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N. Gupta

Publications and source records attributed to N. Gupta.

5 recordsLinked to original sources
USGS2006

Managing large-scale workflow execution from resource provisioning to provenance tracking: The CyberShake example

This paper discusses the process of building an environment where large-scale, complex, scientific analysis can be scheduled onto a heterogeneous collection of computational and storage resources. The example application is the Southern California Earthquake Center (SCEC) CyberShake project, an analysis designed to compute probabilistic seismic hazard curves for sites in the Los Angeles area. We explain which software tools were used to build to the system, describe their functionality and interactions. We show the results of running the CyberShake analysis that included over 250,000 jobs using resources available through SCEC and the TeraGrid. ?? 2006 IEEE.

Conference Paper↗
USGS2005

Loss estimates for a Puente Hills blind-thrust earthquake in Los Angeles, California

Based on OpenSHA and HAZUS-MH, we present loss estimates for an earthquake rupture on the recently identified Puente Hills blind-thrust fault beneath Los Angeles. Given a range of possible magnitudes and ground motion models, and presuming a full fault rupture, we estimate the total economic loss to be between $82 and $252 billion. This range is not only considerably higher than a previous estimate of $69 billion, but also implies the event would be the costliest disaster in U.S. history. The analysis has also provided the following predictions: 3,000-18,000 fatalities, 142,000-735,000 displaced households, 42,000-211,000 in need of short-term public shelter, and 30,000-99,000 tons of debris generated. Finally, we show that the choice of ground motion model can be more influential than the earthquake magnitude, and that reducing this epistemic uncertainty (e.g., via model improvement and/or rejection) could reduce the uncertainty of the loss estimates by up to a factor of two. We note that a full Puente Hills fault rupture is a rare event (once every ???3,000 years), and that other seismic sources pose significant risk as well. ?? 2005, Earthquake Engineering Research Institute.

Earthquake Spectra↗
USGS2005

Hazard calculations for the WGCEP-2002 earthquake forecast using OpenSHA and distributed object technologies

We present seismic-hazard calculations for what is arguably the most sophisticated earthquake forecast ever developed—the model by the 2002 Working Group on California Earthquake Probabilities (2003), or WGCEP-2002 as referred to hereafter. These calculations have been made possible by developments in both OpenSHA ( Field et al. , 2003 ) and the Information Technology Research (ITR) Collaboration of the Southern California Earthquake Center (SCEC) ( Jordan et al. , 2003 ). In particular, we demonstrate the use of a freely available, platform-independent, and graphical-user-interface-based application for computing hazard curves. This application utilizes distributed-object technologies, meaning the code running on the client's computer communicates over the Internet with code hosted elsewhere on server computers. This interoperability, which is invisible to the user, makes the application fast and executable without heavy installation requirements. Instructions on how to reproduce the calculations presented here are available under “Publications” at the Web site http://www.OpenSHA.org/ .

Seismological Research Letters↗