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Empty container repositioning is an important issue in the liner shipping industry. Generally stated, two groups of mathematical models have been proposed to tackle this issue. The first group aims to derive time‐dependent origin‐destination matrices that specify the number of empty containers to be repositioned at a decision epoch; the second group aims to develop effective state‐feedback control policies consisting of dynamic decision‐making rules. There is, however, a lack of research into the comparison of these two groups, especially with regard to realistic cases subject to uncertainties. The purpose of this paper is to evaluate and compare the performances of some typical repositioning policies from these two groups and to shed light on their relative merits and suitability in various realistic scenarios.

Based on a literature review, the paper classifies the current empty container repositioning policies into two categories: origin‐destination (OD) based solutions and state‐based dynamic rules. Typical policies are selected from these two categories and then evaluated using a simulation tool. A range of scenarios are designed based on realistic cases considering the stochastic and dynamic nature of liner services. A comprehensive set of simulation experiments are conducted and analysed; and the relative merits and suitability of the repositioning policies are identified.

Through a carefully designed comparative study, several research findings are obtained with regard to how the performances of different types of empty container repositioning policies are affected by various factors such as structure of service route, uncertainty of daily demands, and parametric optimisation methods.

The study makes a good attempt to analyse the suitability of different empty container repositioning policies in different scenarios. This is an area that has lacked investigation. The research findings can help shipping companies and other relevant stakeholders better understand the relative merits of different empty container repositioning policies and better tackle the challenges in operating the container shipping system.

A port plays a crucial role in total logistics chain by conducting its function as a gateway for inbound (import) and outbound (export) cargo operations. The port has traditionally been regarded as a connecting place where handles ships on one side and cargoes on the other side. These interactive functions to be carried out by the port imply that a port organization should be established, maintained and altered in a way that generates a value-adding activity to the whole logistics chain. This paper aims to suggest an alternative direction for a port organization in context of changing global logistics environment so as to be better prepared for the ever-changing business horizon. Such an attempt will provide global logistics and port management with a strategic insight into innovative and responsive port organizational strategies.

This article aims to investigate and model the effects of welding-generated thermal cycle on the resulting residual stress distribution and its role in the initiation and propagation of fatigue failure in thick shaft sections.

Experimental and numerical techniques were applied in the present study to explore the relationship(s) between welding residual-stress distribution and fatigue failure characteristics in a hydropower generator shaft. Experimental techniques included stereomicroscopy, optical and scanning electron microscopy (SEM), chemical analysis and mechanical testing. Finite element modelling (FEM) was used to model the shaft welding cycle in terms of thermal (temperature) history and the associated development of residual stresses within the weld joint.

Experimental analyses have confirmed the suitability of the used material for the intended application and confirmed the failure mode to be low cycle fatigue. The observed failure characteristics, however, did not match with the applied loading in terms of design stress levels, directionality and expected crack imitation site(s). FEM results have revealed the presence of a sharp stress peak in excess of 630 MPa (about 74% of material's yield strength) around weld start point and a non-uniform residual stress distribution in both the circumferential and through-thickness directions. The present results have shown very close matching between FEM results and observed failure characteristics.

The present article considers an actual industrial case of a hydropower generator shaft failure. Present results are valuable in providing insight information regarding such failures as well as some preventive design and fabrication measures for the hydropower and other power generation and transmission sector.

The presence of the aforementioned stress peak around welding start/end location and the non-uniform distribution of residual-stress field are in contrast to almost all published results based on some uniformity assumptions. The present FEM results were, however, the only stress distribution scenario capable of explaining the failure considered in the present research.

It is claimed that port supply chain integration (PSCI), thanks to its attributes, holds a potential to trigger a port to strategically sustain performance- and competitiveness-measures through strengthening and/or reinforcing an array of port sustainability aspects. This paper aims to empirically investigate the existent influence of PSCI on economic and environmental pillars of port sustainability.

Based on a resource-based view, this paper hypothesises that PSCI has a certain impact on port “economic” sustainability (PECS) and port “environmental” sustainability (PENS). Measures of PSCI, PECS and PENS are refined and validated using data collected from the maritime logistics industry in Egypt, and structural equation modelling is employed to test the hypothetical relationships.

The results indicate that a port having adopted an integrative strategy into supply chains could enhance its cost and operational efficiency, financial and investment situation, while offering high-quality services to its customers. Similarly, PSCI is emphatically correlated with water and air pollution management, energy efficiency and green port management practices.

Having identified the acute potential of PSCI for sustainable development in maritime logistics and supply chains, this line of research allows port operators and/or authorities to better understand strategic options with which they are able to improve their sustainability practices. This paper is, however, limited only to two dimensions of sustainability by not exploring the “social” aspect of port sustainability due to data-related issues.

This line of research could be regarded as an extended application from other industrial sectors to the port industry in a way to empirically examine the inclusive relationship of PSCI with economic and environmental parameters. The findings from this research make a due contribution to the field of port sustainability in general and Egyptian ports in particular.

The maintenance of the air–water interface is crucial for the drag reduction on hydrophobic surfaces. But the air bubbles become unstable and even washed away under high speed flow, causing the failure of surface hydrophobicity. Thereby, this paper aims to understand the relations between bubble behaviors and surface properties, flow conditions and to discover new methods to maintain the air–water interface.

Bubble properties on hydrophobic surfaces were characterized using single-component multiphase lattice Boltzmann simulation. Three equations of state (EOSs), including the Peng–Robinson, Carnahan–Starling and modified Kaplun–Meshalkin EOSs, were incorporated to achieve high density ratios.

Both the static and dynamic properties of bubbles on hydrophobic surfaces were investigated and analyzed under different flow conditions, solid–liquid interactions and surface topology.

By revealing the properties of bubbles on hydrophobic surfaces, the effects of flow conditions and surface properties were characterized. The maintenance method of air–water interface can be proposed according to the bubble properties in the study.

The purpose of this paper is to investigate the tribological performance and mechanisms of BN/calcium borate nanocomposites (BCBNs) as additives in lubricating oil.

BCBNs were prepared by heterogeneous deposition method. And the morphology and structure of samples were analysed by transmission electron microscopy, Fourier transform infrared spectra and X-ray powder diffraction pattern. The maximum non-seizure load (PB) of samples was tested using four-ball friction tester. The average friction coefficients and wear tracks were obtained. In addition, tribological mechanism was also investigated using optical microscope, energy dispersive spectroscopy and X-ray photoelectron spectroscope.

It was found that the nanocomposites present core-shell nanostructure with the thickness of shell around 12 nm and the diameter of particles 100-200 nm, and tribological tests indicate that the PB value of BCBNs was increased by 113 per cent, whereas the average friction coefficient was decreased by 23.6 per cent and the bloom’s wear area was also decreased by 25.2 per cent.

This paper involves investigation on tribological properties and mechanism of the BCBNs with core-shell structure.

The paper aims to propose a stability analysis method based on region-of-attraction (ROA) overlapping to evaluate the flight stability of the possible sudden damage process and guarantee flight safety in extreme cases.

First, according to the two flight conditions before and after damage which the aircraft may encounter, flight dynamical models are built and fitted by polynomial equation for subsequent ROA analysis. And then, the ROA overlapping estimation method based on V-s iteration is presented to complete the stability analysis of such airplane sudden damage process.

Finally, in the presence of control surface damage, case aircraft flight stability is analyzed and simulated to verify the effectiveness of the proposed method.

The proposed method can be used for stability check during the aircraft control law design, or for further completing the design of the emergency stable controller design.

Compared with previous studies on sudden damage process of aircraft, to the best of the authors’ knowledge, this is one of the pioneer studies in which the ROA and ROA overlapping concept has been introduced. This study on stability analysis of aircraft sudden damage process could further develop the theory of emergency stable control.

In the shipping industry, both sales and purchases of second-hand ships and freight transport services are prevalently tailormade and traded with intense bilateral negotiations. Price bargaining is the key step of this negotiation process and plays a crucial role in determining mutually agreed prices. Despite its cruciality and applicability, the price bargaining has yet received due conceptual and/or theoretical attention in the shipping literature. This paper attempts to conceptually examine the role of bargaining in shipping transaction prices and subsequently puts forward directions for future research. In doing so, the paper focuses on two types of transactions taking place in shipping markets: asset market trading of second-hand vessels and service market trading shipping freights.

The paper begins with a systematic literature review of price bargaining in the field of economics and management disciplines from a game-theoretic perspective. This approach does logically lead to the establishment of a conceptual framework for price bargaining in shipping sub-markets as a step toward having taken into consideration a variety of heterogeneities commonly present in trading activities and market dynamics.

A set of research areas has been consequently identified where price bargaining and mechanisms for the shipping freight and asset markets could be further explored and analyzed in a way to make better pricing decisions under a more tangible framework.

One of the critical challenges when using bargaining mechanisms to make a decision on pricing shipping services and assets is how to operationalize the study for empirical investigation as some of the factors are internal information of the players and are not adequately revealed to externals: that is, an imperfect information sharing case. The current study aims, however, not to conduct an empirical analysis but to initiate a conversation among maritime economists by bringing their attention to this not-yet fully explored and potentially impactful field of research and by asking them to treat bargaining from a perspective for pricing shipping assets and services. It is claimed that, by doing so, one could better understand price differences between individual contracts.

This study would be considered the first of its kind to provide a detailed survey of the bargaining theory and models from a game theoretical perspective as a theoretical lens to understand its importance and relevance in pricing shipping assets and services. It also provides a simplified operational case on utilizing bargaining in practically pricing freight services.

The literature on Maritime Transportation (MT) is experiencing a transition phase where the focus of the research is repositioning. It registered steep growth in recent years with its beginning articles on the concepts of cost minimization to the current focus on achieving sustainable operational effectiveness using Information and Communication Technologies (ICTs). Thus, this becomes a right time to investigate the trajectory of research on MT.

The proposed study aims to explore the potential of data analytics techniques such as data mining and network analytics to reflect the trajectory of research in the maritime supply chain over time. This study identifies the eight main dimensions of the research published under maritime paradigm through network analytics. The in-depth review of these dimensions rendered us to segregate them further into sub-dimensions for the ease of understanding and interpretability. Further, the text mining is employed to extract thematic evolution of the research.

The evolved themes are completely exclusive from the conventional MT research with artificial intelligence, digital storage, waste management and biofuels emerging as contemporary themes. It is found that although there are a sufficient amount of literature on sustainable port practices but their policy implications are still underexplored. The inter-dimension research is needed to achieve the motive of economic efficiency and environmental sustainability simultaneously.

The study has contributed on the methodology side of conducting literature reviews. The dimensions, sub-dimensions and themes are obtained using data analytics tools and techniques. This omits the possibility of personal bias and thus making the results verifiable.

The purpose of this paper is to explore and analyse the risks in container shipping operations from a logistics perspective. In the paper, risks associated with the three flows in logistics − information, physical, and payment flow are identified and analysed.

The use of case study method was first explained and justified. Second, risk identification was started with supporting references, several interviews were then conducted to identify and validate the potential risks in container shipping operations. A questionnaire was deployed to collect related data; and the impacts of the risks were then assessed and ranked using the method of risk mapping.

The paper has identified a total of 35 risk factors and classified them into different categories. The paper has also revealed that the risks associated with physical flows have more serious risk impacts than the other types of risks; however, one of the risk factors associated with information flow (shippers hiding cargo information) is the most significant one among all the factors.

Although many studies have been conducted on container shipping operational risks, no studies so far have approached this issue from a perspective that inclusively examines all the possible risks and comprehensively evaluates the relative importance of each of them. This study has identified the risks in container shipping operations, and analysed and ranked the level of these risks. The research further “refines” the findings of some previous studies by placing the risk factors addressed therein in a full “risk picture” which was developed systematically.