Supernovae, an accelerating universe and the cosmological constant

Observations of supernova explosions halfway back to the Big Bang give plausible evidence that the expansion of the universe has been accelerating since that epoch, approximately 8 billion years ago and suggest that energy associated with the vacuum itself may be responsible for the acceleration.

A fast marching level set method for monotonically advancing fronts.

A fast marching level set method is presented for monotonically advancing fronts, which leads to an extremely fast scheme for solving the Eikonal equation. Level set methods are numerical techniques for computing the position of propagating fronts. They rely on an initial value partial differential equation for a propagating level set function and use techniques borrowed from hyperbolic conservation laws. Topological changes, corner and cusp development, and accurate determination of geometric properties such as curvature and normal direction are naturally obtained in this setting. This paper describes a particular case of such methods for interfaces whose speed depends only on local position. The technique works by coupling work on entropy conditions for interface motion, the theory of viscosity solutions for Hamilton-Jacobi equations, and fast adaptive narrow band level set methods. The technique is applicable to a variety of problems, including shape-from-shading problems, lithographic development calculations in microchip manufacturing, and arrival time problems in control theory.

Alternative-fueled vehicles: progress made in accelerating federal purchases, but benefits and costs remain uncertain.

Mode of access: Internet.

Patent artificial slate manufactory, Woodford Bridge, Essex : for covering roofs, fronts of houses, and bricks : also water pipes and gutters.

Amendment leaf between p. 16-17.

Full road closure for work zone operations : a case study : accelerating construction and reducing crashes during the rehabilitation of a major downtown route : M-10 Lodge Freeway in Detroit, Michigan.

"FHWA-HOP-05-013"--P. [4] of cover.

From mud to mufti with old Bill on all fronts,

Mode of access: Internet.

Carpentry : being a comprehensive guide book for carpentry and joinery : with elementary rules for the drawing of architecture in perspective and by geometrical rule : also, treating of roofs, trussed girders, floors, domes, stair-cases and hand-rails, shop fronts, verandahs, window-frames,shutters, &c. &c., and public and domestic buildings, with plans, elevations, sections, &c. &c./

Mode of access: Internet.