The Thaw

David Thaw

Freeze-Thaw Bayesian Optimization

In machine learning, the term “training” is used to describe the procedure of fitting a model to data. In many popular models, this fitting procedure is framed as an optimization problem, in which a loss is minimized as a function of the parameters. In all but the simplest machine learning models, this minimization must be performed with an iterative algorithm such as stochastic gradient descen...

Is the January Thaw a Statistical Phantom?

JANUARY 2002 AMERICAN METEOROLOGICAL SOCIETY | M eteorological conditions that tend to occur on or near a specific calendar date more frequently than chance might suggest have been termed singularities (e.g., Huschke 1959) or calendaricities, a term introduced by Brier et al. (1963) to avoid confusion with the mathematical usage of “singularities.” These features are commonly identified as cons...

Phototrophs in subarctic thaw lakes

Introduction Conclusions References

Freeze-thaw-induced embolism in Pinus contorta: centrifuge experiments validate the 'thaw-expansion hypothesis' but conflict with ultrasonic emission data.

*The 'thaw-expansion hypothesis' postulates that xylem embolism is caused by the formation of gas bubbles on freezing and their expansion on thawing. We evaluated the hypothesis using centrifuge experiments and ultrasonic emission monitoring in Pinus contorta. *Stem samples were exposed to freeze-thaw cycles at varying xylem pressure (P) in a centrifuge before the percentage loss of hydraulic c...