Concept Design Methodology to Enable Naval Smart Grid onboard Electric Ships

The design of naval electric ships is a complex task, requiring the combined effort of several experts to provide a feasible, efficient, and effective design. In this regard, modifying an existing \u201cparent\u201d design still seems to be the easiest way to achieve cost reduction, acquisition process anticipation, and reduced technical risks. In last decades, many methods have been proposed to approach new design concepts. In this paper the authors support the use of set-based design (SBD) paradigm, especially at concept design stage, with the aim of identifying the best possible design enabling naval smart grid onboard. A synthesis is made of the primary properties of a number of baseline ships, to ease the metamodeling of ships\u201d attributes. The latter are used to drive a random mathematical design model in a MADM framework. A large set of feasible designs is generated by an adaptive Monte Carlo sampling, followed by identification of the Pareto frontier and selection of the best designs through a rank ordering. In this paper it is shown how the best non-dominated designs can improve performance, while providing a significant advantage compared with the baseline ships in terms of lower onboard occupied volumes and weight. The latter can then be used for installing additional equipment onboard the vessel, like energy storage systems, in order to enable the integration of modern and future electric systems. A preliminary assessment of the achievable energy storage capacity enabled by the SBD approach is also given, to allow evaluating the order of magnitude of the advantages provided by the SBD approach

Naval Smart Grid Preliminary Integration onboard Electric Ships

Innovation in platform systems, as well as requirements on energy efficiency, are pushing towards the naval vessels' electrification. In fact, the power required by new platform systems, sensors, and new subsystems (for supporting the latter) is so big to make either full or hybrid electric-propelled ships the new target for all but the smallest vessels. This makes the power system a critical system, whose onboard integration requires a significant effort. Several different power system architectures (e.g., ac vs dc, or radial vs. zonal) can be used to power the loads, exploiting different pros and cons depending on their peculiarities. While most of the focus is usually on topics regarding electric and survivability performance, the integrability of such architectures in a ship is less addressed. In this paper, three power system configurations (ac radial, de radial, dc zonal) for a multirole frigate are designed. Their correct onboard integration is then assessed, by means of 3D parametric models, and comparisons in terms of volumes and weights of all the main electrical components are provided. Moreover, a discussion about the effect of the proposed configurations on the overall ship arrangement is given, pointing out some useful considerations about the opportunity of decoupling power system and hull's design processes, provided that some conditions are verified

The first SARS-CoV-2 wave among pregnant women in Italy: results from a prospective population-based study

Introduction. This study aimed to estimate the incidence of SARS-CoV-2 infection among pregnant women during the first pandemic wave in Italy, and to describe COVID-19 disease characteristics and maternal and perinatal outcomes. Materials and methods. National population-based prospective cohort study collecting information on women with SARS-CoV-2 diagnosis, confirmed within 7 days from hospital admission. Results. The national SARS-CoV-2 rate was 6.04 per 1,000 births (95% CI 5.62-6.49) among pregnant women and 7.54 (95% CI 7.47-7.61) among women in reproductive age. 72.1% of the cohort developed mild COVID-19 disease without pneumonia nor need for ventilatory support. Severe disease was significantly associated with women's previous comorbidities (OR 2.55; 95% CI 0.98-6.90), obesity (OR 4.76; 95% CI 1.79-12.66) and citizenship from High Migration Pressure Countries (OR 3.43; 95% CI 1.27-9.25). Conclusions. During the first pandemic wave in Italy, the SARS-CoV-2 rate among pregnant women was lower compared to that detected among women of reproductive age, and risks of severe COVID-19 disease and adverse maternal and perinatal outcomes were rare

Childbirth Care among SARS-CoV-2 Positive Women in Italy

The new coronavirus emergency spread to Italy when little was known about the infection's impact on mothers and newborns. This study aims to describe the extent to which clinical practice has protected childbirth physiology and preserved the mother-child bond during the first wave of the pandemic in Italy. A national population-based prospective cohort study was performed enrolling women with confirmed SARS-CoV-2 infection admitted for childbirth to any Italian hospital from 25 February to 31 July 2020. All cases were prospectively notified, and information on peripartum care (mother-newborn separation, skin-to-skin contact, breastfeeding, and rooming-in) and maternal and perinatal outcomes were collected in a structured form and entered in a web-based secure system. The paper describes a cohort of 525 SARS-CoV-2 positive women who gave birth. At hospital admission, 44.8% of the cohort was asymptomatic. At delivery, 51.9% of the mothers had a birth support person in the delivery room; the average caesarean section rate of 33.7% remained stable compared to the national figure. On average, 39.0% of mothers were separated from their newborns at birth, 26.6% practised skin-to-skin, 72.1% roomed in with their babies, and 79.6% of the infants received their mother's milk. The infants separated and not separated from their SARS-CoV-2 positive mothers both had good outcomes. At the beginning of the pandemic, childbirth raised awareness and concern due to limited available evidence and led to "better safe than sorry" care choices. An improvement of the peripartum care indicators was observed over time