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With the development of green tribology in the shipping industry, the application of water lubrication gradually replaces oil lubrication in stern bearings and thrust bearings. In terms of large-scale and high-speed ships, water-lubricated bearings with high performance are more strictly required. However, due to the lubricating medium, water-lubricated bearings have many problems such as friction, wear, vibration, noise, etc. This review focuses on the performance of marine water-lubricated bearings and their failure prevention mechanism. Furthermore, the research of marine water-lubricated bearings is reviewed by discussing its lubrication principle, test technology, friction and wear mechanism, and friction noise generation mechanism. The performance enhancement methods have been overviewed from structure optimization and material modification. Finally, the potential problems and the perspective of water-lubricated bearings are given in detail. [ABSTRACT FROM AUTHOR]

In recent years, the inland river shipping industry in China has been facing the pressure to comply with 'low carbon shipping' policies. Solar energy as one of the most widely used new energy sources has attracted more and more attention in the shipping industry. In 2015, the researchers from Wuhan University of Technology have successfully applied solar energy in an inland river 800PCC (Pure Car Carrier) – 'Anji204'. The present article described the photovoltaic (PV) generation system which was installed on board the ship and reported the results of actual navigation trials on the testing leg, Yangtze River. On the basis of the collected data, the main research purpose is to evaluate the greenhouse gas (GHG) emission and fuel consumption after introduced solar energy into ship energy system by using Energy Efficiency Design Index (EEDI) analysis. The results show that the ship EEDI reduced from 55.09 g_CO2/ton·nmile to 52.02 g_CO2/ton·nmile, decreased by about 5.57%. In addition, it can reduce the fuel consumption by an average about 16 tons per year. Therefore, the utilisation of solar energy in ships can help the inland river shipping industry to meet the 'low carbon shipping' policies. [ABSTRACT FROM AUTHOR]

• Analyse the risks of maritime supply chains from different perspectives. • Develop an advanced risk analysis method to tackle the uncertainty in risk data. • Compare risk analysis results by using different methods to demonstrate the advantages of the newly proposed one. • Conduct an empirical study to provide useful insights for the identification and control of high risks. This paper aims to develop a novel model to assess the risk factors of maritime supply chains by incorporating a fuzzy belief rule approach with Bayesian networks. The new model, compared to traditional risk analysis methods, has the capability of improving result accuracy under a high uncertainty in risk data. A real case of a world leading container shipping company is investigated, and the research results reveal that among the most significant risk factors are transportation of dangerous goods, fluctuation of fuel price, fierce competition, unattractive markets, and change of exchange rates in sequence. Such findings will provide useful insights for accident prevention. [ABSTRACT FROM AUTHOR]

The so-called "green ship" is being regarded as a potential solution to the problems that the shipping industry faces, such as energy conservation and environmental protection. Some new features, such as integrated renewable energy application, biomimetic materials, and antifriction and wear resistant coating have been accepted as the typical characteristics of a green ship, but the tribology problems involved in these domains have not been precisely redefined yet. Further, the related research work is generally focused on the technology or material itself, but not on the integration of the applicable object or green ship, marine environment, and tribological systematical analysis from the viewpoint of the energy efficiency design index (EEDI) and ship energy efficiency management plan (SEEMP) improvements. Aiming at the tribology problems of the green ship, this paper reviews the research status of this issue from three specific domains, which are the tribology problems of the renewable energy system, tribological research for hull resistance reduction, and energy efficiency enhancement. Some typical tribological problems in the sail‐auxiliary system are discussed, along with the solar photovoltaic system and hull drag reduction in traditional marine mechanical equipment. Correspondingly, four domains that should be further considered for the future development target of the green ship are prospected. [ABSTRACT FROM AUTHOR]

Recently, the melting of Arctic sea ice and development of maritime technology are enabling the regular voyages in Arctic waters. However, the Arctic maritime transportation system (AMTS) is a complex and dynamic system with respect to human, technical, environmental and organizational issues. For example, ships operating in Arctic waters suffer severe weather conditions, fully and partially ice-covered waters, and are also difficult to search and rescue in ice-covered Arctic waters due to remoteness from lands. These risk factors will influence the safety and security of ships operating in Arctic waters. For this, this paper identifies potential risk influencing factors (RIFs) for the AMTS from human, technical (ship), environmental and organizational aspects. An analytical hierarchy process (AHP) method is used to analyze the hierarchical relationships and calculate the relative importance of the selected RIFs. Due to the complexity and uncertainty involved in the comprehensive analysis of RIFs for the AMTS, fuzzy sets are incorporated into AHP analysis to represent and treat the epistemic uncertainty. The identified critical RIFs in this study can be used to propose specific guidance for the operations of crews on board, ship owners, and ship managers. [ABSTRACT FROM AUTHOR]

A ship that is not under control (NUC) is a typical incident that poses serious problems when in confined waters close to shore. The emergency response to NUC ships is to select the best risk control options, which is a challenge in restricted conditions (e.g., time limitation, resource constraint, and information asymmetry), particularly in inland waterway transportation. To enable a quick and effective response, this article develops a three-stage decision-making framework for NUC ship handling. The core of this method is (1) to propose feasible options for each involved entity (e.g., maritime safety administration, NUC ship, and ships passing by) under resource constraint in the first stage, (2) to select the most feasible options by comparing the similarity of the new case and existing cases in the second stage, and (3) to make decisions considering the cooperation between the involved organizations by using a developed Bayesian network in the third stage. Consequently, this work provides a useful tool to achieve well-organized management of NUC ships. [ABSTRACT FROM AUTHOR]

Groundings are frequently occurring accidents that pose a serious risk in inland waterways. This paper proposes a flexible decision-support solution for grounded ships in the Yangtze River. The basis of the proposed method is to develop an influence diagram based on a three-layer decision-making framework, to consider the effectiveness of the intervention measures by adding two nodes and establishing the associated conditional probability tables, and to merge the influence diagram and the intervention measures as a flexible decision-support solution. The merits of the proposed method include the intuitive representation of how the influencing factors affect the alternatives using a graphical structure, the flexibility to implement and to consider the intervention measures for grounded ships, and the ability to deal with uncertainty in both numerical data and qualitative information. The results of the case study showed that it is unanimous with the real situations and the intervention measures should be considered to make effective and accurate decision-making for grounding ships. Consequently, the method presented in this paper provides a practical and flexible decision-support solution for grounded ships. [ABSTRACT FROM AUTHOR]

Environmental problems that seriously affect both natural systems and social development of human beings have drawn extensive attention from governing authorities all around the world, and become an urgent issue to be addressed. Ports play a significant role in the international shipping which inevitably influence the global environment. Thus, the concept of green port is developed to mitigate the negative impacts of inappropriate port operations on environment. This paper analyzes the current status of green port development worldwide. An evaluation model for quantitative measurement of green port development is established based on the Drivers, Pressures, States, Impacts and Responses (DPSIR) framework. The weight of each index composing the evaluation model is calculated through an analytical hierarchy process method, and the evaluation results of the investigated ports with respect to each index are aggregated using an evidential reasoning approach. The evaluation model is further demonstrated through a comparative analysis of five major ports in China. The novel model developed along with the methods applied in this paper can provide significant insights for the comparative evaluation on the development of green ports in other countries and/or regions, as well as a powerful tool to conduct self-assessment of green port development. [ABSTRACT FROM AUTHOR]

Melting of sea ice in Arctic areas has opened up new horizons for the development of Arctic Marine Transportation Systems (AMTS). An icebreaker assists a single ship if the ice classification of the ship does not meet the ice conditions. With the increase of the number of ships and escort operations, the risks of collisions between escorting ships (icebreakers) and escorted ships have also increased. In view of this, a calculation model of the safety distance and collision risks between escorting and escorted ships is proposed in this paper in order to facilitate safe navigation in Arctic ice-covered waters. The aim of the paper is to analyze features of navigation concerning icebreakers and escorted ships in escort operations under continuous icebreaking conditions, where a quantitative model is proposed to calculate safety distances under varying ice conditions based on the ship-following theory. The proposed model is able to quantify safety distance intervals at an acceptable collision frequency under varying ice conditions, as well as the movement characteristics of icebreakers and escorted ships. A case study is carried out to calculate the safety distance between “YONG SHENG” and “50 LET POBEDY”. The results show that the model can accurately calculate the safety distance between “YONG SHENG” and “50 LET POBEDY”, which can provide theoretical guidance for ice navigation. [ABSTRACT FROM AUTHOR]

Recently, the melting of sea ice due to global warming has made it possible for merchant ships to navigate through Arctic Waters. However, Arctic Marine Transportation System remains a very demanding, dynamic and complex system due to challenging hydro-meteorological conditions, poorly charted waters and remoteness of the area resulting in lack of appropriate response capacity in case of emergency. In order to ensure a proper safety level for operations such as ship transit within the area, a risk analysis should be carried out, where the relevant factors pertaining to a given operation are defined and organized in a model. Such a model can assist onshore managers or ships’ crews in planning and conducting an actual sea passage through Arctic waters. However, research in this domain is scarce, mainly due to lack of data. In this paper, we demonstrate the use of a dataset and expert judgment to determine the risk influencing factors and develop a probabilistic model for a ship besetting in ice along the Northeast Passage. For that purpose, we adopt Bayesian belief Networks (BBNs), due to their predominant feature of reasoning under uncertainty and their ability to accommodate data from various sources. The obtained BBN model has been validated showing good agreement with available state-of-the-art models, and providing good understanding of the analyzed phenomena. [ABSTRACT FROM AUTHOR]

The global shipping industry faces huge pressure to reduce its greenhouse (GHG) emissions due to the International Maritime Organization (IMO) has introduced strict regulations to decrease GHG emissions from ships. New energy sources can provide a solution for green shipping because they have the advantages of abundant, renewable and clean. This paper examines the current progress made regarding the integration of new energy sources into conventional ship power systems, including solar energy, wind energy and fuel cells. It also discusses the possibilities for using the aforementioned three new energy sources in ship power systems ranging from technical principles to subsequent applications. Furthermore, basic working theories of new energy sources, application methods, existing new energy ships and core technologies required are summarized in detail. The integration of new energy sources into traditional ship power systems has enormous potential to bring the shipping industry in line with international regulatory requirements and is set to become a key focus of ship-related researches in the immediate future. [ABSTRACT FROM AUTHOR]