Urban Air Mobility (UAM) has the ability to reduce ground traffic congestion by enabling rapid on-demand flight through three-dimensional airspace with zero operational emissions by using electric Vertical TakeOff and Landing (eVTOL) vehicles. In the long term with more UAM flights, air traffic control is expected to limit further growth of such operations. Therefore, a first research has been performed on energy-efficient trajectory optimisation for a given required time of arrival, as the arrival phase is the most safety-critical flight phase with much higher air traffic density and limited battery energy. However, research on the computation of the optimal required time of arrival (RTA) for eVTOL aircraft has not yet been performed. Unlike fixed-wing aircraft or helicopters in commercial aviation, eVTOL aircraft have different flight dynamics, limited battery energy supply and a limited number of landing spots at a vertiport such as the top of high-rise buildings. This work is the first to utilise a mixed-integer linear program that computes the optimal RTAs for eVTOLs to safely separate them for minimum delay based on remaining battery state of charge and vertiport capacity. A concept of operations for vertiport terminal area airspace design is also proposed while making use of the existing energy-efficient trajectory optimisation tool. The research serves as a basis for further development of safe and efficient UAM operations. The mathematical model can also be applied to Unmanned Aircraft System Traffic Management (UTM) by inserting new separation requirements and flight dynamics for smaller drones when optimising a high density arrival terminal airspace.
A fluorescent probe for Cu(II) ion is presented. It is based on the rhodamine fluorophore and exhibits high selectivity and sensitivity for Cu(II) ion in aqueous methanol (2:8, v/v) at pH 7.0. The response is based on a ring opening reaction and formation of a strongly fluorescent 1:1 complex. The response is reversible and linear in the range between 50 nM and 900 nM, with a detection limit of 7.0 nM. The probe was successfully applied to fluorescent imaging of Cu(II) ions in HeLa cells.
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