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    The evaluation of cEEGrids for fatigue detection in aviation
    (Oxford Academic, 2024) Klaren, C. van ; Maij, A. ; Marsman, L.A. ; Drongelen, A. van
    Operator fatigue poses a major concern in safety-critical industries such as aviation, potentially increasing the chances of errors and accidents. To better understand this risk, there is a need for noninvasive objective measures of fatigue. This study aimed to evaluate the performance of cEEGrids, a type of ear-EEG, for fatigue detection by analyzing the alpha and theta power before and after sleep restriction in four sessions on two separate days, employing a within-participants design. Results were compared to traditional, highly validated methods: the Karolinska Sleepiness Scale (KSS) and Psychomotor Vigilance Task (PVT). After sleep restriction and an office workday, 12 participants showed increased alpha band power in multiple electrode channels, but no channels correlated with KSS scores and PVT response speed. These findings indicate that cEEGrids can detect differences in alpha power following mild sleep loss. However, it should be noted that this capability was limited to specific channels, and no difference in theta power was observed. The study shows the potential and limitations of ear-EEG for fatigue detection as a less invasive alternative to cap-EEG. Further design and electrode configuration adjustments are necessary before ear-EEG can be implemented for fatigue detection in the field.
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    Is Urban Air Mobility Environmentally Feasible? Defining the Guidelines for a Sustainable Implementation of its Ecosystem
    (Elsevier, 2023) Tojal, M. ; Paletti, L.
    Urban Air Mobility (UAM) is commonly branded as the upcoming sustainable form of air mobility. Within the aviation sector, the adjective “sustainable” is almost exclusively used in relation with new forms of propulsion, particularly to electric and/or hydrogen energy sources, and in relation to noise levels caused by aviation activities. The same seems to apply for UAM. Limiting a sustainability assessment to the level of emissions (of all types) or of noise is not enough to generate a sustainable mobility system. This paper reviews the state of the art in the field of UAM and wants to assess how much the full meaning of “sustainability” is used in relation to UAM. Moreover, the paper reviews and defines a set of indicators to measure the sustainability of UAM.
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    Unsteady flow behaviour of multi-rotors in ground proximity
    (Cambridge University Press, 2023) Dekker, H.N.J. ; Baars, W.J. ; Scarano, F. ; Tuinstra, M. ; Ragni, D.
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    Quantitative microbial risk assessment of contracting COVID-19 derived from measured and simulated aerosol particle transmission in aircraft cabins
    (National Institute of Environmental Health Sciences, 2023) Schijven, J.F. ; Veen, T.A. van ; Delmaar, C. ; Kos, J. ; Vermeulen, L. ; Roosien, R.J. ; Verhoeven, F. ; Schipper, M. ; Peerlings, B. ; Duizer, E. ; Derei, J. ; Lammen, W.F. ; Bartels, O.J. ; Ven, H. van der ; Maas, R.
    Background SARS-CoV-2 can be effectively transmitted between individuals located in close proximity to each other for extended durations. Aircraft provide such conditions. Although high attack rates during flights were reported, little was known about the risk levels of aerosol transmission of SARS-CoV-2 in aircraft cabins. Objectives The major objective was to assess the risk of contracting COVID-19 from exposure to SARS-CoV-2-containing aerosol particles in aircraft cabins. Methods In two single-aisle and one twin-aisle aircraft, dispersion of generated aerosol particles over a 7-row economy-class cabin section was measured under cruise and taxi conditions and simulated with a CFD model under cruise conditions. Using the aerosol particle dispersion data, a quantitative microbial risk assessment was conducted for scenarios with an infectious person expelling SARS-CoV-2 virions in aerosol particles by breathing and speaking. Effects of flight conditions were evaluated using Generalized Additive Mixed Models. Results On a typical flight with an average shedder, mean risk of contracting COVID-19 ranged from 1.3×10-3 to 9.0×10-2 . Risk increased to 7.7×10-2 with a super shedder (<3% of cases) on a long flight. Risks increased with increasing flight duration: 2 – 23 cruise flights of typical duration and 2 – 10 flights of longer duration resulted in at least 1 case of COVID-19 due to onboard aerosol transmission by one average shedder and in the case of one super shedder, at least 1 case in 1 – 3 flights of typical duration cruise and 1 flight of longer duration. Risk decreased with increasing distance from the infectious person and this decrease varied with direction. A face mask reduced emission of the larger aerosol particles and altered the direction of the aerosol particles. Discussion From this study it can be concluded that although ventilation strongly reduces the risk of contracting COVID-19 by aerosol transmission in an aircraft cabin, residual aerosol particles containing virus continue to pose a risk. Obviously, testing before boarding will help reduce the chance of a (super)shedder boarding an aircraft and mask use further reduces aerosol transmission in the aircraft cabin.