Chris L. Pettit

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A patient with primary extranodal lymphoma arising in the trachea presented with severe upper airway obstruction. The tumor was localized at presentation. The patient has remained disease-free for 12 months following surgical resection and local radiation treatment. The tumor had distinctive morphologic features characteristic of low-grade lymphomas of(More)
Outdoor sound propagation predictions are compromised by uncertainty and error in the atmosphere and terrain representations, and sometimes also by simplified or incorrect physics. A model's predictive power, i.e., its accurate representation of the sound propagation, cannot be assessed without first quantifying the ensemble sound pressure variability and(More)
The Environmental Awareness for Sensor and Emitter Employment (EASEE) software is designed to help in surveillance planning by predicting detection performance of sensors and optimizing sensor selection and placement for intrusion detection around any controlled area, including power plants, dams, borders, prisons, military bases, combat outposts, etc. By(More)
The accuracy of outdoor sound propagation predictions is often limited by imperfect knowledge of the atmospheric and ground properties, and random environmental variations such as turbulence. This article describes the impact of such uncertainties, and how they can be efficiently addressed and quantified with stochastic sampling techniques such as Monte(More)
Many outdoor sound propagation models exist, ranging from highly complex physics-based simulations to simplified engineering calculations, and more recently, highly flexible statistical learning methods. Several engineering and statistical learning models are evaluated by using a particular physics-based model, namely, a Crank-Nicholson parabolic equation(More)