Quantum thermodynamics: Thermodynamics at the nanoscale

Abstract

A short introduction on quantum thermodynamics is given and three new topics are discussed. (1) Maximal work extraction from a finite quantum system. The thermodynamic prediction fails and a new, general result is derived, the ‘ergotropy’. (2) In work extraction from two-temperature set-ups, the presence of correlations can push the effective efficiency beyond the Carnot bound. (3) In the presence of level crossing, non-slow changes may be more optimal than slow ones.     

Display of profiled sweep objects

A class of free-form solids called profiled sweep objects is defined by four parametric curves: a 2D contour (cross-section), a 3D trajectory (spine), and two profile curves, which control the scaling of the contour as it moves along the trajectory. Subclasses of this are profiled prisms, which have a linear trajectory, and profiled generalized cylinders, which have an arbitrary 3D trajectory. First an exact definition of profiled sweep object, is presented and their relation with common sweep objects is described. Then a method is given for the construction of planar approximations of these objects that can be used for fast display generation. Finally, ray-tracing algorithms are given that directly use the exact definition for high-quality display.     

Visual, cognitive, and neurodevelopmental outcome at 51/2 years in children with perinatal haemorrhagic-ischaemic brain lesions

To determine predictive values of early visual and neurocognitive assessment in children with perinatally acquired haemorrhagic or ischaemic brain lesions selected on the basis of ultrasound, 63 children (37 boys, 26 girls), who had been followed and examined until the age of 18 months, were reexamined at 5 1/2 years. Good correlations between visual and neurodevelopmental assessments at 18 months and at 5 1/2 years were found. When ultrasound abnormalities were combined with early visual and neurocognitive assessment data, good predictive values, especially for the group of children who had grade 2 to 4 leukomalacia, were found for visual acuity and neurodevelopment.