Publications

Refine Results

(Filters Applied) Clear All

Gender-dependent phonetic refraction for speaker recognition

Published in:
Proc. IEEE Int. Conf. on Acoustics, Speech and Signal Processing, ICASSP, 13-17 May 2002, Vol. 1, pp. 149-152.

Summary

This paper describes improvement to an innovative high-performance speaker recognition system. Recent experiments showed that with sufficient training data phone strings from multiple languages are exceptional features for speaker recognition. The prototype phonetic speaker recognition system used phone sequences from six languages to produce an equal error rate of 11.5% on Switchboard-I audio files. The improved system described in this paper reduces the equal error rate to less than 4%. This is accomplished by incorporating gender-dependent phone models, pre-processing the speech files to remove cross-talk, and developing more sophisticated fusion techniques for the multi-language likelihood scores.
READ LESS

Summary

This paper describes improvement to an innovative high-performance speaker recognition system. Recent experiments showed that with sufficient training data phone strings from multiple languages are exceptional features for speaker recognition. The prototype phonetic speaker recognition system used phone sequences from six languages to produce an equal error rate of 11.5%...

READ MORE

Language identification using Gaussian mixture model tokenization

Published in:
Proc. IEEE Int. Conf., on Acoustics, Speech and Signal Processing, ICASSP, Vol. I, 13-17 May 2002, pp. I-757 - I-760.

Summary

Phone tokenization followed by n-gram language modeling has consistently provided good results for the task of language identification. In this paper, this technique is generalized by using Gaussian mixture models as the basis for tokenizing. Performance results are presented for a system employing a GMM tokenizer in conjunction with multiple language processing and score combination techniques. On the 1996 CallFriend LID evaluation set, a 12-way closed set error rate of 17% was obtained.
READ LESS

Summary

Phone tokenization followed by n-gram language modeling has consistently provided good results for the task of language identification. In this paper, this technique is generalized by using Gaussian mixture models as the basis for tokenizing. Performance results are presented for a system employing a GMM tokenizer in conjunction with multiple...

READ MORE

Interlingua-based English-Korean two-way speech translation of doctor-patient dialogues with CCLINC

Published in:
Machine Trans. Vol. 17, No. 3, 2002, pp. 213-243.

Summary

Development of a robust two-way real-time speech translation system exposes researchers and system developers to various challenges of machine translation (MT) and spoken language dialogues. The need for communicating in at least two different languages poses problems not present for a monolingual spoken language dialogue system, where no MT engine is embedded within the process flow. Integration of various component modules for real-time operation poses challenges not present for text translation. In this paper, we present the CCLINC (Common Coalition Language System at Lincoln Laboratory) English-Korean two-way speech translation system prototype trained on doctor-patient dialogues, which integrates various techniques to tackle the challenges of automatic real-time speech translation. Key features of the system include (i) language-independent meaning representation which preserves the hierarchical predicate-argument structure of an input utterance, providing a powerful mechanism for discourse understanding of utterances originating from different languages, word-sense disambiguation and generation of various word orders of many languages, (ii) adoption of the DARPA Communicator architecture, a plug-and-play distributed system architecture which facilitates integration of component modules and system operation in real time, and (iii) automatic acquisition of grammar rules and lexicons for easy porting of the system to different languages and domains. We describe these features in detail and present experimental results.
READ LESS

Summary

Development of a robust two-way real-time speech translation system exposes researchers and system developers to various challenges of machine translation (MT) and spoken language dialogues. The need for communicating in at least two different languages poses problems not present for a monolingual spoken language dialogue system, where no MT engine...

READ MORE

Detecting clusters of galaxies in the Sloan Digital Sky Survey. I. Monte Carlo comparison of cluster detection algorithms

Summary

We present a comparison of three cluster-finding algorithms from imaging data using Monte Carlo simulations of clusters embedded in a 25 deg(2) region of Sloan Digital Sky Survey (SDSS) imaging data: the matched filter (MF), the adaptive matched filter (AMF), and a color-magnitude filtered Voronoi tessellation technique (VTT). Among the two matched filters, we find that the MF is more efficient in detecting faint clusters, whereas the AMF evaluates the redshifts and richnesses more accurately, therefore suggesting a hybrid method (HMF) that combines the two. The HMF outperforms the VTT when using a background that is uniform, but it is more sensitive to the presence of a nonuniform galaxy background than is the VTT; this is due to the assumption of a uniform background in the HMF model. We thus find that for the detection thresholds we determine to be appropriate for the SDSS data, the performance of both algorithms are similar; we present the selection function for each method evaluated with these thresholds as a function of redshift and richness. For simulated clusters generated with a Schechter luminosity function (M(*r) = -21.5 and (a = -1.1), both algorithms are complete for Abell richness >~ clusters up to z ~0.4 for a sample magnitude limited to r = 21. While the cluster parameter evaluation shows a mild correlation with the local background density, the detection efficiency is not significantly affected by the background fluctuations, unlike previous shallower surveys.
READ LESS

Summary

We present a comparison of three cluster-finding algorithms from imaging data using Monte Carlo simulations of clusters embedded in a 25 deg(2) region of Sloan Digital Sky Survey (SDSS) imaging data: the matched filter (MF), the adaptive matched filter (AMF), and a color-magnitude filtered Voronoi tessellation technique (VTT). Among the...

READ MORE

Discrete optimization using decision-directed learning for distributed networked computing

Summary

Decision-directed learning (DDL) is an iterative discrete approach to finding a feasible solution for large-scale combinatorial optimization problems. DDL is capable of efficiently formulating a solution to network scheduling problems that involve load limiting device utilization, selecting parallel configurations for software applications and host hardware using a minimum set of resources, and meeting time-to-result performance requirements in a dynamic network environment. This paper quantifies the algorithms that constitute DDL and compares its performance to other popular combinatorial self-directed real-time networked resource configuration for dynamically building a mission specific signal-processor for real-time distributed and parallel applications.
READ LESS

Summary

Decision-directed learning (DDL) is an iterative discrete approach to finding a feasible solution for large-scale combinatorial optimization problems. DDL is capable of efficiently formulating a solution to network scheduling problems that involve load limiting device utilization, selecting parallel configurations for software applications and host hardware using a minimum set of...

READ MORE

The effect of personality type on the usage of a multimedia engineering education system

Author:
Published in:
32nd Annual ASEE/IEEE Frontiers in Education Conf., 6-9 November 2002, pp. T3A-7 - T3A-12.

Summary

Multimedia education has quickly entered our classrooms and offices providing tutorials and lessons on many different topics. The assumption that most people interact with these multimedia systems in similar ways can easily be made, but are these assumptions valid? What factors determine whether students will embrace computer-based multimedia-augmented learning? One factor may be the student's personality type. This paper explores the reasons why some students may enjoy learning using computer-based educational delivery systems while others may have absolutely no enthusiasm for this type of learning and how that enthusiasm may relate to the students' personality types.
READ LESS

Summary

Multimedia education has quickly entered our classrooms and offices providing tutorials and lessons on many different topics. The assumption that most people interact with these multimedia systems in similar ways can easily be made, but are these assumptions valid? What factors determine whether students will embrace computer-based multimedia-augmented learning? One...

READ MORE

PVL: An Object Oriented Software Library for Parallel Signal Processing (Abstract)

Published in:
CLUSTER '01, 2001 IEEE Int. Conf. on Cluster Computing, 8-11 October 2001, p. 74.

Summary

Real-time signal processing consumes the majority of the world's computing power Increasingly, programmable parallel microprocessors are used to address a wide variety of signal processing applications (e.g. scientific, video, wireless, medical, communication, encoding, radar, sonar and imaging). In programmable systems the major challenge is no longer hardware but software. Specifically, the key technical hurdle lies in mapping (i.e., placement and routing) of an algorithm onto a parallel computer in a general manner that preserves software portability. We have developed the Parallel Vector Library (PVL) to allow signal processing algorithms to be written using high level Matlab like constructs that are independent of the underlying parallel mapping. Programs written using PVL can be ported to a wide range of parallel computers without sacrificing performance. Furthermore, the mapping concepts in PVL provide the infrastructure for enabling new capabilities such as fault tolerance, dynamic scheduling and self-optimization. This presentation discusses PVL with particular emphasis on quantitative comparisons with standard parallel signal programming practices.
READ LESS

Summary

Real-time signal processing consumes the majority of the world's computing power Increasingly, programmable parallel microprocessors are used to address a wide variety of signal processing applications (e.g. scientific, video, wireless, medical, communication, encoding, radar, sonar and imaging). In programmable systems the major challenge is no longer hardware but software. Specifically...

READ MORE

Circuit-fed tile-approach configuration for millimeter-wave spatial power combining

Published in:
IEEE Trans. Microw. Theory Tech., Vol. 50, No. 1, Part 1, January 2002, pp. 17-21.

Summary

In this paper, a circuit-fed spatially combined transmitter array is described for operation at 44 GHz. The array contains 256 elements where each element consists of a monolithic-microwave integrated-circuit amplifier and a circularly polarized microchip patch antenna. The array is constructed using 16-element tile-approach subarrays. Each subarray is a two RF-level (three-dimensional) multichip module containing integrated microstrip patch antennas. The basic construction of the transmitter array resembles tile-approach phased arrays; however, the implementation has been tailored for the power-combining application. The peak performance at 43.5 GHz is equivalent isotropic radiated power of 40.6 dBW (11570 W), effective transmitted power (Peff) of 5.9 W, dc-to-RF efficiency of 7.3%, and system gain of 35 dB.
READ LESS

Summary

In this paper, a circuit-fed spatially combined transmitter array is described for operation at 44 GHz. The array contains 256 elements where each element consists of a monolithic-microwave integrated-circuit amplifier and a circularly polarized microchip patch antenna. The array is constructed using 16-element tile-approach subarrays. Each subarray is a two...

READ MORE

Analysis of delay causality at Newark International Airport

Published in:
4th USA/Europe Air Traffic Management R&D Seminar, 3-7 December 2001.

Summary

Determining causes of aviation delay is essential for formulating and evaluating approaches to reduce air traffic delays. An analysis was conducted of large weather-related delays at Newark International Airport (EWR), which, located in the heart of the congested northeast corridor of the United States, is an airport with a significant number of delays. Convective weather and reduced ceiling and visibility were found to be the leading contributors to large delays at EWR between September 1998 and August 2001. It was found that 41% of the cumulative arrival delay (delay relative to schedule) on days in this period averaging more than 15 minutes of delay per arrival occurred on days characterized by convective weather either within or at considerable distances from the New York terminal area. Of the remaining delays, 28% occurred on days characterized by low ceiling/visibility conditions, while 14% occurred on fair weather days with high surface winds, and 2% were caused by distant non-convective storms. Known causes other than weather accounted for 9% of the delays, and causes were unknown for 6%. When delay types (airborne, gate, taxi -out etc.) were categorized by the type of weather causing the delay, it was found that: (1) departure delays (gate + taxi-out) were much larger than arrival delays for thunderstorms in the NY terminal area and (2) taxi-out delays were the dominant type when delays were caused by distant convective weather. The fraction of total delay time explained by pre-planned Ground Delay Programs (GDP) rose sharply during 2000, accounting for over 40% of total the arrival delay that year, and then decreased slightly in 2001. On days with thunderstorms in the NY TRACON, arrival and departure delays were significantly higher during the year (2000) that GDPs were used most frequently.
READ LESS

Summary

Determining causes of aviation delay is essential for formulating and evaluating approaches to reduce air traffic delays. An analysis was conducted of large weather-related delays at Newark International Airport (EWR), which, located in the heart of the congested northeast corridor of the United States, is an airport with a significant...

READ MORE

Tactical convective weather decision support to complement "strategic" traffic flow management for convective weather

Author:
Published in:
46th Annual Air Traffic Control Association Conf. Proc., 4-8 November 2001, pp. 98-102.

Summary

Delay increases during the months of the year characterized by thunderstorms have been the principal cause of the dramatic delay growth in the US aviation system over the past 3 years, as shown in Figure 1. In 2000, the key new initiative for reducing these convective weather delays was "strategic" traffic flow management (TFM) through the Collaborative Convective Forecast Product (CCFP), the Strategic Planning Team, and Collaborative Routing (CR). This "strategic" approach has been quite successful in improving operations. However, in congested airspace, the inability to accurately forecast convective weather impacts requires a complementary tactical weather decision support capability. This paper describes terminal and enroute weather prediction systems plus traffic flow management and automation decision support tools to complement the strategic approach.
READ LESS

Summary

Delay increases during the months of the year characterized by thunderstorms have been the principal cause of the dramatic delay growth in the US aviation system over the past 3 years, as shown in Figure 1. In 2000, the key new initiative for reducing these convective weather delays was "strategic"...

READ MORE