We investigate the capability of Time Reversal Mirror (TRM) algorithm to image local acoustic sources (<3.5 km) associated with complex, sustained volcanic eruptions. Accurate source localization for volcano infrasound (low-frequency acoustic waves) is often challenging due to pronounced volcanic topography and emergent arrivals of infrasound signals. While the accuracy of the conventional app…

The rise of new free trade agreements in the 1990s and early 2000s altered the dynamic of the World Trade Organization (WTO) as the arbiter of world commerce forever. Moreover, WTO negotiating rounds over the past decade have been beset with irreconcilable objectives among WTO members, with emerging market members fundamentally opposed to opening their markets to exports from advanced count…

In 2003, Kedlaya gave an algorithm to compute the zeta function associated to a hyperelliptic curve over a finite field, by computing the rigid cohomology of the curve. Edixhoven remarked that it is actually possible to compute the crystalline cohomology of the curve, which is a lattice in the rigid cohomology. Following a method of Wach, we explain how to use this lattice to compute the (b…

We present an extension of the nodal discontinuous Galerkin method for elastic wave propagation to high interpolation orders and arbitrary heterogeneous media. The high-order lagrangian interpolation is based on a set of nodes with excellent interpolation properties in the standard triangular element. In order to take into account highly variable geological media, another set of suitable quadra…

Tahun Terbit

2009

Tahun Terbit

2009

The North Atlantic right whale, Eubalaena glacialis (NARW), a critically endangered species that has been under intensive study for nearly four decades, provides an excellent case study for applying modern methods of conservation physiology to large whales. By combining long-term sighting histories of known individuals with physiological data from newer techniques (e.g., body condition estimat…

Green tides are large growths or accumulations of green seaweeds that have been increasing in magnitude and frequency around the world. Because green tides consist of vast biomasses of algae in a limited area and are often seasonal or episodic, they go through periods of rapid growth in which they take up large amounts of nutrients and dissolved gases and generate bioactive natural products tha…

The long and complex history of southern Africa makes it a geological nexus for understanding how crust forms, evolves and survives plate tectonic processes over billions of years. The goal of this study is to characterize the crustal thickness, composition, and Mohoimpedance contrasts across the Kaapvaal and Zimbabwe Cratons and surrounding mobile belts, which range in age from Archean to Pala…

This paper estimates the long-run impact of a large income shock based on regional variations in the 1987�89 locust plague in Mali. We take comprehensive population census data to construct birth cohorts of individuals and compare those born and living in the years and villages affected by locust plagues with other cohorts. We find a clear, strong impact on the educational outcomes of …