normative acts, the analysis of documentation and procedures on board ships in pandemic conditions, questionnaire research, direct and focus interviews, and participant observation.

Influence of vessel upsizing on pollution emissions along Far East-Europe trunk routes.

The emissions of vessels are higher when they sail at sea than when they are at a port, and such emissions affect air quality considerably. In this study, an activity-based method was used to calculate the quantities of various pollutants emitted by large container ships sailing at optimal speed on Far East–Europe trunk routes, which cover seven of the largest economies with high population density. We determined the emission quantities of various pollutant, such as carbon dioxide (CO2), sulfide ({mathrm{SO}}_{mathrm{x}}), nitride ({mathrm{NO}}_{mathrm{x}}), and particulate matter—for the newest mega container ships deployed on the aforementioned routes by THE Alliance. This study considered vessel speed as a critical variable and found that to reduce vessel emissions, port authorities should mandate that vessels reduce their speed when entering and leaving a port. Considering maritime practice, setting the optimal speed of a vessel as 15–18 knots is the most effective method for reducing emissions. On the basis of the obtained results, appropriate recommendations are made to the International Maritime Organization, international shipping companies, and port authorities.

Realistic Dilemma and Improvement Path of Maritime Injunction

In China, the maritime injunction system has been in operation for more than 20 years since the entry into force of the "Special Maritime Procedure Law of the People's Republic of China " ( hereinafter referred to as the " Maritime Procedure Law " ). It is a creative provision for the preservation system of civil procedure law, which is applied to the field of maritime practice and aims to protect the legitimate rights and interests of applicants in " emergency situations. " Based on the discussion of the nature and function of maritime injunction, this paper makes an empirical study on the data of maritime injunction judgment documents and typical cases of maritime injunction in the past three years, analyzes the problems existing in the specific application of the system in current maritime disputes from the current situation of practice, and puts forward some suggestions on the constituent elements and procedure setting of the application of maritime injunction system.

Reflection on Maritime Practice Training of Military Health Service for cadets of Military Medical University

In order to improve the quality of Maritime Practice Training of Military Health Service for cadets of Military Medical University, firstly, this paper systematically analyzed the concept and significance of Maritime Practice Training of Military Health Service for cadets of Military Medical University, and put forward requirements for Maritime Practice Training of Military Health Service. Secondly, summarize the current experiences between our and foreign Maritime Practice Training of Military Health Service for cadets of Military Medical University. Finally, by comparing the advantages of different Maritime Practice Training of Military Health Service for cadets of Military Medical University, then put forward Reflections on Maritime Practice Training of Military Health Service for cadets of Military Medical University, pay attention to the top planning, emphasizes on the training of subject setting, pay attention to security, etc.

Cooperative Multi-Agent Control for Autonomous Ship Towing Under Environmental Disturbances

Among the promising application of autonomous surface vessels (ASVs) is the utilization of multiple autonomous tugs for manipulating a floating object such as an oil platform, a broken ship, or a ship in port areas. Considering the real conditions and operations of maritime practice, this paper proposes a multi-agent control algorithm to manipulate a ship to a desired position with a desired heading and velocity under the environmental disturbances. The control architecture consists of a supervisory controller in the higher layer and tug controllers in the lower layer. The supervisory controller allocates the towing forces and angles between the tugs and the ship by minimizing the error in the position and velocity of the ship. The weight coefficients in the cost function are designed to be adaptive to guarantee that the towing system functions well under environmental disturbances, and to enhance the efficiency of the towing system. The tug controller provides the forces to tow the ship and tracks the reference trajectory that is computed online based on the towing angles calculated by the supervisory controller. Simulation results show that the proposed algorithm can make the two autonomous tugs cooperatively tow a ship to a desired position with a desired heading and velocity under the (even harsh) environmental disturbances.

A rule-aware time-varying conflict risk measure for MASS considering maritime practice

Conflict detection is a vital step of collision prevention at sea, determining if there is a risk of collision and when to take preventing actions. This article proposes a practical Rule-aware Time-varying Conflict Risk (R-TCR) for ship collision avoidance. Considering maritime practice, the conflict risk measure takes the ship maneuverability, the COLREGs, and good seamanship into account in the conflict risk measure. Specifically, the conflict risk is formulated as a ratio of achievable maneuvers leading to a collision to all achievable maneuvers. Simulations are carried out to show the characteristics of R-TCR. The results show that the R-TCR evaluates the entire conflict risk incorporating COLREG rules, multiple targets, different maneuverability, and varying ship domains. Finally, the proposed measure is applied to analyze the collision accident between two ships. Compared with the conventional risk indicators, the proposed R-TCR can deliver extra information to users, such as providing early warning, showing the room-for-maneuver, and suggesting evasive actions. Besides, the extra information also supports collision avoidance for autonomous ships.

Hold Fast

In the world of maritime lore and practice, tattoos were both commemorative and magical. Sailors frequently tattooed the words H-OL- D F-A-S-T onto the skin above each knuckle in the hopes of strengthening their grasp on the ship’s rigging. It gave sailors an edge at saving their own lives when the winds would howl and the ship tossed wildly on the waves, and they must hold fast or be thrown into the dark cold sea. This illustrated autoethnographic work will draw on the metaphor of the ship in transit, the slippery rigging, storied magic and the dangers of the chasm below, to interrogate the idea of the academy as literal and figurative home for transnational academics. In it, I will combine words and pictures to tell two stories of being. The piece concludes with problematizing the notion of “home” as a desirable construct in the context of the academy.

Solution of the Two-vector Problem of Resource Saving on Board of the Ship

Recently, the International Maritime Organization has taken a number of design decisions aimed at reducing the consumption of marine diesel fuel, carbon dioxide and sulfur dioxide emissions. The latter can be achieved by introducing the ship's energy efficiency management plan into maritime practice, minimizing the operational coefficient of the ship's energy efficiency, and transferring maritime transport to low-sulfur fuel. In addition to the above measures, this article proposes an integrated technology for the purification of exhaust gases from ship power plants (EG SPP) and utilization of the heat of exhaust gases from the SPP. The analysis of the known technical solutions for the purification and utilization of the heat of the exhaust gas of the power plant is carried out, their shortcomings are revealed and the ways of developing a resource-saving technology are outlined. As a result of the research carried out, the main components that lead to an increase in the efficiency of sea cargo transportation and the protection of the environment have been identified. Due to the implementation of the developed integrated technology, the damage to the air basin from the EG SPP is reduced by five times.

Preparing for an Unknown Future. Autonomous Ships Versus Position of the Maritime English/IMO Standard Marine Communication Phrases(ME / IMO SMCPs) in Maritime Practice. How Are We Going to Solve this Problem?

Preparing for an Unknown Future. Autonomous Ships Versus Position of the Maritime English/IMO Standard Marine Communication Phrases(ME / IMO SMCPs) in Maritime Practice. How Are We Going to Solve this Problem?

Application of VR Virtual Reality in Navigation Teaching

This paper discusses the various factors that restrict the quality of training in maritime practice teaching, analyzes the technical characteristics of virtual reality technology, and the various advantages of virtual reality technology applied in maritime practice teaching, and on the virtual practice training system. The development process is described. The application of virtual reality technology in the practical teaching of navigation can further improve the quality of practical teaching of navigation students.

Evaluation of the accuracy of the ship location determined by GPS global positioning system on a given sea area

The current location of navigation and navigation depends heavily on global satellite navigation systems, mainly GPS (Global Position System). In actual maritime practice, the position of the ship is determined to be the most probable position and will be the center of the circle of probability containing the ship’s position. However, this is not entirely accurate because the exact position on the chart depends on many factors such as deviation of the geodetic system, the accuracy of the chart, etc. On the other hand, the probability circle contains the location. The ship is scalar, the radius of error of the probability circle depends on many factors, etc. Therefore, determining the probability location with the highest accuracy is a rather complex problem. In particular, in the waters where the safety system is not complete, the level of survey is not good: Solomon Islands, Papua New Guinea, Indonesia, Cambodia, Vietnam, etc. actual errors of GPS location operating above. The chart is much larger than the error recommended by the manufacturer. In the context of the article, the author proposes a method for determining the probability area containing the actual ship position and its orientation to improve high safety in manoeuvring and navigating vessels at sea, testing on coastal Vung Tau - Vietnam.

Experimental Research on the Impact of Anchor-Cable Tensions in Mooring Ship at Vung Tau Anchorage Area

According to the detailed planning of Southeast seaport group up with an orientation to 2030, Ba Ria - Vung Tau seaport is an international gateway (type IA), acting as an international transshipment port where commercial, industrial services are developed and facilitated in goods import and export activities. However, one of the significant obstacles to the development of the Ba Ria-Vung Tau port service industry is the lack of synchronous infrastructure of the entire port system. The leading causes of these obstacles are due to inappropriate design and investment in anchoring and lack of in-depth studies on the specific characteristics of the flow through the anchorage area. This is a big problem, because the tankers often have low freeboard, mainly affecting the flow in the mooring area. Therefore, the focus on studying the impact of the flow in the anchored area of Vung Tau on oil tankers will contribute to the maritime practice of the anchoring areas in general and in Vung Tau in particular. In this paper, the authors will focus on empirical research on an experimental model that is constructed by the uniform method to determine the anchor-cable tension of ship anchorages with different loading modes at the assumed flow rate in the anchoring areas in Vung Tau. The results obtained from experimental research and simulation by numerical methods are compared and evaluated to develop an empirical and reliable formula for anchor-cable tension with oil tankers in Vung Tau anchoring area.

Application of The KNN Algorithm in Determining the Orientation of The Probability Area Containing The Ship Position by GPS Systems on Hai Phong Coastal Area

The need for navigation for the maritime industry is also very urgent. Today, most commercial boats have receivers and positioning signal receivers, giving an accuracy of several meters. For vessels arriving at, or passing through small canals, the ability to locate with an accuracy of less than 1 meter is necessary. In these cases, the use of DGPS technology is necessary. The determination of ship location and navigation depends on global satellite navigation systems, mainly GPS systems. In maritime practice, the position of the specified vessel is considered the most probable position and will be the center of the circle of probability area containing the ship position. However, the probability area containing the ship position is scalar, the radius of error of the circle of probability area depends on many factors, such as the deviation of geodetic system, the accuracy of the chart. Therefore, the determination of the most probable position with the highest accuracy is a quite complex problem. The demand for data processing is also greater; Machine Learning is thus contributing to solving this problem. In the framework of the article, the authors propose the application of the KNN algorithm to determine the orientation of the probability area containing the ship position with the most probable positions. The objective of this study is to improve efficiency and safety in maneuvering and navigation for sea vessels and testing for Hai Phong coastal area.

Arbitration Mechanisms in Settlement of Maritime Disputes in Nigeria: Challenges and Prospects

The maritime industry is globally recognized as one of the most economically viable industry capable of facilitating sustainable development thus, amicable settlement of maritime disputes is paramount to guarantee unhindered trade and commerce environment. Arbitration is an age-long Alternative Dispute Resolution (ADR) mechanism applied in the amicable settlement of disputes in a relaxed and semi-formal environment. It is particularly suitable for resolving commercial disputes because of the enforceability of arbitral awards as depicted by the existing international arbitral jurisprudence. Various law of the Sea tribunals such as the International Tribunal for the Law of the Sea (ITLOS) or an ad hoc panels expressly recognizes arbitration as one of the models for settlement of disputes as a suitable alternative to litigation. In Africa, as nations recover from the era of ocean blindness, maritime practice and administration is prioritized to aid economic growth. The objective of this study is to evaluate application of arbitration as an ADR mechanism for settling maritime disputes in Nigeria’s maritime practices with the aim of identifying the challenges confronting Nigerian’s involvement in maritime business, particularly as it relates to application of Arbitration to dispute settlement. It was found that there are certain loopholes in relevant laws which work hardship against local businesses in cases of maritime disputes settlement. The study suggests viable solutions based on lessons from other climes to create level playing field for parties who opt for arbitration to settle maritime related disputes.