In this work, over a thousand maritime casualty reports were reviewed in order to fully investigate and assess selected 213 marine accidents concerning the collision, grounding, and hull failure of ships, which occurred during the time period of 1990–2020, worldwide. Ship type and vessels’ main characteristics, as well as the cause of accidents, were categorized and analyzed statistically. The statistical software IBM SPSS© Statistics v.29 was employed for the investigation of a possible association between the above set criteria. Furthermore, the location and the extent of hull damage was extracted for all incidents, providing valuable insights into the resulting consequences for vessel integrity. These data are essential for estimating the accident’s impact on the viability of the ship, crew, and cargo. According to the main results obtained, significant correlations are deduced regarding the analyzed parameters. In collision accidents, these include the ship type, the location of the damage, visibility and age of the ship, the impact of the accident, and the type of casualty. In the case of grounding incidents, correlations emerge involving the type of ships, day/night period, the width of the resulting damage, the type of casualty, and the cause of accidents.

This work concerns the design, fabrication, and testing of a novel air-flow sensor employing exclusively additive manufacturing that can be fabricated on-site, aboard a ship, or in a similarly remote area, without relying on external manufacturing facilities. The developed device’s principle of operation is based on vortex shedding; its novelty focuses on employing solely additive manufacturing technology, for the manufacturing—in a single process step—of all the sensor’s main elements. In more detail, the required flow-shaping housing, the appropriate piezoresistive sensing element, and the electrical interconnection pads are all constructed in a single process step, through standard Fused Deposition Modeling (FDM) 3D technology. Direct communication to the necessary readout circuitry can be easily achieved through standard soldering utilizing the integrated contact pads of the sensor. The prototype was preliminary characterized, validating its proper functionality. Key features of the proposed device are low cost, fast on-site manufacturing of the entire measuring device, robustness, and simplicity, suggesting numerous potential applications in the shipbuilding industry and other industrial sectors.

Reduced graphene oxide (rGO) is a derivative of graphene, which has been widely used as the conductive pigment of many water-based inks and is recognized as one of the most promising graphene-based materials for large-scale and low-cost production processes. In this work, we evaluate a custom functionalised reduced graphene oxide ink (f–rGO) via inkjet-printing technology. Test line structures were designed and fabricated by the inkjet printing process using the f–rGO ink on a pretreated polyimide substrate. For the electrical characterisation of these devices, two-point (2P) and four-point (4P) probe measurements were implemented. The results showed a major effect of the number of printed passes on the resulting resistance for all ink concentrations in both 2P and 4P cases. Interesting results can be extracted by comparing the obtained multipass resistance values that results to similar effective concentration with less passes. These measurements can provide the ground to grasp the variation in resistance values due to the different ink concentrations, and printing passes and can provide a useful guide in achieving specific resistance values with adequate precision. Accompanying topography measurements have been conducted with white-light interferometry. Furthermore, thermal characterisation was carried out to evaluate the operation of the devices as temperature sensors and heaters. It has been found that ink concentration and printing passes directly influence the performance of both the temperature sensors and heaters.