47 research outputs found

    Oceanic Challenges to Technological Solutions : A Review of Autonomous Underwater Vehicle Path Technologies in Biomimicry, Control, Navigation, and Sensing

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    Autonomous Underwater Vehicles (AUVs) epitomize a revolutionary stride in underwater exploration, seamlessly assuming tasks once exclusive to manned vehicles. Their collaborative prowess within joint missions has inaugurated a new epoch of intricate applications in underwater domains. This study’s primary aim is to scrutinize recent technological advancements in AUVs and their role in navigating the complexities of underwater environments. Through a meticulous review of literature and empirical studies, this review synthesizes recent technological strides, spotlighting developments in biomimicry models, cutting-edge control systems, adaptive navigation algorithms, and pivotal sensor arrays crucial for exploring and mapping the ocean floor. The article meticulously delineates the profound impact of AUVs on underwater robotics, offering a comprehensive panorama of advancements and illustrating their far-reaching implications for underwater exploration and mapping. This review furnishes a holistic comprehension of the current landscape of AUV technology. This condensed overview furnishes a swift comparative analysis, aiding in discerning the focal points of each study while spotlighting gaps and intersections within the existing body of knowledge. It efficiently steers researchers toward complementary sources, enabling a focused examination and judicious allocation of time to the most pertinent studies. Furthermore, it functions as a blueprint for comprehensive studies within the AUV domain, pinpointing areas where amalgamating multiple sources would yield a more comprehensive understanding. By elucidating the purpose, employing a robust methodology, and anticipating comprehensive results, this study endeavors to serve as a cornerstone resource that not only encapsulates recent technological strides but also provides actionable insights and directions for advancing the field of underwater robotics.© 2024 The Authors. This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License. For more information, see https://creativecommons.org/licenses/by-nc-nd/4.0/fi=vertaisarvioitu|en=peerReviewed

    KNH2 - KH: a metal amide - hydride solid solution

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    We report for the first time the formation of a metal amide-hydride solid solution. The dissolution of KH into KNH2 leads to an anionic substitution, which decreases the interaction among NH2 - ions. The rotational properties of the high temperature polymorphs of KNH2 are thereby retained down to room temperature.Fil: Santoru, Antonio. Helmholtz-zentrum Geesthacht; Alemania. Università di Torino; ItaliaFil: Pistidda, Claudio. Helmholtz-zentrum Geesthacht; AlemaniaFil: Sørby, Magnus H.. Institute for Energy Technology. Physics Department; NoruegaFil: Chierotti, Michele R.. Università di Torino; ItaliaFil: Garroni, Sebastian. University of Sassari; ItaliaFil: Pinatel, Eugenio. Università di Torino; ItaliaFil: Karimi, Fahim. Helmholtz-zentrum Geesthacht; AlemaniaFil: Cao, Hujun. Helmholtz-zentrum Geesthacht; AlemaniaFil: Bergemann, Nils. Helmholtz-zentrum Geesthacht; AlemaniaFil: Le, Thi T.. Helmholtz-zentrum Geesthacht; AlemaniaFil: Puszkiel, Julián Atilio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; ArgentinaFil: Gobetto, Roberto. Università di Torino; ItaliaFil: Baricco, Marcello. Università di Torino; ItaliaFil: Hauback, Bjorn C.. Institute for Energy Technology. Physics Department; NoruegaFil: Klassen, Thomas. Helmholtz-zentrum Geesthacht; AlemaniaFil: Dornheim, Martín. Helmholtz-zentrum Geesthacht; Alemani

    Influence of milling parameters on the sorption properties of the LiH-MgB2 system doped with TiCl3

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    Abstract Hydrogen sorption properties of the LiH-MgB2 system doped with TiCl3 were investigated with respect to milling conditions (milling times, ball to powder (BTP) ratios, rotation velocities and degrees of filling) to form the reactive hydride composite (RHC) LiBH4-MgH2. A heuristic model was applied to approximate the energy transfer from the mill to the powders. These results were linked to experimentally obtained quantities such as crystallite size, specific surface area (SSA) and homogeneity of the samples, using X-ray diffraction (XRD), the Brunauer-Emmett-Teller (BET) method and scanning electron microscopy (SEM), respectively. The results show that at approximately 20 kJ g-1 there are no further benefits to the system with an increase in energy transfer. This optimum energy transfer value indicates that a plateau was reached for MgB2 crystallite size therefore the there was also no improvement of reaction kinetics due to no change in crystallite size. Therefore, this study shows that an optimum energy transfer value was reached for the LiH-MgB2 system doped with TiCl3.Fil: Busch, Nina. Helmholtz-zentrum Geesthacht; AlemaniaFil: Jepsen, Julian. Helmholtz-zentrum Geesthacht; AlemaniaFil: Pistidda, Claudio. Helmholtz-zentrum Geesthacht; AlemaniaFil: Puszkiel, Julián Atilio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; ArgentinaFil: Karimi, Fahim. Helmholtz-zentrum Geesthacht; AlemaniaFil: Milanese, Chiara. Universita degli Studi di Pavia; ItaliaFil: Tolkiehn, Martin. Helmholtz-zentrum Geesthacht; AlemaniaFil: Chaudhary, Anna Lisa. Helmholtz-zentrum Geesthacht; AlemaniaFil: Klassen, Thomas. Helmholtz-zentrum Geesthacht; AlemaniaFil: Dornheim, Martin. Helmholtz-zentrum Geesthacht; Alemani

    Design of a Nanometric AlTi Additive for MgB2-Based Reactive Hydride Composites with Superior Kinetic Properties

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    Solid-state hydride compounds are a promising option for efficient and safe hydrogen-storage systems. Lithium reactive hydride composite system 2LiBH4 + MgH2/2LiH + MgB2 (Li-RHC) has been widely investigated owing to its high theoretical hydrogen-storage capacity and low calculated reaction enthalpy (11.5 wt % H2 and 45.9 kJ/mol H2). In this paper, a thorough investigation into the effect of the formation of nano-TiAl alloys on the hydrogen-storage properties of Li-RHC is presented. The additive 3TiCl3·AlCl3 is used as the nanoparticle precursor. For the investigated temperatures and hydrogen pressures, the addition of ∼5 wt % 3TiCl3·AlCl3 leads to hydrogenation/dehydrogenation times of only 30 min and a reversible hydrogen-storage capacity of 9.5 wt %. The material containing 3TiCl3·AlCl3 possesses superior hydrogen-storage properties in terms of rates and a stable hydrogen capacity during several hydrogenation/dehydrogenation cycles. These enhancements are attributed to an in situ nanostructure and a hexagonal AlTi3 phase observed by high-resolution transmission electron microscopy. This phase acts in a 2-fold manner, first promoting the nucleation of MgB2 upon dehydrogenation and second suppressing the formation of Li2B12H12 upon hydrogenation/dehydrogenation cycling.Fil: Le, Thi-Thu. Helmholtz Zentrum Geesthacht; AlemaniaFil: Pistidda, Claudio. Helmholtz Zentrum Geesthacht; AlemaniaFil: Puszkiel, Julián Atilio. Helmholtz Zentrum Geesthacht; Alemania. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; ArgentinaFil: Castro Riglos, Maria Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Helmholtz Zentrum Geesthacht; Alemania. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; ArgentinaFil: Karimi, Fahim. Helmholtz Zentrum Geesthacht; AlemaniaFil: Skibsted, Jørgen. University Aarhus; DinamarcaFil: Gharibdoust, Seyedhosein Payandeh. University Aarhus; DinamarcaFil: Richter, Bo. University Aarhus; DinamarcaFil: Emmler, Thomas. Helmholtz Zentrum Geesthacht; AlemaniaFil: Milanese, Chiara. Università di Pavia; ItaliaFil: Santoru, Antonio. Helmholtz Zentrum Geesthacht; AlemaniaFil: Hoell, Armin. Helmholtz Zentrum Berlin für Materialien und Energie; AlemaniaFil: Krumrey, Michael. Physikalisch Technische Bundesanstalt; AlemaniaFil: Gericke, Eike. Universität zu Berlin; AlemaniaFil: Akiba, Etsuo. Kyushu University; JapónFil: Jensen, Torben R.. University Aarhus; DinamarcaFil: Klassen, Thomas. Helmholtz Zentrum Geesthacht; Alemania. Helmut Schmidt University; AlemaniaFil: Dornheim, Martin. Helmholtz Zentrum Geesthacht; Alemani

    Towards machine vision for insect welfare monitoring and behavioural insights

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    Machine vision has demonstrated its usefulness in the livestock industry in terms of improving welfare in such areas as lameness detection and body condition scoring in dairy cattle. In this article, we present some promising results of applying state of the art object detection and classification techniques to insects, specifically Black Soldier Fly (BSF) and the domestic cricket, with the view of enabling automated processing for insect farming. We also present the low-cost “Insecto” Internet of Things (IoT) device, which provides environmental condition monitoring for temperature, humidity, CO2, air pressure, and volatile organic compound levels together with high resolution image capture. We show that we are able to accurately count and measure size of BSF larvae and also classify the sex of domestic crickets by detecting the presence of the ovipositor. These early results point to future work for enabling automation in the selection of desirable phenotypes for subsequent generations and for providing early alerts should environmental conditions deviate from desired values

    Sorption behavior of the MgH2-Mg2FeH6 hydride storage system synthesized by mechanical milling followed by sintering

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    The hydrogen sorption behavior of the Mg2FeH6eMgH2hydride system is investigated via in-situ synchrotron and laboratory powder X-ray diffraction (SR-PXD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), particle size distribution (PSD) and volumetric techniques. The Mg2FeH6eMgH2 hydride system is obtained by mechanical milling in argon atmosphere followed by sintering at high temperature and hydrogen pressure. In-situ SR-PXD results show that upon hydriding MgH2 is a precursor for Mg2FeH6 formation and remained as hydrided phase in the obtained material. Diffusion constraints preclude the further formation of Mg2FeH6. Upon dehydriding, our results suggest that MgH2 and Mg2FeH6 decompose independently in a narrow temperature range between 275 and 300 C. Moreover, the decomposition behavior of both hydrides in the Mg2FeH6eMgH2 hydride mixture is influenced by each other via dual synergetic-destabilizing effects. The final hydriding/dehydriding products and therefore the kinetic behavior of the Mg2FeH6eMgH2 hydride system exhibits a strong dependence on the temperature and pressure conditions.Fil: Puszkiel, Julián Atilio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica; ArgentinaFil: Gennari, Fabiana Cristina. Comision Nacional de Energia Atomica. Gerencia de Area de Aplicaciones de la Tecnologia Nuclear. Gerencia de Investigacion Aplicada; . Universidad Nacional de Cuyo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Arneodo Larochette, Pierre Paul. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comision Nacional de Energia Atomica. Gerencia de Area de Aplicaciones de la Tecnologia Nuclear. Gerencia de Investigacion Aplicada; . Universidad Nacional de Cuyo; ArgentinaFil: Karimi, Fahim. Materials Technology. Institute of Materials Research; AlemaniaFil: Pistidda, Claudio. Materials Technology. Institute of Materials Research; AlemaniaFil: Gosalawit Utke, Rapee. Materials Technology. Institute of Materials Research; Alemania. Suranaree University of Technology. Institute of Science, School of Chemistry; TailandiaFil: Jepsen, Julian. Materials Technology. Institute of Materials Research; AlemaniaFil: Jensen, Torben R.. University of Aarhu. Center for Energy Materials, iNANO and Department of Chemistry; DinamarcaFil: Gundlach, Carsten. Lund University. MAX-lab; SuizaFil: Bellosta von Colbe, José. Materials Technology. Institute of Materials Research; AlemaniaFil: Klassen, Thomas. Materials Technology. Institute of Materials Research; AlemaniaFil: Dornheim, Martin. Materials Technology. Institute of Materials Research; Alemani

    Medeuro : the longing for identity and community among Maltese migrant settlers in North Africa

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    Based largely on materials held in the Service des Periodiques at the Bibliotheque Nationale de Tunisie in Tunis, and especially on content anaylsis of a 1930s newspaper Melita published in Sousse. this study explores the yearning for and the anguish of a cultural survivance among Maltese migrant settlers in North Africa, above all the retention of Maltese as a language of expression, affinity and identification, at a time when Maltese itself was experiencing a literary rebirth. However, such a campaign is undertaken in a 'non-Maltese' context, where moreover, in addition to separation and distance, the influence of European empires-the French, the British and the Italian-is pronounced, if not dominant, thus interfering with any continued loyalty to one mother tongue or mother country. Masterminding the intellectual push for a collective self-identity anchored in language, literature, history and religion, is a leading francophone litterateur whose family had settled in Algeria from the island of Gozo. What is also offered here, in the annotations, is a fairly comprehensive bibliography of Maltese migrant settlement in northern Africa with special reference to lesser known articles and other publications not available in English.peer-reviewe

    Global, regional, and national burden of disorders affecting the nervous system, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021

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    BackgroundDisorders affecting the nervous system are diverse and include neurodevelopmental disorders, late-life neurodegeneration, and newly emergent conditions, such as cognitive impairment following COVID-19. Previous publications from the Global Burden of Disease, Injuries, and Risk Factor Study estimated the burden of 15 neurological conditions in 2015 and 2016, but these analyses did not include neurodevelopmental disorders, as defined by the International Classification of Diseases (ICD)-11, or a subset of cases of congenital, neonatal, and infectious conditions that cause neurological damage. Here, we estimate nervous system health loss caused by 37 unique conditions and their associated risk factors globally, regionally, and nationally from 1990 to 2021.MethodsWe estimated mortality, prevalence, years lived with disability (YLDs), years of life lost (YLLs), and disability-adjusted life-years (DALYs), with corresponding 95% uncertainty intervals (UIs), by age and sex in 204 countries and territories, from 1990 to 2021. We included morbidity and deaths due to neurological conditions, for which health loss is directly due to damage to the CNS or peripheral nervous system. We also isolated neurological health loss from conditions for which nervous system morbidity is a consequence, but not the primary feature, including a subset of congenital conditions (ie, chromosomal anomalies and congenital birth defects), neonatal conditions (ie, jaundice, preterm birth, and sepsis), infectious diseases (ie, COVID-19, cystic echinococcosis, malaria, syphilis, and Zika virus disease), and diabetic neuropathy. By conducting a sequela-level analysis of the health outcomes for these conditions, only cases where nervous system damage occurred were included, and YLDs were recalculated to isolate the non-fatal burden directly attributable to nervous system health loss. A comorbidity correction was used to calculate total prevalence of all conditions that affect the nervous system combined.FindingsGlobally, the 37 conditions affecting the nervous system were collectively ranked as the leading group cause of DALYs in 2021 (443 million, 95% UI 378–521), affecting 3·40 billion (3·20–3·62) individuals (43·1%, 40·5–45·9 of the global population); global DALY counts attributed to these conditions increased by 18·2% (8·7–26·7) between 1990 and 2021. Age-standardised rates of deaths per 100 000 people attributed to these conditions decreased from 1990 to 2021 by 33·6% (27·6–38·8), and age-standardised rates of DALYs attributed to these conditions decreased by 27·0% (21·5–32·4). Age-standardised prevalence was almost stable, with a change of 1·5% (0·7–2·4). The ten conditions with the highest age-standardised DALYs in 2021 were stroke, neonatal encephalopathy, migraine, Alzheimer's disease and other dementias, diabetic neuropathy, meningitis, epilepsy, neurological complications due to preterm birth, autism spectrum disorder, and nervous system cancer.InterpretationAs the leading cause of overall disease burden in the world, with increasing global DALY counts, effective prevention, treatment, and rehabilitation strategies for disorders affecting the nervous system are needed
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