Ice streams are fast flowing bands of ice separated from stagnant ridges by shear margins. The mechanisms controlling the location of the margins remain unclear. We use published ice deformation data and a simple one-dimensional thermal model to show that West Antarctic ice stream margins have temperate ice over a substantial fraction of their thickness, a condition that may control their width...

We present a new method for first person sketch-based editing of terrain models. As in usual artistic pictures, the input sketch depicts complex silhouettes with cusps and T-junctions, which typically correspond to non-planar curves in 3D. After analysing depth constraints in the sketch based on perceptual cues, our method best matches the sketched silhouettes with silhouettes or ridges of the ...

The novelty of this study is presentation of an exact solution for prediction of postbuckling behavior of shear deformable micro- and nano-scale beams based on modified couple stress theory and using principle of minimum potential energy. Timoshenko and Reddy-Levinson beam theories are applied to consider the shear deformation effect and Von Karman nonlinear kinematics is used to describe the n...

Vulval cones of four closely related Heterodera species - H. glycines (races 1-5), H. lespedezae, H. schachtii, and H. trifolii - were examined using scanning electron microscopy. Numbers of dorsal and ventral radial ridges, total radial ridges, perineal ridges, and preanal ridges were useful in differentiating the five races of H. glycines and the other three species. Most of the populations d...

Galileo stereo images covering about 1500 km 2 of Uruk Sulcus on Ganymede have revealed two scales of ridges; (1) large-scale ridges and troughs spaced -6 km apart, corresponding to the "grooves" seen in Voyager images, and (2) small-scale ridges spaced hundreds of meters apart superimposed on the large-scale ridges. We interpret the small-scale ridges to be the result of tilt-block normal faul...

Mn doped ZnO nanocrystals were prepared by co-precipitation route sintered at 450 °C temperature. XRD results indicate that the samples having hexagonal (wurtzite) structure. From X-ray data it is found that the lattice parameters increase with increasing Mn concentration. The X-ray density decreases with increasing Mn concentration of Zn 1-x Mnx O nanocrystals. It indicates that the Mn...

Ridges and valleys are earth’s relief structures. They can have an imaging counterpart provided we model a digital image as a landscape by considering grey level values as height. These two dual entities have received comparatively little attention from the computer vision community with regard to others like edges or corners. In this paper we first propose a taxonomy or classification of the s...

A partial melt undergoing large scale deformation is shown to be unstable with respect to small scale redistribution of melt, provided the shear viscosity of the matrix depends on melt fraction. In the physically realistic case where melt "softens" the matrix, melt migrates along the direction parallel to the axis of minimum compressive stress and accumulates in "veins" (melt-rich lenses). The ...