Publications

Speaker recognition using high-level features has been a successful area of exploration. Features obtained from many different levels phones, words, prosodic events, etc. are used to characterize the speaker. A good modeling technique for these features is the support vector machine (SVM). SVMs model the n-gram frequencies from speaker utterances...

In this paper we describe experiments conducted during the development of a lattice-based PPRLM language identification system as part of the NIST 2005 language recognition evaluation campaign. In experiments following LRE05 the PPRLM-lattice sub-system presented here achieved a 30s/primary condition EER of 4.87%, making it the single best performing recognizer...

Recent work in forensic speaker recognition has introduced many new scoring methodologies. First, confidence scores (posterior probabilities) have become a useful method of presenting results to an analyst. The introduction of an objective measure of confidence score quality, the normalized cross entropy, has resulted in a systematic manner of evaluating...

In an era of significant federal government budget austerity for civil aviation operations, it has become essential to improve Air Traffic Control (ATC) productivity. This report summarizes the results of an exploratory field measurement program conducted during summer 2005 to assess ATC productivity benefits of the Corridor Integrated Weather System...

This paper describes the need for High Performance Computing (HPC) to facilitate the development and implementation of a nonlinear equalizer that is capable of mitigating and/or eliminating nonlinear distortion to extend the dynamic range of radar front-end receivers decades beyond the analog state-of-the-art. The search space for the optimal nonlinear...

A novel digital compensation technique is applied to linearize the frequency generation of a superwideband chirp. Ultra-linear, low-noise swept local oscillators (SLO) are critical to the two-tone dynamic range performance of compressive receivers. The proposed technique enables full software control of the chirp linearity, slope, and offset to allow automated...

The U.S. aviation system makes extensive use of national operational Doppler weather radar networks. These are critical for the detection and forecasting of thunderstorms and other hazardous weather phenomena, and they provide dense, continuously updated measurements of precipitation and wind fields as inputs to high-resolution numerical weather prediction models. This...

The U.S. air transportation system faces a continuously growing gap between the demand for air transportation and the capacity to meet that demand. Two key obstacles to bridging this gap are traffic delays due to en route severe-weather conditions and airport weather conditions. Lincoln Laboratory has been addressing these traffic...

Flight delays are now a major problem in the U.S. National Airspace System. A significant fraction of these delays are caused by reductions in en route capacity due to severe convective weather. The Corridor Integrated Weather System (CIWS) is a fully automated weather analysis and forecasting system designed to support...

Explicit integration of aviation weather forecasts with the National Airspace System (NAS) structure is needed to improve the development and execution of operationally effective weather impact mitigation plans and has become increasingly important due to NAS congestion and associated increases in delay. This article considers several contemporary weather-air traffic management...