A spatio-temporal drought analysis for the Midwestern US

15 Jun 2009 | Publications | Contributor(s): Rao S Govindaraju, Dev Niyogi

Droughts are prolonged abnormalities of moisture deficits that vary widely across temporal and spatial scales. Many hydrometeorologic variables are used to monitor the status of a drought. However, because of the dependence structure between all affecting variables under various temporal windows, …

A copula-based joint deficit index for droughts

31 Mar 2010 | Publications | Contributor(s): Rao S Govindaraju

Current drought information is based on indices that do not capture the joint behaviors of hydrologic variables. To address this limitation, the potential of copulas in characterizing droughts from multiple variables is explored in this study. Starting from the standardized index (SI) algorithm, a …

Urban Ecosystem Design

07 Jun 2011 | Publications | Contributor(s): Daniel Gerardo Aliaga

We address the open problem of spatial distribution of vegetation in urban environments by introducing a user-guided simulation and procedural system for integrating plants into the interactive design process of 3D urban models. Our approach uses as input 3D geometry of an urban layout from which …

A Web-Based Interface for SWAT Modeling on the TeraGrid

06 Jun 2011 | Publications | Contributor(s): Lan Zhao, Carol Song, Indrajeet Chaubey, Rao S Govindaraju

The Soil and Water Assessment Tool (SWAT) is a river basin scale model developed by the USDA Agricultural Research Service (ARS). It is widely used by researchers in various scientific domains to study the impact of land management practices on water quantity, sediment, and water quality in large …

Delivering Real-time Satellite Data to a Broader Audience

06 Jun 2011 | Publications | Contributor(s): Lan Zhao, Carol Song, Larry Biehl

This paper presents our work of enhancing the existing cyberinfrastructure using Web 2.0 technologies for delivering real time satellite data to a broader audience. As a resource provider on the TeraGrid, Purdue University hosts several data collections for earth and environmental research, …

A TeraGrid Science Gateway for Studying Hydrological Extremes using a Land Data Assimilation System

06 Jun 2011 | Publications | Contributor(s): Dev Niyogi, Lan Zhao, Carol Song, Rao S Govindaraju

A TeraGrid enabled science gateway to study surface hydrology is under development at Purdue University. Such a gateway is needed for class room and graduate research as well as for developing a multidisciplinary framework that integrates environmental observatories and tools for drought/flood …

Evaluating a New Deposition Velocity Module in the Noah Land-Surface Model

13 Jun 2011 | Publications | Contributor(s): Dev Niyogi

The community Noah land-surface model (Noah LSM) has been modified to couple with a photosynthesis-transpiration scheme (GEM) to estimate the deposition veloc- ity (Vd ) for air quality studies. This new capability of the Noah-GEM model was tested in a point version of the National Center for …

Modeling the Appearance and Behavior of Urban Spaces

16 Jun 2011 | Publications | Contributor(s): Daniel Gerardo Aliaga

Urban spaces consist of a complex collection of buildings, parcels, blocks and neighborhoods interconnected by streets. Accurately modeling both the appearance and the behavior of dense urban spaces is a significant challenge. The recent surge in urban data and its availability via the Internet has …

Interactive Design of Urban Spaces using Geometrical and Behavioral Modeling

14 Jun 2011 | Publications | Contributor(s): Daniel Gerardo Aliaga

The main contribution of our work is in closing the loop between behavioral and geometrical modeling of cities. Editing of urban design variables is performed intuitively and visually using a graphical user interface. Any design variable can be constrained or changed. The design process uses an …

Building Reconstruction using Manhattan-World Grammars

14 Jun 2011 | Publications | Contributor(s): Daniel Gerardo Aliaga

We present a passive computer vision method that exploits existing mapping and navigation databases in order to automatically create 3D building models. Our method defines a grammar for representing changes in building geometry that approximately follow the Manhattan-world assumption which states …