In an emerging trajectory-based operation (TBO) environment within the advanced autonomous airspace, traffic operation along reference trajectories can function as trajectory-following mechanisms. However, 5G-based following dynamics still remain underexplored, limiting further utilization of lower-latency 5G technology other than data links. This limitation affects air traffic stability when encountering disturbance, preventing autonomous airspeed adjustment, and safe separation without air traffic controller interventions.
View Article and Find Full Text PDFSolar-driven interfacial evaporation presents significant potential for seawater desalination and wastewater purification. However, prolonged operation in marine environments often results in salt accumulation, which adversely impacts the performance and lifetime of system. Despite the progress in material design, achieving efficient evaporation while mitigating salt crystallization remains challenging in high-salinity water.
View Article and Find Full Text PDFCarbon capture and storage (CCS) of CO is a key technology for substantially mitigating global greenhouse gas emissions. Determining the biogeochemical processes in host rocks after CO injection informs the viability of carbon storage as a long-term sink for CO, the complexity of reservoir CH cycling, as well as the direct and indirect environmental impacts of this strategy. The doubly substituted ('clumped') isotopologues of methane (CHD and CHD) provide novel insights into methane origins and post-generation processing.
View Article and Find Full Text PDFSensors (Basel)
February 2024
Digital modelling stands as a pivotal step in the realm of Digital Twinning. The future trend of Digital Twinning involves automated exploration and environmental modelling in complex scenes. In our study, we propose an innovative solution for robot odometry, path planning, and exploration in unknown outdoor environments, with a focus on Digital modelling.
View Article and Find Full Text PDFAmino acids in carbonaceous chondrites may have seeded the origin of life on Earth and possibly elsewhere. Recently, the return samples from a C-type asteroid Ryugu were found to contain amino acids with a similar distribution to Ivuna-type CI chondrites, suggesting the potential of amino acid abundances as molecular descriptors of parent body geochemistry. However, the chemical mechanisms responsible for the amino acid distributions remain to be elucidated particularly at low temperatures (<50°C).
View Article and Find Full Text PDFStrain sensing technology using fibre Bragg grating (FBG) sensors is an attractive capability for aerospace structural health monitoring (SHM) and assessment because they offer resistance to harsh environments, low maintenance, and potential for high density and high strain sensing. The development of FBG inscription techniques through the fibre polymer coating using infrared (IR) lasers has overcome the mechanical weaknesses introduced by removal of the fibre coating, which is typically required for conventional UV laser inscription of FBGs. Type I and Type II femtosecond gratings are fabricated using through-coating inscription techniques, but the higher laser energy used for Type II gratings damages the glass fibre core, impacting mechanical performance.
View Article and Find Full Text PDFUnderstanding hydrocarbon cycling in the subsurface is important in various disciplines including climate science, energy resources and astrobiology. Mud volcanoes provide insights into biogeochemical processes occurring in the subsurface. They are usually associated with natural gas reservoirs consisting mainly of methane and other hydrocarbons as well as CO.
View Article and Find Full Text PDFOver the past 15 years, massive gas hydrate deposits have been studied extensively in Joetsu Basin, Japan Sea, where they are associated primarily with active gas chimney structures. Our research documents the discovery of spheroidal microdolomite aggregates found in association with other impurities inside of these massive gas hydrates. The microdolomites are often conjoined and show dark internal cores occasionally hosting saline fluid inclusions.
View Article and Find Full Text PDFAlthough fibre Bragg gratings (FBGs) offer obvious potential for use in high-density, high-strain sensing applications, the adoption of this technology in the historically conservative aerospace industry has been slow. There are several contributing factors, one of which is variability in the reported performance of these sensors in harsh and fatigue prone environments. This paper reports on a comparative evaluation of the fatigue performance of FBG sensors written according to the same specifications using three different grating manufacturing processes: sensors written in stripped and re-coated fibres, sensors written during the fibre draw process and sensors written through fibre coating.
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