Discontinuity Curves Research Articles

Extension of Alaskan structural trends beneath Bristol Bay, Bering Shelf, Alaska

Magnetic, gravity, and seismic profiling observations were systematically made 8 km apart over 63,960 km2 in southern Bristol Bay, Alaska. Magnetic and gravity anomalies show a sharp separation between low-frequency, subdued anomalies in the southern half of the area and high-frequency, large magnitude anomalies in the northern half. The strike of this discontinuity curves WSW-NW just north of Unimak Island (Alaska peninsula) and effectively outlines the westward extension of the Goodnews arch and the Bristol Bay basin structures as far as the Pribilof Islands. Seismic profiles suggest that the metamorphosed and intruded rocks of the Goodnews arch are fairly near the surface and are responsible for the high-frequency anomalies in the magnetic data. The data support the concept that the present Aleutian arch-Alaskan peninsula structure transects an older continental margin basin that formerly connected the shelf near Kodiak Island with that in the vicinity of the Pribilof Islands, Bering Sea.

Solutions to Nonlinear Hyperbolic Cauchy Problems Without Convexity Conditions

This paper is concerned with the existence of weak solutions to certain nonlinear hyperbolic Cauchy problems. A condition on the curves of discontinuity is used which guarantees uniqueness in the class of piecewise smooth weak solutions. The method of proof is geometric in nature and is constructive in the manner of A. Douglis and Wu Cho-Chün; that is, for certain types of initial data the method of characteristics is employed to construct piecewise smooth weak solutions. A limiting process is then used to obtain existence for bounded, measurable initial data. The solutions in some cases exhibit interesting, new phenomena. For example, a certain class of initial data having one jump gives rise to a solution having a curving contact discontinuity which does not enter the region of intersecting characteristics.

On the presence of crystallinity in hydrogenated polybutadienes

Crystallites in hydrogenated hydroxy terminated polybutadiene from polarized light examination, viscosity-temperature curve discontinuity and elastomer modulus-temperature curve

Positive-Ion Mobilities in Liquid Helium I

Seven distinct positive-ion mobilities have been found in liquid helium I at 4.2\ifmmode^\circ\else\textdegree\fi{}K. These mobilities correspond to the plateau regions of a mobility discontinuity curve similar to those discovered earlier in liquids helium II, argon, and nitrogen. A semiempirical equation is given which relates the mobilities corresponding to the plateau regions to a set of integers.

Solutions to nonlinear hyperbolic Cauchy problems without convexity conditions

This paper is concerned with the existence of weak solutions to certain nonlinear hyperbolic Cauchy problems. A condition on the curves of discontinuity is used which guarantees uniqueness in the class of piecewise smooth weak solutions. The method of proof is geometric in nature and is constructive in the manner of A. Doughs and Wu Cho-Chun; that is, for certain types of initial data the method of characteristics is employed to construct piecewise smooth weak solutions. A limiting process is then used to obtain existence for bounded, measurable initial data. The solutions in some cases exhibit interesting, new phenomena. For example, a certain class of initial data having one jump gives rise to a solution having a curving contact discontinuity which does not enter the region of intersecting characteristics. 1. Introduction. In this paper we consider existence of global weak solutions to the Cauchy problem

Propagation of One-Dimensional Stress Discontinuities in Homogeneous and Inhomogeneous Viscoelastic Media

The propagation of small amplitude stress discontinuities in linear viscoelastic media with differential stress-strain laws is considered. The theory of weak solutions is used to determine the curves of discontinuity and the jumps in the stress and the velocity and their successive derivatives on the discontinuity. A Taylor series expansion is then used to approximate the stress and the velocity behind and sufficiently near the discontinuity. These results are applied to study the propagation of longitudinal impact waves in semi-infinite and finite viscoelastic rods.