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In this paper, the d-dimensional quantum harmonic oscillator with a pseudo-differential time quasi-periodic perturbation i ψ ̇ = (− Δ + V (x) + ϵ W (ω t , x , − i ∇)) ψ , x ∈ R d is considered, where ω ∈ (0,2π)n, V (x) ≔ ∑ j = 1 d v j 2 x j 2 , v j ≥ v 0 > 0 , and W(θ, x, ξ) is a real polynomial in (x, ξ) of degree at most two, with coefficients belonging to Cℓ in θ ∈ T n for the order ℓ satisfying ℓ ≥ 2n + β, 0 < β < 1. Using the techniques developed by Bambusi et al. [Anal. PDE 11(3), 775–799 (2018)] and Rüssmann ["On optimal estimates for the solutions of linear partial differential equations of first order with constant coefficients on the torus," in Dynamical Systems, Theory and Applications, Lecture Notes in Physics Vol. 38 (Rencontres, Battelle Research Institute, Seattle, WA, 1975), pp. 598–624], this paper shows that for any ϵ small enough, there is a set D ϵ ⊂ (0 , 2 π) n with a big Lebesgue measure such that for any ω ∈ D ϵ , the system is reducible. [ABSTRACT FROM AUTHOR]

Identifying the influential factors in incident duration is important for traffic management agency to mitigate the impact of traffic incidents on freeway operation. Previous studies have proposed a variety of approaches to determine the significant factors for traffic incident clearance time. These methods commonly select a single "true" model among a majority of alternative models based on some model selection criteria. However, the conventional methods generally neglect the uncertainty related to the choice of models. This paper proposes a Bayesian Model Averaging (BMA) model to account for model uncertainty by averaging all plausible models using posterior probability as the weight. The BMA model is used to analyze the 2,584 freeway incident records obtained from I-5 corridor in Seattle, WA, USA. The results show that the BMA approach has the capability of interpreting the causal relationship between explanatory variables and clearance time. In addition, the BMA approach can provide better prediction performance than the Cox proportional hazards model and the accelerated failure time models. Overall, the findings in this study can be useful for traffic emergency management agency to apply an alternative methodology for predicting traffic incident clearance time when model uncertainty is considered. [ABSTRACT FROM AUTHOR]

This paper presents the structural response of prescriptively designed buckling restrained braced frame buildings to four ground motion sets with different fault characteristics. The four ground motion sets are characteristic of far field, near field with pulse, near field with no pulse, and subduction zone long duration earthquakes. Two prototype buildings of different heights were used for the analysis and designed for a site in Seattle, WA. The analysis was conducted using three-dimensional numerical models of the prototype buildings developed in OpenSeesPy. The simulated buckling restrained brace response was validated with three experimental tests from the literature. The analysis results were used to investigate the effect of ground motion type on the structural response parameters of inter story drift, peak floor velocity, peak floor acceleration, residual inter story drift, and cumulative ductility demand. Results show that the near field motions increase the inter story drift demand compared to far field and long duration motions. All motion sets were likely to cause some level of structural and non-structural damage to drift, velocity, and acceleration sensitive components at the DE and MCE R hazard levels, but severe damage states may not be highly likely. The median residual inter story drift was less than 0.5% for all motion sets. The cumulative ductility demand of the subduction zone long duration motion set was 5 to 6 times greater than that of the far field or near field motion sets and exceeded the code-minimum cumulative ductility for prequalification for upwards of 60% of the analyses. • Study results confirm that near-field earthquakes result in large story drift than far-field earthquakes. • Code-designed BRBFs are likely to have low levels of nonstructural damage. • Code-designed BRBFs are unlikely to have severe levels of nonstructural damage. • Long-duration earthquakes result in 5–6 times more cumulative ductility demand than near-field or far-field earthquakes. • Long-duration earthquakes have cumulative ductility demand in excess of minimum code requirements for pre-qualified BRBs. [ABSTRACT FROM AUTHOR]

First Person is a series of interviews with the first authors of a selection of papers published in Journal of Cell Science, helping early-career researchers promote themselves alongside their papers. Westley Heydeck is first author on ‘Tetrahymena Poc5 is a transient basal body component that is important for basal body maturation’, published in JCS. Westley conducted the research described in this article while a PhD student and scientific consultant in Professor Mark Winey's lab at the University of Colorado, Boulder, CO. He is now a Technical Application scientist at NanoString Technologies, Seattle, WA, where he is studying complex diseases using animal models and new technologies. [ABSTRACT FROM AUTHOR]