A 80µW 30fps 104 × 104 all-nMOS pixels CMOS imager with 7-bit PWM ADC for robust detection of relative intensity change

Author(s):  
Michele Benetti ◽  
Massimo Gottardi ◽  
Zeev Smilansky
2014 ◽  
Vol 70 (3) ◽  
pp. 291-299 ◽  
Author(s):  
Bertrand Fournier ◽  
Philip Coppens

Data collected during dynamic structure pump–probe crystallography experiments require appropriate indicators of agreement and tools to visualize the electron-density distribution changes. Agreement factors based on the ratio of intensitiesRwith and without the external perturbation are shown to be analogous to the {\cal R}1andw{\cal R}2{\cal R} factors widely used in standard crystallographic refinements. The η-based {\cal R} factors, normalized by the average relative intensity change, are significantly larger thanR-based values. It is shown that the relative intensity change η-based {\cal R} factors are not suitable for comparing different data sets. Fourier photodifference maps allow the visualization of the externally induced structural changes in the crystal, but also can be used during refinement to observe residual peaks not yet accounted for by the model and thus monitor the progress of the refinement. The photodeformation maps are a complementary tool to confirm the validity of the final model. Photodeformation maps with equalized laser-on and laser-off thermal motion are used to highlight the structural changes.


Abstract In a recent study by Wang et al. (2021a) that introduced a dynamical efficiency to the intensification potential of a tropical cyclone (TC) system, a simplified energetically based dynamical system (EBDS) model was shown to be able to capture the intensity-dependence of TC potential intensification rate (PIR) in both idealized numerical simulations and observations. Although the EBDS model can capture the intensity-dependence of TC intensification as in observations, a detailed evaluation has not yet been done. This study provides an evaluation of the EBDS model in reproducing the intensity-dependent feature of the observed TC PIR based on the best-track data for TCs over the North Atlantic, central, eastern and western North Pacific during 1982–2019. Results show that the theoretical PIR estimated by the EBDS model can capture basic features of the observed PIR reasonably well. The TC PIR in the best-track data increases with increasing relative TC intensity (intensity normalized by its corresponding maximum potential intensity–MPI) and reaches a maximum at an intermediate relative intensity around 0.6, and then decreases with increasing relative intensity to zero as the TC approaches its MPI, as in idealized numerical simulations. Results also show that the PIR for a given relative intensity increases with the increasing MPI and thus increasing sea surface temperature, which is also consistent with the theoretical PIR implied by the EBDS model. In addition, future directions to include environmental effects and make the EBDS model applicable to predict intensity change of real TCs are also discussed.


2002 ◽  
Author(s):  
John G. Neuhoff ◽  
Kimberly Fukai ◽  
John Preston ◽  
Kate Willaman

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