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This paper presents the "Three Gorges Hydrogen Boat No. 1", a novel green hydrogen-powered vessel that has been successfully delivered and is currently sailing. This vessel, integrated with a hydrogen production and bunkering station at its dedicated dock, achieves zero-carbon emissions. It stores 240 kg of 35 MPa gaseous hydrogen and has a fuel cell system rated at 500 kW. We analysed the engineering details of the marine hydrogen system, including hydrogen bunkering, storage, supply, fuel cell, and the hybrid power system with lithium-ion batteries. In the first bunkering trial, the vessel was safely refuelled with 200 kg of gaseous hydrogen in 156 min via a bunkering station 13 m above the water surface. The maximum hydrogen pressure and temperature recorded during bunkering were 35.05 MPa and 39.04 °C, respectively, demonstrating safe and reliable shore-to-ship bunkering. For the sea trial, the marine hydrogen system operated successfully during a 3-h voyage, achieving a maximum speed of 28.15 km/h (15.2 knots) at rated propulsion power. The vessel exhibited minimal noise and vibration, and its dynamic response met load change requirements. To prevent rapid load changes to the fuel cells, 68 s were used to reach 483 kW from startup, and 62 s from 480 kW to zero. The successful bunkering and operation of this hydrogen-powered vessel demonstrates the feasibility of zero-carbon emission maritime transport. However, four lessons were identified concerning bunkering speed, hydrogen cylinder leakage, hydrogen pressure regulator malfunctions, and fuel cell room space. The novelty of this work lies in the practical demonstration of a fully operational, hydrogen-powered maritime vessel achieving zero emissions, encompassing its design, building, operation, and lessons learned. These parameters and findings can be used as a baseline for further engineering research. [Display omitted] • Configuration of a zero-carbon emission vessel using green hydrogen fuel. • Engineering details of a 500 kW marine hydrogen and PEMFC system. • Hydrogen bunkering process, pressure, and temperature management. • Performance of a hydrogen-powered vessel during sailing. • Lessons learned from the design and construction of a marine hydrogen system. [ABSTRACT FROM AUTHOR]

Large container ships are the main means of maritime trade transportation, and transportation safety and efficiency directly affect global economic development. The complex maritime navigation conditions make it difficult to ensure the safety and efficiency of large container ships. In order to improve the safety and transportation efficiency of large container ships sailing at sea, a Maneuvering Motion Generator (MMG) is proposed. Based on the existing four degree of freedom model, a six degree of freedom ship maneuvering motion model is constructed to simulate and analyze the sea maneuvering of large container ships. The results showed that the constructed model accurately simulated the changes in pitch angle and roll angle during ship navigation, and the error between roll angle and pitch angle did not exceed 0.2°. When the relative wind direction was 120°, and the wind speed was 13m/s, wind interference had the greatest impact on ship navigation. At this time, the lateral deviation was more than 120m, and the heading deviation angle was more than 4°. When the wind speed was 16m/s, the influence of wind interference on the ship's heading was significantly reduced after the ship's steering, and the deviation angle reduced from 0.3° to almost no effect. The designed simulation model for large ship maneuvering compensates for the lack of upper and lower wave states in ship maneuvering simulation, accurately simulating the sea motion state of large ships. This result helps operators make optimal decisions in strong winds and other disruptive environments, improving the safety and efficiency of large ships navigating at sea. [ABSTRACT FROM AUTHOR]

Iron and its numerous alloys are one of the essential needs of today's mankind, whose supply and demand must be properly managed. Destruction and recycling of end-of-life ships is one of the important sources of steel supply for other industries, which requires new management and legal methods due to the human and environmental hazards during the dismantling of this extremely large structure. In this research; considering the management challenges and legal restrictions, while justifying the need for ship recycling, using the library research method, considering the situation of steel industries in the persian gulf countries and using the production statistics of steel industries, the need for ship recycling and economic value added should be explained. The ship recycling industry, as it is done in countries like Bangladesh, India and Pakistan, is dangerous and pollutes the coastal and sea environment; but according to the current situation and the country's need to establish this industry, its development is conditional on providing environmental standards. Such a thing seems necessary considering the way it is being done in the border country of the Persian Gulf and the Oman Sea, i.e., the United Arab Emirates, due to the similarity of the climate with the south of the country. [ABSTRACT FROM AUTHOR]

The objective of this study is to perform a thermodynamic analysis on a marine diesel engine waste heat-assisted cogeneration power plant modified with regeneration onboard a ship. The proposed system utilizes the waste heat from the main engine jacket water and exhaust gases to generate electricity and heat, thereby reducing the fuel consumption and CO2 emissions. The methodology includes varying different turbine inlet pressures, extraction pressures, and fractions of steam extracted from the turbine to evaluate their effects on the efficiency, utilization factor, transformation energy equivalent factor, process heat rate, electrical power output, saved fuel flow rate, saved fuel cost, and reduced CO2 emissions. The analysis demonstrates that the proposed system can achieve an efficiency of 48.18% and utilization factor of 86.36%, savings of up to 57.325 kg/h in fuel, 65.606 USD/h in fuel costs, and 180.576 kg/h in CO2 emissions per unit mass flow rate through a steam turbine onboard a ship. [ABSTRACT FROM AUTHOR]

Day after day, stricter environmental regulations and rising operating costs and fuel prices are forcing the shipping industry to find more effective ways of designing and operating energy-efficient ships. One of the ways to produce electricity efficiently is to create a waste heat-driven liquid metal–water binary vapor power plant. The liquid metal Rankine cycle systems could be considered topping cycles. Liquid metal binary cycles share characteristics like those of the steam Rankine power plants. They have the potential for high conversion efficiency, they will likely produce lower-cost power in plants of large capacity rather than small, and they will operate more efficiently at design capacity rather than at partial load. As a result, liquid metal topping cycles may find application primarily as base-load plants onboard ships. In this study, a waste heat-driven liquid metal–water binary vapor power plant onboard a ship is designed and thermodynamically analyzed. The waste heat onboard the vessel is the exhaust gas of the LM2500 marine gas turbine. Mercury and Cesium are selected as liquid metals in the topping cycle, while water is used in the bottoming cycle in binary power plants. Engineering Equation Solver (EES) software (V11.898) is used to perform analyses. For the turbine inlet temperature of 550 °C, while the total net work output of the binary cycle system is calculated to be 104.84 kJ/kg liquid metal and 1740.29 kJ/kg liquid metal for mercury and cesium, respectively, the efficiency of the binary cycle system is calculated to be 31.9% and 26.3% for mercury and cesium as liquid metal, respectively. This study shows that the binary cycle has a thermal efficiency of 26.32% and 31.91% for cesium and mercury, respectively, depending on liquid metal condensing pressure, and a binary cycle thermal efficiency of 25.9% and 30.9% for cesium and mercury, respectively, depending on liquid metal turbine inlet temperature, and these are possible with marine engine waste heat-driven liquid metal–water binary vapor cycles. [ABSTRACT FROM AUTHOR]

Taking the large-size shipbuilding block as the research object, this article describes the general phenomenon of the long blasting operation time and long painting operation time, and analyzes its impact and reasons. Through a series of refined management practices such as fine production preparation, strengthened process control and improved equipment efficiency, a new process of "block blasting completion in the morning" is put forward to achieve good results such as production efficiency improvement and cost reduction as well as social benefits. [ABSTRACT FROM AUTHOR]

Copyright of Computer Measurement & Control is the property of Magazine Agency of Computer Measurement & Control and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: The clavicle remains one of the most fractured bones in the human body, despite the fact that little is known about the MR imaging of it and the adjacent sternoclavicular joint. This study aims to establish standardized values for the diameters of the clavicle as well as the angles of the sternoclavicular joint using whole-body MRI scans of a large and healthy population and to examine further possible correlations between diameters and angles and influencing factors like BMI, weight, height, sex, and age. Methods: This study reviewed whole-body MRI scans from the Study of Health in Pomerania (SHIP), a German population-based cross-sectional study in Mecklenburg–Western Pomerania. Descriptive statistics, as well as median-based regression models, were used to evaluate the results. Results: We could establish reference values based on a shoulder-healthy population for each clavicle parameter. Substantial differences were found for sex. Small impacts were found for height, weight, and BMI. Less to no impact was found for age. Conclusions: This study provides valuable reference values for clavicle and sternoclavicular joint-related parameters and shows the effects of epidemiological features, laying the groundwork for future studies. Further research is mandatory to determine the clinical implications of these findings. [ABSTRACT FROM AUTHOR]

Maritime transportation plays a crucial role in global trade, as evidenced by the vast amount of containerized cargo transported between ports. In the realm of containerized maritime transport, an increasingly critical challenge lies in the efficient assignment of berths. Effectively organizing operations at small ports is a fundamental element in establishing a more streamlined and dependable overall maritime supply chain, ultimately benefiting larger ports. In this paper, we address the berth allocation problem at small ports and use a mathematical model; aiming to minimize the service time of all ships at the port and thereby reducing fuel consumption and emissions. To achieve this, we employed two meta-heuristics; genetic algorithm and tabu search. Results were further optimized using a criterion for the best scheduling of ships, demonstrating their significance through comparison with the FCFS method applied at the port of Annaba in Algeria.

Firefighting training using virtual reality (VR) technology has still not been used extensively in the maritime industry. One of the reasons lies in the inability of VR to accurately replicate the true dynamics of a fire. However, this shortfall can be effectively addressed by integrating computational fluid dynamics-based (CFD) models of fire spread into VR training simulations, thereby significantly enhancing the realism and educational value of these scenarios. In this study, a scenario of a fire spread inside the ship engine room has been developed. First, as a CFD analysis, whose results were then transferred to the VR environment. That approach has been tested with users who have noted that CFD-based fire gives a more realistic appearance than the generic modelled solely using the game engine.

Since the slamming load could cause severe damage of wet deck of ship hull girder, the interaction between the structural response and hydrodynamic loading should be considered. A large scaled model of trimaran was designed, which could consider the structural elastic for studying the structural response of trimaran hull girder. The testing model was vertically dropped into still water in the tank to simulate typical hydroelastic slamming load, in which various impact velocities were considered. Each load condition was conducted several times to verify the repeatability and reproducibility of the experimental data. The slamming pressure and strain distributions are presented and discussed. The ranges of maximum slamming pressure and the danger area are identified for design of this type of trimaran. [ABSTRACT FROM AUTHOR]

The article focuses on the observation of Grey-faced Buzzards landing on a ship during their spring migration, a behavior not previously documented in this species or other raptors. Topics include the challenges of migrating over water bodies, the ecological and migratory patterns of Grey-faced Buzzards, and the details of the observed behavior and its potential significance for understanding migration strategies.

In recent years, China's shipbuilding industry has developed rapidly, and many large shipbuilding enterprises have applied innovative methods in the research and construction process. Six Sigma is one of the commonly used methods. Through an overview and analysis of the Six Sigma method, this paper summarizes the typical applications of this innovative method in the field of shipbuilding, points out the main problems in current industrial applications, such as the low use of a single innovative method and the few integrated applications of multiple innovative methods, establishes the innovation integration framework of innovative methods such as Six Sigma in the field of shipbuilding, and prospects the continuous and in-depth application of innovative methods in the ship field. [ABSTRACT FROM AUTHOR]

Trim optimization is an available approach for the energy saving and emission reduction of a ship. As a ship sails on the water, the draft and trim undergo constant changes due to the consumption of fuel oil and other consumables. As a result, the selection of the initial trim is important if ballasting or shifting liquid among the tanks is not considered during a voyage. According to the characteristics of ship navigation and maneuvering, a practical trim optimization method is proposed to identify the Optimal Trim over a Whole Voyage (OTWV) which makes the fuel consumption of the voyage minimum. The calculations of speed vs. draft and trim surfaces are created according to hull resistance data generated by CFD, model tests, or real ship measurements, and these surfaces are used to calculate the OTWV. Ultimately, a trim and Main Engine (ME) power joint optimization method is developed based on the OTWV to make the total fuel consumption minimum for a voyage with a fixed length and travel time. A 307000 DWT VLCC is taken as an example to validate the practicality and effect of the two proposed optimization methods. The trim optimization example indicates that the OTWV could save up to 1.2% of the total fuel consumption compared to the Optimal Trim at Initial Draft (OTID). The trim and ME power joint optimization results show that the proposed method could steadily find the optimal trim and ME power combination, and the OTWV could save up to 1.0% fuel consumption compared to the OTID in this case. [ABSTRACT FROM AUTHOR]

With the development of bridge crossings over rivers, the accident of the vessel–bridge collision is increasing as well. It is important to assess probability of bridges colliding with passing ships. Firstly, the AIS (Automatic identify system) data was collected and decoded to obtain the dynamic information of the ships passing the bridge including the distributions of ships position, speed, and yaw angle, which are then compared with the value recommended by the AASHTO (American Association of State Highway and Transportation Officials) specification. The mainly influential parameters of ship–bridge collision obtained from AIS data are used to correct the variables in the risk assessment of AASHTO specification, which intends to improve the assessment accuracy by considering the actual information of passing vessels. The collision probability with and without considering the actual situations of passing ships are compared. It is found that the distribution and transit path of passing ships significantly influence the collision probability. To improve the risk assessment accuracy, it is suggested to use the actual distributions of passing ships from AIS data. [ABSTRACT FROM AUTHOR]

The industry is currently responsible for around 21% of the total CO2 emissions, mainly due to heat production with fossil fuel burners. There are already different technologies on the market that can potentially reduce CO2 emissions. Nevertheless, the first step for their introduction is to analyze their potential on a global scale by detecting in which countries each of them is more attractive, given their energy prices and resources. The present work involves a techno-economic analysis of different alternatives to replace industrial gas boilers for low-pressure steam production at 120 °C and 150 °C. Solar Heat for Industrial Processes (SHIP) was compared with Electric Boilers (EBs), High-Temperature Heat Pumps (HTHPs), and Absorption Heat Transformers (AHTs). SHIP systems have the potential to reach payback periods in the range of 4 to 5 years in countries with Direct Normal Irradiance (DNI) values above 1400 kWh/m2/year, which is reached in Spain, Italy, Greece, Portugal, and Romania. HTHPs and AHTs lead to the lowest payback periods, Levelized Cost of Heat (LCOH), and highest CO2 emission savings. For both AHTs and HTHPs, payback periods of below 1.5 years can be reached, particularly in countries with electricity-to-gas price ratios below 2.0. [ABSTRACT FROM AUTHOR]

The dolphin motif on the ship-shaped oil lamp treasured in the Museum of Smederevo (4th century AD) has complex iconography, multi-layered and complex symbolism, and a long history. This article presents and explains how its iconography and meaning were gradually formed and developed in ancient Greek and Roman art, as well as the peculiarities of its gradual transformation into a Christian symbol. It is found that the context of the appearance of the dolphin motif in art during different epochs is not a mere coincidence, but the expression of a clear intention on the part of particularly learned artists and commissioners of works of art. Since there are no written records of this motif that would explain its iconography and meaning, and since the motif itself is by nature very hermetic, and at the same time very rare, the characteristic context of the appearance of the dolphin motif in art is also a decisive parameter for analyzing its meaning and its gradual formation.

Ballast water management is an effective measure to ensure that organisms, bacteria and viruses do not migrate with the ballast water to other areas. In 2004, the International Maritime Organization adopted the International Convention on the Control and Management of Ballast Water and Ship Sediments, which regulates issues related to ballast water management. Many technologies have been researched and developed, and of these, the use of UV rays in combination with filter membranes has been shown to have many advantages and to meet the requirements of the Convention. However, the use of UV furnaces in ballast water treatment systems requires a very large capacity, involving the use of many high-power UV lamps. This not only consumes large amounts of electrical energy, but is also expensive. It is therefore necessary to find an optimal algorithm to enable the UV radiation for the UV controller in the ballast water sterilisation process to be controlled in a reasonable and effective manner. This controller helps to prolong the life of the UV lamp, reduce power consumption and ensure effective sterilisation. This paper presents a UV control algorithm and a controller for a UV furnace for a ballast water treatment system installed on a ship. The results of tests on vessels illustrate the effect of the proposed UV controller.

The functional layout of fire safety equipment in technical spaces of ships is a time-consuming process. When designing a ship fire protection system, the designer must manually position each system component in such a way as to meet the requirements of regulations arising from the technical specification, various legal regulations of maritime conventions and classification societies of the vessel to be designed. Layout of fire hydrants assisted by a computer that is based on pre-defined criteria and various constraints could significantly support the designer in working easier and faster. This paper presents a prototype computer-aided design system that enables optimal placement of fire hydrants using the metaheuristic Particle Swarm Optimization (PSO) algorithm. This algorithm was used in Rhinoceros 3D software with its Grasshopper plugin for visualizing the arrangement of fire safety equipment. Various solution arrangements compared with the fire hydrant placement in real ships are illustrated by a case study. Demonstrating how design work can be facilitated and what potential benefits can be achieved are presented as well.

The objective of this study is to perform a thermodynamic analysis on a marine diesel engine waste heat-assisted cogeneration power plant modified with regeneration onboard a ship. The proposed system utilizes the waste heat from the main engine jacket water and exhaust gases to generate electricity and heat, thereby reducing the fuel consumption and CO2 emissions. The methodology includes varying different turbine inlet pressures, extraction pressures, and fractions of steam extracted from the turbine to evaluate their effects on the efficiency, utilization factor, transformation energy equivalent factor, process heat rate, electrical power output, saved fuel flow rate, saved fuel cost, and reduced CO2 emissions. The analysis demonstrates that the proposed system can achieve an efficiency of 48.18% and utilization factor of 86.36%, savings of up to 57.325 kg/h in fuel, 65.606 USD/h in fuel costs, and 180.576 kg/h in CO2 emissions per unit mass flow rate through a steam turbine onboard a ship.

Non-photochemical quenching (NPQ) within phytoplankton cells often causes the daytime suppression of chlorophyll fluorescence in the Southern Ocean. This is problematic and requires accurate correction when chlorophyll fluorescence is used as a proxy for chlorophyll-a concentration or phytoplankton abundance. In this study, we reveal that Southern Ocean subsurface chlorophyll maxima (SCMs) are the largest source of uncertainty when correcting for NPQ of chlorophyll fluorescence profiles. A detailed assessment of NPQ correction methods supports this claim by taking advantage of coincident chlorophyll fluorescence and chlorophyll concentration profiles. The best performing NPQ correction methods are conditional methods that consider the mixed layer depth (MLD), subsurface fluorescence maximum (SFM) and depth of 20% surface light. Compared to existing methods, the conditional methods proposed halve the bias in corrected chlorophyll fluorescence profiles and improve the success of replicating a SFM relative to chlorophyll concentration profiles. Of existing methods, the X12 and P18 methods, perform best overall, even when considering methods supplemented by beam attenuation or backscatter data. The widely-used S08 method, is more varied in its performance between profiles and its application introduced on average up to 2% more surface bias. Despite the significant improvement of the conditional method, it still underperformed in the presence of an SCM due to 1) changes in optical properties at the SCM and 2) large gradients of chlorophyll fluorescence across the pycnocline. Additionally, we highlight that conditional methods are best applied when uncertainty in chlorophyll fluorescence yields is within 50%. This highlights the need to better characterize the bio-optics of SCMs and chlorophyll fluorescence yields in the Southern Ocean, so that chlorophyll fluorescence data can be accurately converted to chlorophyll concentration in the absence of in situ water sampling. [ABSTRACT FROM AUTHOR]

In order to realize the intelligent energy management of the complex ship energy system, achieve the carbon peaking and carbon neutrality goal and reduce the ship carbon emissions and ship operating costs, this paper proposes a distributed energy management method for ships entering and leaving ports based on polymorphic network considering computing power resources. Firstly, a polymorphic network-based energy management system for ships entering and leaving ports is proposed to enhance the information exchange between ship computing power, power and port power, simultaneously improve the communication quality and communication security among different modes. Secondly, in order to reduce the ship operating costs and port carbon emissions, the energy management model of ships entering and leaving ports is constructed considering computing power resources. Then, according to the ship's berthing and departing operation modes, this paper uses the distributed algorithm to solve the energy management problem, and explores the impact on the ship microgrid when the ship's data load changes. Finally, simulation results verify the effectiveness of the proposed algorithm. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Applied Mechanics is the property of Chinese Journal of Applied Mechanics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To comply with the International Maritime Organization's sulfur regulations, shipping companies have mainly favored scrubber systems. Even though the ship's operations might be continued provided regulatory constraints are followed, the installation presents system-based risks depending on the scrubber type. This study's primary aim is to inform the shipping industry about the risks associated with various scrubber applications on ships and to propose guidelines to ensure safer scrubber operation on marine vessels. Consequently, a risk evaluation is conducted on all kinds of scrubber systems. Experts in the marine industry identify the main subsystems and components and evaluate their failure modes and consequences. Using the fuzzy failure modes and effects analysis method, the acquired judgments are analyzed. The risk value of each failure scenario is computed using the Mamdani fuzzy inference technique and the evaluation of expert ratings. The riskiest failure modes identified by the investigation include the sensing element, injection nozzles, packed peds, and seawater system valves. [ABSTRACT FROM AUTHOR]

Copyright of Computer Measurement & Control is the property of Magazine Agency of Computer Measurement & Control and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The transportation of dangerous aquatic organisms and pathogens in ballast tanks causes problems on a global scale and therefore, The International Maritime Organization (IMO) has put into force the "International Convention for the Control and Management of Ships' Ballast Waters and Sediments". There are many ballast water treatment systems (BWTS) available in the market. The most important issue in the integration of the systems to the ships is to have technical information about the available options and to determine the most suitable solution for the ship among these alternatives. For this, the interested parties need to make an appropriate choice by knowing the features, advantages, and disadvantages of the BWTSs. The main aim of this article is to assess the five types of BWTS technologies that are frequently used and to make an optimum choice by consulting the opinions of experts in the sector. In this context, this study used the fuzzy ELECTRE (ELimination Et Choix Traduisant la REalite') method and proposed a novel approach for handling BWTS selection based upon interval type-2 fuzzy sets. It has been evaluated that a hybrid system in which filtration + ultrasound + ultraviolet (UV) systems can be used together would be more appropriate. [ABSTRACT FROM AUTHOR]

In this research, E2YOLOX-VFL is proposed as a novel approach to address the challenges of optical image multi-scale ship detection and recognition in complex maritime and land backgrounds. Firstly, the typical anchor-free network YOLOX is utilized as the baseline network for ship detection. Secondly, the Efficient Channel Attention module is incorporated into the YOLOX Backbone network to enhance the model's capability to extract information from objects of different scales, such as large, medium, and small, thus improving ship detection performance in complex backgrounds. Thirdly, we propose the Efficient Force-IoU (EFIoU) Loss function as a replacement for the Intersection over Union (IoU) Loss, addressing the issue whereby IoU Loss only considers the intersection and union between the ground truth boxes and the predicted boxes, without taking into account the size and position of targets. This also considers the disadvantageous effects of low-quality samples, resulting in inaccuracies in measuring target similarity, and improves the regression performance of the algorithm. Fourthly, the confidence loss function is improved. Specifically, Varifocal Loss is employed instead of CE Loss, effectively handling the positive and negative sample imbalance, challenging samples, and class imbalance, enhancing the overall detection performance of the model. Then, we propose Balanced Gaussian NMS (BG-NMS) to solve the problem of missed detection caused by the occlusion of dense targets. Finally, the E2YOLOX-VFL algorithm is tested on the HRSC2016 dataset, achieving a 9.28% improvement in mAP compared to the baseline YOLOX algorithm. Moreover, the detection performance using BG-NMS is also analyzed, and the experimental results validate the effectiveness of the E2YOLOX-VFL algorithm. [ABSTRACT FROM AUTHOR]

The current study is focused on the analysis of methods and means for reducing marine engine exhaust and greenhouse gases (GHGs). The research method consists in identifying equipments that have been applied in the case of small four-stroke marine engines used as emergency generators on board large ships, specifically the Cummins Qsb6.7-G16 model. The results, which were demonstrated by practical experiences of the different possible configurations for the engine studied showed high potential for reducing emissions, but the most suitable alternative is the Selective Catalytic Reduction (SCR). [ABSTRACT FROM AUTHOR]

Copyright of Revista de Relaciones Internacionales, Estrategia y Seguridad is the property of Revista de Relaciones Internacionales, Estrategia y Seguridad and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Using evidence of wood-borers in several of the National Museum of the Royal Navy's historic ships, this article will examine the threat posed to the historic fabric by non-marine species and the reasons that we struggle to eradicate the problem. The relationship between fungal attack and beetle activity will be discussed, and the need for supporting research into this and other aspects of damage due to wood-boring species. HMS Victory, HMS Warrior and HMS Trincomalee all suffer from attack by wood-boring species, though the infestations are in different stages of development on each vessel. By investigating and employing an integrated pest management strategy on Trincomalee, we hope to learn more about the most effective means of combatting the much more widespread infestation of death watch beetle on Victory. Other wood-borers including weevil, furniture beetle and wharfborer are also present across our collection of ships, and all these species are facilitated by the damp conditions which can never be truly resolved as the ships are located in open coastal environments. [ABSTRACT FROM AUTHOR]

This study aims to (1) find out how to implement the safety management system on board ships at shipping companies in Banjarmasin 2) to know the safety management system on board. This, of course, related to occupational health and safety, is a thought and effort to ensure the integrity and perfection of both physical or spiritual with efforts to prevent and treat diseases or health problems caused by work and the work environment, as well as general illnesses. Occupational safety is a series of efforts to create a safe and peaceful working atmosphere for employees who work in the company concerned and a condition that is safe and safe from suffering and damage or loss in the workplace, both when using tools, materials, machines in the process processing, packing techniques, storage, as well as maintaining and securing the workplace and environment. [ABSTRACT FROM AUTHOR]

In 2016, an American autonomous underwater glider was seized by the Chinese navy in the South China Sea. The United States considered this a hostile act as the glider was sovereign immune. The Chinese maintained they were merely detaining an unknown craft to properly identify it. The glider was subsequently returned to the United States. Despite this incident ending somewhat peacefully, the issues that led to and stem from it are far from resolved. Was China right in detaining an unidentified object? Or was the United States right asserting that all craft are covered by sovereign immunity if so declared? Can autonomous vessels even have sovereign immunity? These issues are symptomatic of the technological age and the struggle of law to keep pace with constant advancements: new types of vessels do not fit neatly into the definitions of current international law, putting them in regulatory limbo. If not addressed, this could lead to an escalated incident in the future. This article considers the challenges of classifying autonomous vessels under international law, the function of sovereign immunity at sea, and whether it can apply to autonomous vessels. It will also consider potential methods for clarifying the issue at law. [ABSTRACT FROM AUTHOR]

Copyright of Metal Working (1674-165X) is the property of Metal Working Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Modern ships are complex energy systems containing a large number of different elements. Each of these elements is simulated separately. Since all these models form a single system (ship), they are interdependent. The operating modes of some systems influence others, but at the same time, the work of all the systems should be aimed at fulfilling the basic functions of the ship. The work proposes a methodological approach to combining various systems of ships into a single complex model. This model allows combining models of ship systems of various levels (microlevel, macrolevel, metalevel, megalevel). The work provides examples of models of such multi-level energy systems. These are energy systems composed of an electric generator, a diesel engine, a propeller shaft, and algorithms used for operating the common parts of the ship's electric power system and a piston wear process. Analytical, structural, numerical, and object-oriented models were made for these objects. Each of these particular models describes a limited class of problems, has characteristic properties, and a mathematical structure. The work shows how particular models can be interconnected using a set-theoretic description. Particular models are combined into macrolevel models, whose output parameters are quantities that are by no means related. The macrolevel models are interrelated using control models. Control models belong to the metalevel and allow for assigning settings and response thresholds to algorithms used in automation systems. Such a model (megalevel model) allows, ultimately, investigating the dynamics of the entire system as a whole and managing it. [ABSTRACT FROM AUTHOR]

The existing image matching methods for remote sensing scenes are usually based on local features. The most common local features like SIFT can be used to extract point features. However, this kind of methods may extract too many keypoints on the background, resulting in low attention to the main object in a single image, increasing resource consumption and limiting their performance. To address this issue, we propose a method that could be implemented well on resource-limited satellites for remote sensing images ship matching by leveraging line features. A keypoint extraction strategy called line feature based keypoint detection (LFKD) is designed using line features to choose and filter keypoints. It can strengthen the features at corners and edges of objects and also can significantly reduce the number of keypoints that cause false matches. We also present an end-to-end matching process dependent on a new crop patching function, which helps to reduce complexity. The matching accuracy achieved by the proposed method reaches 0.972 with only 313 M memory and 138 ms testing time. Compared to the state-of-the-art methods in remote sensing scenes in extensive experiments, our keypoint extraction method can be combined with all existing CNN models that can obtain descriptors, and also improve the matching accuracy. The results show that our method can achieve ∼50% test speed boost and ∼30% memory saving in our created dataset and public datasets. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the incidence, diagnostic management strategies and clinical outcomes of women with spontaneous haemoperitoneum in pregnancy (SHiP) and reassess the definition of SHiP. Design: A population‐based cohort study using the Netherlands Obstetric Surveillance System (NethOSS). Setting: Nationwide, the Netherlands. Population: All pregnant women between April 2016 and April 2018. Methods: This is a case study of SHiP using the monthly registry reports of NethOSS. Complete anonymised case files were obtained. A newly introduced online Delphi audit system (DAS) was used to evaluate each case, to make recommendations on improving the management of SHiP and to propose a new definition of SHiP. Main outcome measures: Incidence and outcomes, lessons learned about clinical management and the critical appraisal of the current definition of SHiP. Results: In total, 24 cases were reported. After a Delphi procedure, 14 cases were classified as SHiP. The nationwide incidence was 4.9 per 100 000 births. Endometriosis and conceiving after artificial reproductive techniques were identified as risk factors. No maternal and three perinatal deaths occurred. Based on the DAS, adequate imaging of free intra‐abdominal fluid, and identifying and treating women with signs of hypovolemic shock could improve the early detection and management of SHiP. A revised definition of SHiP was proposed, excluding the need for surgical or radiological intervention. Conclusions: SHiP is a rare and easily misdiagnosed condition that is associated with high perinatal mortality. To improve care, better awareness among healthcare workers is needed. The DAS is a sufficient tool to audit maternal morbidity and mortality. [ABSTRACT FROM AUTHOR]

A proposed solution is presented to address the issue of rising energy loss resulting from inaccurate power prediction in the predictive energy management strategy for composite electric power electric ship. The solution involves the development of a power prediction model that integrates Archimedes' algorithm, optimized variational modal decomposition, and BiLSTM. Within the framework of Model Predictive Control, this predictive model is utilized for power forecasting, transforming the global optimization problem into one of optimizing the power output distribution among power sources within the predictive time domain, then the optimization objective is to minimize the energy loss of the composite electric power system, and a dynamic programming algorithm is employed to solve the optimization problem within the forecast time domain. The simulation findings demonstrate a significant enhancement in the forecast accuracy of the power prediction model introduced in this study, with a 52.61% improvement compared to the AOA-BiLSTM power prediction model. Concurrently, the energy management strategy utilizing the prediction model proposed in this research shows a 1.02% reduction in energy loss compared to the prediction model control strategy based on AOA-BiLSTM, and a 15.8% reduction in energy loss compared to the ruler-based strategy.

Cathodic protection utilizing sacrificial anodes is an effective method to prevent marine ships and marine engineering structures from corrosion in seawater. The establishment and improvement of relevant standards are of great significance for controlling product quality, promoting the advancement of cathodic protection technology, and facilitating the application of new technologies and products. In this paper, the main domestic and international standards for sacrificial anode materials used in ships and marine engineering were introduced. Additionally, a comparative analysis was conducted on the sacrificial anode inspection standards from perspective of the physical performance, chemical compositions, and electrochemical properties of the sacrificial anodes. On this basis, suggestions for improving and applying the standards were proposed.

It is an important way to study the ship wake by building simulation data through the acoustic wake echo signal model. At present, the scattering echo of a single bubble is ignored in the existing models. Therefore, a point scattering model for different regions was proposed in this paper. Firstly, the wake geometry model was determined according to the ship size, speed, and sea condition, and then the wake was divided into different scattering regions according to the bubble size distribution(BSD). The range of the wake homing system was determined according to the beam width, position, and launch angle of the transmitting and receiving platform. Finally, the range of the wake homing system was divided into finite scattering elements, and the scattering echo signal was calculated according to the point scattering model after considering the propagation loss. The results of simulation and water tank experiments show that the model can be used in ship wake simulation and provide support for further wake detection and identification.