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Artificial intelligence (AI) has potential to streamline interpretation of pH-impedance studies. In this exploratory observational cohort study, we determined feasibility of automated AI extraction of baseline impedance (AIBI) and evaluated clinical value of novel AI metrics.pH-impedance data from a convenience sample of symptomatic patients studied off (n = 117, 53.1 ± 1.2 years, 66% F) and on (n = 93, 53.8 ± 1.3 years, 74% F) anti-secretory therapy and from asymptomatic volunteers (n = 115, 29.3 ± 0.8 years, 47% F) were uploaded into dedicated prototypical AI software designed to automatically extract AIBI. Acid exposure time (AET) and manually extracted mean nocturnal baseline impedance (MNBI) were compared to corresponding total, upright, and recumbent AIBI and upright:recumbent AIBI ratio. AI metrics were compared to AET and MNBI in predicting ≥ 50% symptom improvement in GERD patients.Recumbent, but not upright AIBI, correlated with MNBI. Upright:recumbent AIBI ratio was higher when AET 6% (median 1.18, IQR 1.0-1.5), compared to 4% (0.95, IQR 0.84-1.1), 4-6% (0.89, IQR 0.72-0.98), and controls (0.93, IQR 0.80-1.09, p ≤ 0.04). While MNBI, total AIBI, and the AIBI ratio off PPI were significantly different between those with and without symptom improvement (p 0.05 for each comparison), only AIBI ratio segregated management responders from other cohorts. On ROC analysis, off therapy AIBI ratio outperformed AET in predicting GERD symptom improvement when AET was 6% (AUC 0.766 vs. 0.606) and 4-6% (AUC 0.563 vs. 0.516) and outperformed MNBI overall (AUC 0.661 vs. 0.313).BI calculation can be automated using AI. Novel AI metrics show potential in predicting GERD treatment outcome.

Inflatable wings provide a compact alternative for aircraft that need to fit into small volumes before deployment, such as backpack unmanned aircraft or rocket-delivered air vehicles. Common inflatable designs use inflation chambers separated by spanwise baffles, generating a naturally undulating airfoil surface. Early wind tunnel tests of these designs showed evidence that separation over these airfoils was reduced compared to their smooth counterparts. Subsequent efforts to replicate these advantages computationally have proven ambiguous—while under certain conditions the inflatable airfoil may improve the lift-todrag characteristics of the wing, in other conditions the inflatable profile appears detrimental. Currently, these wings are being investigated through a combination of twodimensional and three-dimensional simulations and physical experiments. The initial targets of these comparisons are moderate Reynolds number (~10 5 ) flows, comparable to known flight conditions of inflatable wing UAVs. This places the flows in a naturally transitional regime, presenting additional complications in attempting to reconcile the results for these different investigative techniques.

Inflatable wings provide a compact alternative for aircraft that need to fit into small volumes before deployment, such as backpack unmanned aircraft or rocket-delivered air vehicles. The naturally undulating airfoil surface created by the inflation chambers may also provide an opportunity for flow control, as early wind tunnel tests indicated that separation over these airfoils was reduced compared to their smooth counterparts. Subsequent efforts to replicate these advantages computationally have proven ambiguous— while under certain conditions the inflatable airfoil may improve the lift-to-drag characteristics of the wing, in other conditions the inflatable profile appears detrimental. Further, these results have not been satisfactorily compared to experiments to confirm their validity. To attempt to address this, a series of PIV measurements has been taken for both a bumpy and smooth NACA 4318 airfoil at varying Reynolds number and angle of attack. This data is compared to CFD simulations in order to validate the models and gain further insight in to the flow physics. The combined computational/experimental analysis will allow for a better determination of the performance penalty or benefit that occurs due to the bumpy surface. Select three-dimensional simulations will also be used to further illuminate the effects of the bumpy surface on the aerodynamics.