Merchant Ships Research Articles

Proposal of Optimal Operation in Ship Rolling Motion Considering Sea State Conditions

Most of the research on ship rolling motion concerns a specific type of ship, such as containerships, or analyzes sailing during certain wave characteristics, rather than the full spectrum of waves that can be encountered during the entire sea route. To date, the most frequent merchant ships in the world are general cargo ships, where the ship’s behaviour at any sea condition has a great influence on overall safety, as well as the lashing design of non-standardized cargo. For this reason, the present paper aimed to study ship-performance models, starting with concepts of the basic physics of ships and waves. Firstly, the ship’s behaviour was analyzed from a theoretical point of view, both in calm waters and when sailing in waves, but independently. Afterwards, the ship-waves system was analyzed during rolling with all variables accounted for at the same moment, with the objective of obtaining roughly realistic models. Relevant results are shown in each of the models, which may be of great interest for ship operators and, in general, for the shipping industry, so as to improve the safety of maritime transport. Finally, these results were validated with a case study.

A comparison of ship manoeuvrability models to approximate ship navigation trajectories

ABSTRACT It is essential to describe a ship’s manoeuvrability for various applications, e.g. optimal control of unmanned surface vehicles (USVs). In this study, the capability of two recognised manoeuvrability models to predict ships’ trajectories is investigated based on both simulation and open-water experiment test data. The parameters of these models are estimated by a statistical learning method. The goodness of the two estimated models for describing a merchant ship’s manoeuvrability is first studied using her manoeuvring simulation data. Then, experimental manoeuvring tests to use a USV in open water with wind and drifting effects are used to check the conventional model identification procedures. Finally, some modifications and adjustments are proposed to improve the conventional procedures. It shows that the proposed procedures can accurately derive the ship’s manoeuvrability based on experimental data.

Advances in maritime autonomous surface ships (MASS) in merchant shipping

Advances in maritime autonomous surface ships (MASS) in merchant shipping

On reliability assessment of ship machinery system in different autonomy degree; A Bayesian-based approach

Analyzing the reliability of autonomous ships has recently attracted attention mainly due to epistemic uncertainty (lack of knowledge) integrated with automatic operations in the maritime sector. The advent of new random failures with unrecognized failure patterns in autonomous ship operations requires a comprehensive reliability assessment specifically aiming at estimating the time in which the ship can be trusted to be left unattended. While the reliability concept is touched upon well through the literature, the operational trustworthiness needs more elaboration to be established for system safety, especially within the maritime sector. Accordingly, in this paper, a probabilistic approach has been established to estimate the trusted operational time of the ship machinery system through different autonomy degrees. The uncertainty associated with ship operation has been quantified using Markov Chain Monte-Carlo simulation from likelihood function in Bayesian inference. To verify the developed framework, a practical example of a machinery plant used in typical short sea merchant ships is taken into account. This study can be exploited by asset managers to estimate the time in which the ship can be left unattended. Keywords: reliability estimation, Bayesian inference, autonomous ship, uncertainty.

Austro-Hungarian merchant ships in the United States during the First World War

This article examines the fates of Austro-Hungarian merchant ships that were stranded in ports in the United States at the beginning of the First World War. The wider context of the relationship between Austria-Hungary and the United States is also analysed. The article proves the hypothesis that even though there were in fact not that many of these ships in number, they did represent a significant portion of the Austro-Hungarian passenger-liner fleet. The article also analyses the way both governments approached this issue, as well as how the owners themselves reacted with regard to the future of their ships.

중국의 여해적 정일수(鄭一嫂)와 해상권력의 구축

The South China Sea in the 19th century was the heyday of pirates. In 1805, a group of six pirates signed an agreement to establish the Pirate Federation. In addition, European merchant ships and Chinese merchant ships traveling between routes in the South China Sea were looted and engaged frequently with the Qing Dynasty's naval forces. Among the six groups, the strongest force was Hong Gi-bang (Red Flag), and the Red Flag had strong power as the leader of the Pirate Federation. This paper noted how the pirate Cheng I’s Wife became the leader of Hong Gi-bang (red flag) beyond gender and sexual norms in the pirate world and gained tremendous power in the pirate federation. In Chinese history, Madam Qing was hidden by her husbands and was not properly evaluated. Therefore, in Chapter 2 of the paper, we will look at the Chinese and Western records written about Cheng I’s Wife. In particular, important clues about her can be found in Western records, and data on Cheng I’s Wife and Chinese pirates are abundant in the autobiography of an Englishman who was kidnapped by a Chinese pirate. Chapter 3 analyzed how Cheng I’s Wife ran a pirate organization and the cause of his powerful power in the pirate society from three perspectives: husband's legacy, Article 3 of the Rules, and the religion of pirates's pirates.

Impact analysis of ECA policies on ship trajectories and emissions

This study aims to investigate the impact of emission control area (ECA) measures on ship trajectories and emissions of merchant ships. Results show that a part of merchant ships sail outside the ECA water area to avoid using more expensive low-sulfur fuel. The implementation of stricter ECA policies could reduce the SOx emissions by 31.24%–42.67% for three merchant ship types. It is found that the proportion of ship voyages outside the ECA waters could increase by 4.77%–9.44% after the implementation of stricter ECA policies. Three logit regression models are established subsequently to estimate the occurrence probability of ECA evasion behavior. Results show that the evasion probabilities of merchant ships could increase with the ship size, the ship voyage distance as well as the price gaps of marine gasoline oil (MGO) with respect to high sulfur fuel oil (HSFO).

Maximum entropy inference of seabed properties using waveguide invariant features from surface ships.

Acoustic data were recorded on two vertical line arrays (VLAs) deployed in the New England Mud Patch during the Seabed Characterization Experiment 2017 in about 75 m of water. The sound recorded during the passage of merchant ships permits identification of singular points for the waveguide invariant β for mode pairs (1,n):β1,n,for n=2,3,4,5, in the 15-80 Hz band. Using prior geophysical information and an acoustic data sample from the merchant ship KALAMATA, a geoacoustic model M of the seabed was developed. Then, using data samples from other merchant ships, a feature-ensemble maximum entropy method is employed to infer the statistical properties of geoacoustic parameter values for the sound speeds in a surface mud layer and a deep sand layer. Technical challenges include a sparsity of observed singular points, the unique identification of mode pairs for an observed singular point, and the deviation of the waveguide from horizontal stratification. A geoacoustic model M is developed that reproduced the observed β≈-1 for f < 20 Hz and mode cutoff features at about 15 Hz. The statistical low-frequency inference of the singular point structure from multiple ships provides evidence of an angle of intromission at the water sediment interface with an average sound speed ratio of about 0.986 and an average sound speed for the deeper sand layer of about 1775 m/s.

An e-learning platform for managing seafarers’ health issues on board: pilot use on the Greek shipping industry

Background: It is well known that health management on board is a major challenge for maritime authorities, shipping companies, and seafarers. This paper presents the outcomes of the pilot use of an e-learning platform for dealing with mariners’ health issues aboard.Methods: The survey took place in the Piraeus port (Attica, Greece) during November 2021-February 2022. Data were gathered from merchant ship mariners (n=41) by questionnaires at the Piraeus port, Athens, Greece. A descriptive statistical analysis was performed by the SPSS v23.0® and Microsoft excel© 365.Results: Twenty-one seafarers (51.21%) were at the age group 31-40 years old, fifteen (36.58%) were at the age group 41-50 years old, four (9.75%) were at the age group 51-60 years old and 1 participant (2.43%) was over 60 years old. Twenty-six (63.41%) of the participants were occupied on deck department while fifteen (36.58%) in the engine room. A statistically significant higher score on web-test after the use of SeaHealth platform was confirmed by paired t test (p&lt;0.001) (Figure 3).Conclusions: The participants who used the e-learning platform improved their knowledge on first aid, increased their basic skills on medical care, and achieved more confidence in handling emergencies effectively aboard.

An Unscented Kalman Filter Online Identification Approach for a Nonlinear Ship Motion Model Using a Self-Navigation Test

This paper proposes a method for the online parameter identification of nonlinear ship motion systems. First, the motion system of a ship is nonlinear, and in the course of sailing, the motion parameters of the ship will change with the change of the motion state of the ship and the sailing environment. To achieve the effect of real-time identification, we adopted an online receding horizon identification method. Second, identification parameters are the essential elements in the navigation control of intelligent merchant ships, and high-precision identification results can achieve better control effects. Therefore, we used an unscented Kalman filter (UKF) that has simpler mathematical structure and higher feedback efficiency than other identification algorithms listed in this paper, such as extended the Kalman filter, Kalman filtering and Ordinary Least Squares, as the identification scheme design algorithm, which is applied to ship motion system identification. Then, to solve the problem of significant identification errors in complex environments, we design a navigation identification framework combining a UKF and rolling wavelet denoising to realize the effect of the online identification of ships. Finally, a Korea Research Institute of Ships and Ocean Engineering (KRISO) Container Ship (KCS) was used for a self-navigation model experiment and data collection. The collected data and identification data were compared and analyzed. By comparing different identification algorithms before and after denoising, it was verified that the UKF algorithm proposed in this paper is superior relative to other traditional algorithms in identifying ship motion systems.

Did Steam Make Shipping Safer? Evidence from the British Coastal Bulk Trades

The transition from sail to steam had more profound effects than any other development in the recorded history of merchant shipping. In combination with iron and steel hulls, steam power enabled ships to become larger, more reliable and more efficient, with far reaching effects on the shipping industry and world trade. But the question has rarely been asked, did the change make ships safer? This was of immediate concern to those working aboard the ships, but also to those who operated, financed, employed and insured them. It might be expected that an iron or steel hull, propelled independently of wind and tide, would be in less danger from accidental loss than a wooden ship largely at the mercy of the elements, but evidence is largely lacking. This paper reports a survey comparing the loss rates of sailing and steam-powered vessels in the British coastal bulk trades, where sail and steam were doing similar work in the same geographical setting. Although steam vessels were marginally safer, the difference in rates of loss are not as great as expected, and reasons for this are discussed, with particular focus on those who worked aboard them or had a financial or commercial interest.

Russia's sanctions policy in the context of the First World War

The article is devoted to the analysis of the sanctions policy of the Russian Empire towards the countries that were its opponents in the First World War. Such states included Germany, Austria-Hungary, Bulgaria, and Turkey, which joined forces in the military bloc of the Central Powers to fight the Allies.&#x0D; The victories of the member states of the Entente bloc were forged not only on the fronts, but also achieved through the partial or complete abolition of trade, financial and economic relations with the countries of the Fourth Bloc. The aim of this paper is to study and comprehend the experience of imposing sanctions by the Russian Empire against states that participated in the war against it during the war of 1914-1918. , which is waging a long-running hybrid war with Ukraine. The article demonstrates an example of an adequate response of state institutions to encroachment on the territorial integrity and sovereignty of the country. It has been proved that immediately after the start of hostilities, measures were taken against the subjects of the states fighting against Russia to limit their legal capacity and legal capacity. They could be deported both outside the country and outside its individual localities.&#x0D; These people were allowed to enter Russia only with the permission of the relevant authorities. Merchant ships of countries fighting against Russia, seized in Russian ports, were detained. Merchant ships built for foreign countries were confiscated and converted for military purposes.&#x0D; Investment policy has also been revised. This is confirmed by the approval by the Russian emperor in 1915 of the Regulations on the Liquidation of Trade Enterprises Belonging to Enemy Citizens, which referred to the liquidation of enterprises and joint-stock companies that co-owned with Russian nationals. It is noteworthy that only those enterprises that operated at the expense of German, Austrian, Hungarian or Turkish investments were subject to liquidation. Other normative legal acts abolished the right of ownership of land of the same group of foreign citizens.&#x0D; The result of the scientific article was the conclusion that by applying the emergency legislation, the Russian government did everything possible to prevent national security from financing the citizens of those countries that were at war with it.

Study of Hybrid Propulsion Systems for Lower Emissions and Fuel Saving on Merchant Ship during Voyage

The hybrid propulsion system is a vehicle propulsion system with two or more sources of propulsion such as diesel, batteries, and other renewable energy. The use of hybrid propulsion systems is not new, and they have been adopted worldwide. There are many applications for hybrid propulsion systems, from powering land-based vehicles to marine vessels. With the success of hybrid propulsion systems, many large vessels still rely on two-stroke engines for power generation. In this paper, the benefits and feasibility of using battery systems or hybridizing existing conventional two-stroke engines onboard large intercontinental vessels is studied and simulated. The merchant ship, a bulk carrier with 82,000 deadweight tonnage capacity, is used. The model vessel travels along a simulated route of up to 4000 nautical miles using weather routing software to generate data for estimating emissions with the help of widely adopted empirical formulas. A reduction of up to 3.4 tonnes of emissions and fuel consumption of not more than 1 tonne per kWh from peak shaving and boosting applications for a 12-day voyage were observed.

Citizen Science Contributions to the Conservation of Sea Turtles Facing Port City and Land Use Stressors in the Mexican Central Pacific

The unplanned development of a port city generates urban growth in its coastal zone that stresses the local biotic and abiotic resources, affecting the nesting beach areas of sea turtles. This work evaluated the impact of social collaboration on sea turtle conservation in response to coastal rigidization. Over the past twenty years, the Manzanillo Port (Colima), located in the Mexican Central Pacific, underwent vigorous development and urbanization. This growth has produced stressors including increasing levels of marine noise pollution due to the transit of merchant ships, the decrease in 4.3 ha in beach areas, and increased light pollution, which likely reduced the number of turtles that reached the nesting stage. Despite the above, the number of turtle nests has increased thanks to social collaboration through protection actions, education programs, and the participation of volunteers along with public and private organizations supported by the media and social networks. These actions are part of citizen science and contribute to the balance between urban development and the protection of sea turtles, reducing environmental vulnerability in the coastal zone. This success story can be reproduced in coastal cities for other wildlife species to achieve a social-ecological benefit through advocacy projects that involve the empowerment of local inhabitants and the appropriation of their landscapes and natural elements. These projects will contribute to alleviating the effects of coastal rigidization in the face of future challenges that will require solutions to different environmental aspects of imminent climate change.

Reliability analysis for the power system of the nuclear ship Savannah

The power system, including the power transmission, distribution, and support system, is one of the largest and most complex systems established by humans. In addition to the normal considerations of power plants on board, the design of nuclear power merchant ships is also based on the need for uninterruptible power supplies. Based on the relevant data of the nuclear power ship “Savannah,” the qualitative and quantitative analysis is performed using the fault tree analysis method to analyze the reliability of its power system. The probability of basic events in certain accident conditions is evaluated according to the literature survey. In addition, this study also examines the common cause failure of diesel generators in the power system, as well as the analysis of sensitivity and importance of basic events. The installation of primary, auxiliary, and emergency power stations, the use of automated equipment for generator synchronization and power conversion, and the application of special internal communication and alarm systems unique to nuclear-powered ships can effectively eliminate the possibility of complete power outages for Savannah.

Optimization of welding application parameters of thin sheet blocks used in the new-generation ship hull

The main material of merchant ships is steel. Generally, block sheets used in forming a ship hull are between 7 and 12 mm. On a 60 m ship, the hull consists of approximately 25–35 mega-blocks and 45–60 blocks. Welding operations cause expansion and shrinkage on the part due to regional temperature differences. The purpose of this study is determining the optimum welding parameter of panels with 48 × 1200 cm dimensions and 5 mm thickness. Because the thickness of the sheet metal used is very thin, the blocks to be welded are very large and the mega-blocks formed by welding are used in large numbers and include uncertainties such as optimal parameters in the process application and mechanical behavior on the weld. To reduce the number of experiments within the scope of the study, welding application conditions were determined by using Taguchi experimental design (L9). In the determined parameters, submerged arc welding was carried out on the panels in a horizontal position. Taking 10 × 48 cm sections as head–middle–end from each combined panel, visual control and radiographic testing (ISO 5580) was performed. Tensile (TS EN ISO 4136) and notch-impact (TS EN ISO 9016) mechanical tests were also conducted. By conducting statistical analysis (analysis of variance) of the selected parameters used in the Taguchi experimental design, percentage effects of each parameter on yield strength, tensile strength and notch-impact tests were obtained. The impact percentage of the highest current was determined; the results were 50.24% for yield strength, 51.43% for tensile strength and 57.53% for notched-impact test results. Data means were checked with design of experiment analysis. The best welding results were obtained at parameters of 650 A, 32 V and 150 cm/min.

Unerroric Automatic Control of Civil Hydroacousticer’s Working Quality on Board

The collision of a dry cargo ship with a submarine off Cape Ashizuri this year has actualized the study of the possibility of unerroric control of readiness of passenger and merchant ships to extreme variants of hydroacoustic conditions. The purpose of the research is to develop digital methods and algorithms of automatic quality control of ship’s hydroacousticer. The possibility of such control by multilevel estimation of results within training hydroacousticer on board of the ship is investigated. Recurrent methods and algorithms of formation of final and intermediate estimations of results of such training in a training mode within functioning of on board hydroacoustic means are offered and developed. These methods and algorithms allow complicating the simulation model of hydroacoustic environment fraught with ship accidents.

Implications of autonomous shipping for maritime education and training: the cadet’s perspective

The Industrial Revolution 4.0 has not left the transportation sector behind. All modes of transportation have, to some extent, already been affected, and maritime is the last to join them. Currently available technology makes autonomous merchant ships a possible alternative to conventional, manned vessels with seafarers. This upcoming shift requires the preparation of necessary policies, such as rethinking obsolete training curricula, in relation to a variety of aspects of the industry, including the future of seafaring as a profession. To formulate such policies, the views of professional seafarers and scholars are sometimes solicited, but the opinions of industry entrants are often neglected. However, the latter may also have some interesting views on the future of their profession, which may be relevant to policy-makers. The results of a worldwide survey, conducted using the Computer-Assisted Web Interviewing (CAWI) method, suggest that the future generation of seafarers fears automation less than their mentors. Although they expect their skills to be useful in automation-driven shipping, they also feel that their Maritime Education and Training institutions (MET) are not doing enough to prepare them for the challenges that the future may hold. This may be due to a lack or poor coverage of shipping autonomization issues in MET curricula, which was mentioned by as many as 41.9% of the respondents. This finding advocates for rethinking the curricula of METs and human resources management in the shipping industry of the future.

Merchant networks in big cities

In the 18th century, every second merchant ship sailing from Britain to the Baltic did not carry any exports. This was caused by trade imbalances that were driven by high demand for grains and other raw materials in Britain. Trip level data show that merchant ships based in larger British cities were more likely to make non-empty trips and carried more varieties. This paper argues that wider and denser networks of merchants in large cities, which facilitated information flows and improved the efficiency of matching, allowed them to outperform merchants from smaller British ports. Furthermore, ships that were based in smaller ports did not improve their performance when they departed from larger cities. This finding and additional tests provide evidence against competing explanations.

Merchant Shipping during Global Health Pandemics: A Review of International Regulations

Abstract This article examines the impact of COVID-19 on the international regulation of merchant shipping. First, it provides an overview of the international regulatory framework established by the WHO, IMO and ILO to respond to the impact of global health emergencies on international merchant shipping. It then examines the responses of these organisations and the shipping industry to the impact of the COVID-19 pandemic on merchant shipping. The COVID-19 pandemic has demonstrated that global health emergencies require enhanced preparedness and response planning and cooperation between the IMO, WHO and ILO, which includes consultation and cooperation with global shipping associations and seafarers’ unions. The objective of the preparedness and response planning should be to keep maritime supply chains open while preventing the spread of infectious disease from ship-to-ship, ship-to-shore or shore-to-ship. Equally important, the enhanced cooperation at the global level must be matched by enhanced inter-agency cooperation at the national level.