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Zero-emission ships (ZESs) have gained interest to comply with the stringent regulations of international maritime organization. One way to build ZES is the hybridization of fuel cells with batteries. Traditionally, for a newly built ship, the energy and emissions management system (EEMS) is designed based on the initial condition of the fuel cells and batteries and used with fixed parameters in future execution. However, for a fuel cell and battery ZES, the EEMS gradually becomes suboptimal since the characteristics of fuel cells and batteries are continuously changing due to aging and degradation. In this article, a reinforcement learning (RL)-based EEMS is developed such that it can learn and adapt continuously to changes in the fuel cell/battery characteristics. Within RL, different types of algorithms, such as double deep $Q$-learning (DDQL), soft actor–critic (SAC), and proximal policy optimization (PPO) are implemented. The results are benchmarked against those of a typical rule-based EEMS. Each RL algorithm is trained with four reward function formulations; negative cost ($r_{1}$), negative quadratic cost ($r_{2}$), inverse cost ($r_{3}$), and inverse quadratic cost ($r_{4}$). The results demonstrate that health-aware EEMS can minimize fuel consumption and component degradation costs. $r_{1}$ has led to the lowest operational expenses (OPEX) followed by $r_{2}$, while $r_{3}$ and $r_{4}$ have high OPEX. Among the three algorithms, the DDQL led to the lowest reward followed by the SAC and then the PPO, when trained with $r_{1}$ and $r_{2}$.

This work evaluates the use of potassium hydroxide (KOH) and potassium oxalate monohydrate (K2C2O4·H2O) for the formation of nitrogen- and oxygen-doped porous carbons. On the basis of molar equivalent amounts of potassium, we find that KOH activation generally produces porous carbons with larger fractions of mesopores (≥2 nm), while K2C2O4·H2O activation produces porous carbons with greater fractions of micropores (≤2 nm). Additionally, we investigate mechanisms of heteroatom loss during activation and find that nitrogen is exclusively sequestered in solid inorganic phases. Notably, differences in the surface properties of the resulting carbons are subtle. While surface nitrogen species are similar between both activation treatments, KOH activation produces materials with both a greater abundance and different types of surface oxygen species when compared to K2C2O4·H2O activation. Finally, we determine that the degree of carbon dioxide (CO2) adsorbed in the activated carbons at pressures up to 1 bar is primarily determined by the volume of small micropores (≤1 nm). Overall, this study seeks to provide a roadmap to tailor the surface and textural properties of heteroatom-doped porous carbons for gas storage, separations, and energy storage applications.

Because water is an integral part of day-to-day life for humans, civilizations have generally flourished either in coastal areas or near river basins. Today, about 40% of the world's population lives near a coast and many of the biggest cities are located near the sea or along rivers. In Norway, a high percentage of people live in coastal areas. There are many waterways, such as canals and fjords, in these coastal areas. Constructing bridges over these water channels is expensive and may hinder marine traffic. Therefore, in the coastal cities, urban ferries are much more than tourist attractions. They are an integral part of the city's mullimodal transportation system and essential for easing road traffic and congestion.

Onboard hybrid power systems with low -emission energy carriers are a promising solution for green shipping replacing conventional diesel engine -based energy systems. However, there are several existing challenges related to these new low -emission energy solutions that need to be investigated. A full-scale infrastructure for testing and verification of such systems is one of the important stepping stones while developing a reliable system. In this article, hybrid power systems for ships and the related controllers were discussed with a focus on the HPS Laboratory at NTNU as an infrastructure for the testing and verification of shipboard dc power systems. A hierarchical control architecture for the power and energy management of the hybrid power system was also detailed. The experimental verification of the energy management system for both the zero -emission and hybrid propulsion mode along with voltage droop power -sharing using the real ship load profile was presented.

We report the case of a 9-year-old girl who presented with acute fevers, cough, and epistaxis with nasal swelling, and found to have a nasal mass. On 18F-FDG PET/CT, she was found to have marked nodal and pulmonary parenchymal disease with diffuse and symmetrical mural FDG uptake within the trachea and bronchial tree. The differential diagnosis was broad, and she was diagnosed with IgG4-RD (IgG4-related disease) and improved on appropriate treatment. To our knowledge, there are only 2 other pediatric cases of IgG4-related pulmonary disease in the literature, and our case serves as a unique constellation of intrapulmonary IgG4-RD imaging findings.