Can the reflection response of the subsurface be obtained without the need to place an active source at the surface? Using numerical modeling results based on one-way wavefields, we show that the reflection response of a 3-D inhomogeneous lossless medium can be reconstructed from the crosscorrelation of its transmission response at the surface. Depending on the type of subsurface noise sources,...

Census maps contain important socio-economic information regarding the population of a country. Computing these maps is critical given that policy makers often times make important decisions based upon such information. However, the compilation of census maps requires extensive resources and becomes highly expensive, especially for emerging economies with limited budgets. On the other hand, the...

Conditions are investigated which guarantee exactness for measurable maps on measure spaces. The main application is to certain piecewise continuous maps T on [0,1] for which 7"(0) > 1. We assume [0,1] can be broken into intervals on which T is continuous and convex and at the left end of these intervals T = 0 and dt/dx > 0. Such maps have an invariant absolutely continuous density which is exact.

The present paper studies mathematical models for representing, imaging, and analyzing polycrystalline materials. We introduce various techniques converting grain maps into diagram or tessellation representations that rely on constrained clustering. In particular, we show how to significantly accelerate the computation of generalized balanced power diagrams extend it allow optimization over all...

In this paper, we proposed a new segmentation-and-grouping framework for road map inference from sparsely-sampled GPS traces. First, we extended DBSCAN with the orientation constraint to partition the whole point set of traces to clusters representing road segments. Second, we proposed an adaptive k-means algorithm that the k value is determined by an angle threshold to reconstruct nearly strai...