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The effect of text difficulty on machine translation performance -- a pilot study with ILR-related texts in Spanish, Farsi, Arabic, Russian and Korean

Published in:
4th Int. Conf. on Language Resources and Evaluation, LREC, 26-28 May 2004.

Summary

We report on initial experiments that examine the relationship between automated measures of machine translation performance (Doddington, 2003, and Papineni et al. 2001) and the Interagency Language Roundtable (ILR) scale of language proficiency/difficulty that has been in standard use for U.S. government language training and assessment for the past several decades (Child, Clifford and Lowe 1993). The main question we ask is how technology-oriented measures of MT performance relate to the ILR difficulty levels, where we understand that a linguist with ILR proficiency level N is expected to be able to understand a document rated at level N, but to have increasing difficulty with documents at higher levels. In this paper, we find that some key aspects of MT performance track with ILR difficulty levels, primarily for MT output whose quality is good enough to be readable by human readers.
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Summary

We report on initial experiments that examine the relationship between automated measures of machine translation performance (Doddington, 2003, and Papineni et al. 2001) and the Interagency Language Roundtable (ILR) scale of language proficiency/difficulty that has been in standard use for U.S. government language training and assessment for the past several...

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Conversational telephone speech corpus collection for the NIST speaker recognition evaluation 2004

Published in:
Proc. Language Resource Evaluation Conf., LREC, 24-30 May 2004, pp. 587-590.

Summary

This paper discusses some of the factors that should be considered when designing a speech corpus collection to be used for text independent speaker recognition evaluation. The factors include telephone handset type, telephone transmission type, language, and (non-telephone) microphone type. The paper describes the design of the new corpus collection being undertaken by the Linguistic Data Consortium (LDC) to support the 2004 and subsequent NIST speech recognition evaluations. Some preliminary information on the resulting 2004 evaluation test set is offered.
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Summary

This paper discusses some of the factors that should be considered when designing a speech corpus collection to be used for text independent speaker recognition evaluation. The factors include telephone handset type, telephone transmission type, language, and (non-telephone) microphone type. The paper describes the design of the new corpus collection...

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The mixer corpus of multilingual, multichannel speaker recognition data

Published in:
Proc. Language Resource Evaluation Conf., LREC, 24-30 May 2004, pp. 627-630.

Summary

This paper describes efforts to create corpora to support and evaluate systems that perform speaker recognition where channel and language may vary. Beyond the ongoing evaluation of speaker recognition systems, these corpora are aimed at the bilingual and cross channel dimensions. We report on specific data collection efforts at the Linguistic Data Consortium and the research ongoing at the US Federal Bureau of Investigation and MIT Lincoln Laboratories. We cover the design and requirements, the collections and final properties of the corpus integrating discussions of the data preparation, research, technology development and evaluation on a grand scale.
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Summary

This paper describes efforts to create corpora to support and evaluate systems that perform speaker recognition where channel and language may vary. Beyond the ongoing evaluation of speaker recognition systems, these corpora are aimed at the bilingual and cross channel dimensions. We report on specific data collection efforts at the...

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Corridor integrated weather system operation benefits 2002-2003 : initial estimates of convective weather delay reduction : executive summary

Published in:
MIT Lincoln Laboratory Report ATC-313-1

Summary

The Corridor Integrated Weather System (CIWS) seeks to improve safety and reduce delay by providing accurate, automated, rapidly updated information on storm locations and echo tops along with two-hour high-resolution animated growth and decay convective storm forecasts. An operational benefits assessment was conducted using on-site observations of CIWS usage at major en route control centers in the Northeast and Great Lakes corridors and the Air Traffic Control Systems Command Center (ATCSCC) during six multi-day periods in 2003. (Not complete).
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Summary

The Corridor Integrated Weather System (CIWS) seeks to improve safety and reduce delay by providing accurate, automated, rapidly updated information on storm locations and echo tops along with two-hour high-resolution animated growth and decay convective storm forecasts. An operational benefits assessment was conducted using on-site observations of CIWS usage at...

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High-level speaker verification with support vector machines

Published in:
Proc. IEEE Int. Conf. on Acoustics, Speech and Signal Processing, Vol. 1, ICASSP, 17-21 May 2004, pp. I-73 - I-76.

Summary

Recently, high-level features such as word idiolect, pronunciation, phone usage, prosody, etc., have been successfully used in speaker verification. The benefit of these features was demonstrated in the NIST extended data task for speaker verification; with enough conversational data, a recognition system can become familiar with a speaker and achieve excellent accuracy. Typically, high-level-feature recognition systems produce a sequence of symbols from the acoustic signal and then perform recognition using the frequency and co-occurrence of symbols. We propose the use of support vector machines for performing the speaker verification task from these symbol frequencies. Support vector machines have been applied to text classification problems with much success. A potential difficulty in applying these methods is that standard text classification methods tend to smooth frequencies which could potentially degrade speaker verification. We derive a new kernel based upon standard log likelihood ratio scoring to address limitations of text classification methods. We show that our methods achieve significant gains over standard methods for processing high-level features.
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Summary

Recently, high-level features such as word idiolect, pronunciation, phone usage, prosody, etc., have been successfully used in speaker verification. The benefit of these features was demonstrated in the NIST extended data task for speaker verification; with enough conversational data, a recognition system can become familiar with a speaker and achieve...

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Multisensor MELPE using parameter substitution

Published in:
Proc. IEEE Int. Conf. on Acoustics, Speech and Signal Processing, ICASSP, Vol. 1, 17-21 May 2004, pp. I-477 - I-480.

Summary

The estimation of speech parameters and the intelligibility of speech transmitted through low-rate coders, such as MELP, are severely degraded when there are high levels of acoustic noise in the speaking environment. The application of nonacoustic and nontraditional sensors, which are less sensitive to acoustic noise than the standard microphone, is being investigated as a means to address this problem. Sensors being investigated include the General Electromagnetic Motion Sensor (GEMS) and the Physiological Microphone (P-mic). As an initial effort in this direction, a multisensor MELPe coder using parameter substitution has been developed, where pitch and voicing parameters are obtained from GEMS and PMic sensors, respectively, and the remaining parameters are obtained as usual from a standard acoustic microphone. This parameter substitution technique is shown to produce significant and promising DRT intelligibility improvements over the standard 2400 bps MELPe coder in several high-noise military environments. Further work is in progress aimed at utilizing the nontraditional sensors for additional intelligibility improvements and for more effective lower rate coding in noise.
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Summary

The estimation of speech parameters and the intelligibility of speech transmitted through low-rate coders, such as MELP, are severely degraded when there are high levels of acoustic noise in the speaking environment. The application of nonacoustic and nontraditional sensors, which are less sensitive to acoustic noise than the standard microphone...

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Modifications to ACAS safety study methods for remotely piloted vehicles (RPV)

Author:
Published in:
Int. Civil Aviation Organization Surveillance and Conflict Resolution Systems Panel Working Group, 3-7 May 2004.

Summary

Estimating the relative safety of a Remotely Piloted Vehicle (RPV) equipped with ACAS will require several extensions to the methods developed in previous ACAS studies. This paper outlines several of these redesign issues. First, it may be necessary to compute the probability that an RPV will experience a critical encounter relative to that for a conventional aircraft. Performing a safety study on only the incremental impact of equipping an RPV with ACAS would circumvent this need. Additionally, methods are proposed to adapt existing encounter models to better represent the likely characteristics of encounters with RPVs. Finally, modifications to the level of detail included in dynamic simulations and fault trees are discussed. It is proposed to shift all dynamic elements out of the fault tree and into a new more complex Monte Carlo simulation.
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Summary

Estimating the relative safety of a Remotely Piloted Vehicle (RPV) equipped with ACAS will require several extensions to the methods developed in previous ACAS studies. This paper outlines several of these redesign issues. First, it may be necessary to compute the probability that an RPV will experience a critical encounter...

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Adaptive doppler filtering applied to modern air traffic control radars

Published in:
Proc. of the IEEE 2004 Radar Conf., 26-29 April 2004, pp. 242-248.

Summary

This paper presents an analysis of the Doppler processing technology currently in use in the nation's terminal airport surveillance radars, and examines possibilities for performance improvement, particularly in the presence of moving clutter. The research focuses on five- and eight-pulse waveform methodologies and their respective detection capabilities given clearly defined rain clutter scenarios. Performance with fixed coefficient filters similar to those used in the existing radars is calculated, followed by performance using an adaptive Doppler filtering technique. Performance is quantified in terms of signal-to-interference ratio at the output of the Doppler filters and resultant probability of detection given a specified probability of false alarm. The results will show that a substantial improvement in detection in the vicinity of rain clutter is realized for both the five- and eight-pulse waveforms when using the adaptive coefficient Doppler filters as compared to the performance observed with the fixed coefficient filters. For constant filter weights, the eight-pulse Doppler filters give significantly better performance in most diverse rain clutter than the five-pulse Doppler filters.
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Summary

This paper presents an analysis of the Doppler processing technology currently in use in the nation's terminal airport surveillance radars, and examines possibilities for performance improvement, particularly in the presence of moving clutter. The research focuses on five- and eight-pulse waveform methodologies and their respective detection capabilities given clearly defined...

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Power-law scattering models and nonlinear parametric estimation for super-resolution radar

Published in:
MIT Lincoln Laboratory Report TR-1095

Summary

This paper introduces a direct solution of the frequency-dependent, GTD-based, scatterer-model parameters leading towards a new modern spectral-estimation technique to be used for enhanced, super-resolution radar analysis. The overcomplete nature of the full GTD scatterer-model basis (positive and negative half-integer power laws) is recognized and overcome by introducing the vector-channel method, well known from communication theory. This physically motivated discretemodel- based analysis eliminates the need for computationally intensive and potentially nonconvergent local optimization procedures. Each scatterer is assigned a half-integer power law that identifies its cross-section frequency dependence and hence restricts the possible underlying physical feature geometries. This analysis opens the possibility for vector-attribute-based feature processing for target recognition that offers the potential for significant improvement in target identification performance.
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Summary

This paper introduces a direct solution of the frequency-dependent, GTD-based, scatterer-model parameters leading towards a new modern spectral-estimation technique to be used for enhanced, super-resolution radar analysis. The overcomplete nature of the full GTD scatterer-model basis (positive and negative half-integer power laws) is recognized and overcome by introducing the vector-channel...

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A method for correcting Fourier transform spectrometer (FTS) dynamic alignment errors

Published in:
SPIE Vol. 5425, Algorithms and Technologies for Multispectral, Hyperspectral, and Ultraspectral Imagery X, 12-15 April 2004, pp. 443-455.

Summary

The Cross-track Infrared Sounder (CrIS), like most Fourier Transform spectrometers, can be sensitive to mechanical disturbances during the time spectral data is collected. The Michelson interferometer within the spectrometer modulates input radiation at a frequency equal to the product of the wavenumber of the radiation and the constant optical path difference (OPD) velocity associated with the moving mirror. The modulation efficiency depends on the angular alignment of the two wavefronts exiting the spectrometer. Mechanical disturbances can cause errors in the alignment of the wavefronts which manifest as noise in the spectrum. To mitigate these affects CrIS will employ a laser to monitor alignment and dynamically correct the errors. Additionally, a vibration isolation system will damp disturbances imparted to the sensor from the spacecraft. Despite these efforts, residual noise may remain under certain conditions. Through simulation of CrIS data, we demonstrated an algorithmic technique to correct residual dynamic alignment errors. The technique requires only the time-dependent wavefront angle, sampled coincidentally with the interferogram, and the second derivative of the erroneous interferogram as inputs to compute the correction. The technique can function with raw interferograms on board the spacecraft, or with decimated interferograms on the ground. We were able to reduce the dynamic alignment noise by approximately a factor of ten in both cases. Performing the correction on the ground would require an increase in data rate of 1-2% over what is currently planned, in the form of 8-bit digitized angle data.
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Summary

The Cross-track Infrared Sounder (CrIS), like most Fourier Transform spectrometers, can be sensitive to mechanical disturbances during the time spectral data is collected. The Michelson interferometer within the spectrometer modulates input radiation at a frequency equal to the product of the wavenumber of the radiation and the constant optical path...

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