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Let G$G$ be a semiabelian variety defined over an algebraically closed field K$K$, endowed with a rational self‐map Φ$\Phi$. Let α∈G(K)$\alpha \in G(K)$ and let Γ⊆G(K)$\Gamma \subseteq G(K)$ be a finitely generated subgroup. We show that the set {n∈N:Φn(α)∈Γ}$\lbrace n\in \mathbb {N} \colon \Phi ^n(\alpha)\in \Gamma \rbrace$ is a union of finitely many arithmetic progressions along with a set S$S$ of Banach density equal to 0$\hskip.001pt 0$. In addition, assuming that Φ$\Phi$ is regular, we prove that the set S$S$ must be finite. [ABSTRACT FROM AUTHOR]

We give examples of birational selfmaps of Pd,d⩾3$\mathbb {P}^d, d \geqslant 3$, whose dynamical degree is a transcendental number. This contradicts a conjecture by Bellon and Viallet. The proof uses a combination of techniques from algebraic dynamics and diophantine approximation. [ABSTRACT FROM AUTHOR]

We examined the impact of sharing periscope imagery and analysis tools in eighteen five-member teams (Sonar, Periscope, 2xTrack Motion Analysts, Track Manager) who undertook simulated submarine patrol tasks. Compared to a baseline condition, sharing imagery to team members increased perceived individual workload, with no improvement to team performance (tactical picture accuracy). When both imagery and analysis tools were shared, perceived workload increased and tactical picture compilation was more accurate. Despite this improved tactical picture for the imagery and analysis tools condition, there was no advantage to mission completion (rendezvous/close contact detection) or situation awareness. In contrast to the increased subjective workload, individuals in teams provided with shared imagery (with or without tools) had a lower physiological response (heart rate, electrodermal) to task demands compared to the baseline condition. Sharing imagery and analysis tools likely benefited tactical picture compilation by enabling dynamic task redistribution and multiple streams of concurrent data analysis. • Sharing periscope imagery increased perceived workload. • Sharing imagery did not improve team performance. • Sharing imagery and analysis tools improved team performance. • No impact on situation awareness or submarine mission completion. • Lower physiological response to task demands when imagery shared. [ABSTRACT FROM AUTHOR]