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Machine-assisted language translation for U.S./RoK Combined Forces Command

January 1, 1999
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Journal Article
Author:
Young-Suk Lee
…
Published in:
Army RD&A Mag., November-December 1999, pp. 38-41.
Topic:
machine translation
R&D area:
R&D group:

Summary

The U.S. military must operate worldwide in a variety of international environments where many different languages are used. There is a critical need for translation, and there is a shortage of translators who can interpret military terminology specifically. One coalition environment where the need is particularly strong is in the Republic of Korea (RoK) where, although U.S. and RoK military personnel have been working together for many years, the language barrier still significantly reduces the speed and effectiveness of coalition command and control. This article describes the Massachusetts Institute of Technology (MIT) Lincoln Laboratory's work on automated, two-way, English/Korean translation for enhanced coalition communications. Our ultimate goal is to enhance multilingual communications by producing accurate translations across a number of languages. Therefore, we have chosen an interlingua-based approach to machine translation that is readily adaptable to multiple languages. In this approach, a natural language understanding system transforms the input into an intermediate meaning representation called Semantic Frame, which serves as a basis for generating output in multiple languages. To produce useful and effective translation systems in the short term, we have focused on limited military task domains and have configured our system as a machine-assisted translation system. This allows the human translator to confirm or edit the machine translation.
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Summary

The U.S. military must operate worldwide in a variety of international environments where many different languages are used. There is a critical need for translation, and there is a shortage of translators who can interpret military terminology specifically. One coalition environment where the need is particularly strong is in the...

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Machine-assisted language translation for U.S./RoK Combined Forces Command

Total global lightning inferred from Schumann resonance measurements

December 27, 1998
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Journal Article
Author:
S. J. Heckman
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Published in:
J. Geophys. Res., Vol. 103, No. D24, 27 December 1998, pp. 31,775-31,779.
Topic:
weather
R&D area:
R&D group:

Summary

Radiation with frequencies of 5-30 Hz is ducted between Earth's surface and ionosphere with little attenuation; at the lowest frequencies, waves travel several times around the Earth before losing most of their energy. Much of this radiation is produced by lightning. Here we assume that all of this radiation is produced by lightning, and attempt to invert the observed and electric and magnetic fields to infer global lightning activity. We show 10 days of inversions. For these 10 days, the inferred average rate of vertical charge transfer squared is only 1.7 105 (ten to the fifth) (Ckm)2/s Other studies suggest that the root mean square moment change of a flash is about 166 Coulomb kilometers. If we naively assume that each of these flashes is composed of four equally sized strokes, then we conclude that our entire observed signal could be produced by only 22 flashes per second.
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Summary

Radiation with frequencies of 5-30 Hz is ducted between Earth's surface and ionosphere with little attenuation; at the lowest frequencies, waves travel several times around the Earth before losing most of their energy. Much of this radiation is produced by lightning. Here we assume that all of this radiation is...

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Total global lightning inferred from Schumann resonance measurements

En route ATM decision support tool computer-human interface requirements development

December 1, 1998
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Conference Paper
Author:
Maria Picardi Kuffner
Published in:
2nd USA/Europe Air Traffic Management R&D Seminar, 1-4 December 1998.
Topic:
decision support
R&D area:
R&D group:

Summary

MIT Lincoln Laboratory (MIT/LL) is supporting the FAA-sponsored effort to specify Computer Human Interface (CHI) requirements for the En Route Air Traffic Management Decision Support Tools (ERATMDST) program. The ERATMDST CHI specification is the FAA's vehicle to ensure an operationally suitable user interface is provided for the DSTs (such as conflict probe) to support free flight. The initial draft of the ERATMDST CHI requirements was published in September 1998 and defines an initial CHI which incorporates elements of the NASA CTAS and the MITRE URET prototypes, an Operational Display and Input Development (ODID) display philosophy, and an outline of the end-state CHI. The information will be presented with a consistent, usable look and feel modeled on the advanced human-centered CHI developed by Eurocontrol. This paper describes a CHI Requirements Engineering Model (CREM) and presents preliminary test results of ODID-like display elements in the ERATMDST CHI with controller-in- the-loop simulations presented in terms of workload and response times.
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Summary

MIT Lincoln Laboratory (MIT/LL) is supporting the FAA-sponsored effort to specify Computer Human Interface (CHI) requirements for the En Route Air Traffic Management Decision Support Tools (ERATMDST) program. The ERATMDST CHI specification is the FAA's vehicle to ensure an operationally suitable user interface is provided for the DSTs (such as...

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En route ATM decision support tool computer-human interface requirements development

Blind clustering of speech utterances based on speaker and language characteristics

November 30, 1998
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Conference Paper
Author:
Douglas A. Reynolds
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Published in:
5th Int. Conf. Spoken Language Processing (ICSLP), 30 November - 4 December 1998.
Topic:
speaker recognition
R&D area:
R&D group:

Summary

Classical speaker and language recognition techniques can be applied to the classification of unknown utterances by computing the likelihoods of the utterances given a set of well trained target models. This paper addresses the problem of grouping unknown utterances when no information is available regarding the speaker or language classes or even the total number of classes. Approaches to blind message clustering are presented based on conventional hierarchical clustering techniques and an integrated cluster generation and selection method called the d* algorithm. Results are presented using message sets derived from the Switchboard and Callfriend corpora. Potential applications include automatic indexing of recorded speech corpora by speaker/language tags and automatic or semiautomatic selection of speaker specific speech utterances for speaker recognition adaptation.
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Summary

Classical speaker and language recognition techniques can be applied to the classification of unknown utterances by computing the likelihoods of the utterances given a set of well trained target models. This paper addresses the problem of grouping unknown utterances when no information is available regarding the speaker or language classes...

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Blind clustering of speech utterances based on speaker and language characteristics

Improving accent identification through knowledge of English syllable structure

November 30, 1998
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Conference Paper
Author:
Kay M. Berkling
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Published in:
5th Int. Conf. on Spoken Language Processing, ICSLP, 30 November - 4 December 1998.
Topic:
language recognition
R&D area:
R&D group:

Summary

This paper studies the structure of foreign-accented read English speech. A system for accent identification is constructed by combining linguistic theory with statistical analysis. Results demonstrate that the linguistic theory is reflected in real speech data and its application improves accent identification. The work discussed here combines and applies previous research in language identification based on phonemic features [1] with the analysis of the structure and function of the English language [2]. Working with phonemically hand-labelled data in three accented speaker groups of Australian English (Vietnamese, Lebanese, and native speakers), we show that accents of foreign speakers can be predicted and manifest themselves differently as a function of their position within the syllable. When applying this knowledge, English vs. Vietnamese accent identification improves from 86% to 93% (English vs. Lebanese improves from 78% to 84%). The described algorithm is also applied to automatically aligned phonemes.
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Summary

This paper studies the structure of foreign-accented read English speech. A system for accent identification is constructed by combining linguistic theory with statistical analysis. Results demonstrate that the linguistic theory is reflected in real speech data and its application improves accent identification. The work discussed here combines and applies previous...

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Improving accent identification through knowledge of English syllable structure

Airbus 320 performance during ATC-directed breakouts on final approach

November 20, 1998
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Project Report
Author:
Katherine de M. Hollister
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Published in:
MIT Lincoln Laboratory Report ATC-265
Topic:
air traffic control
R&D area:

Summary

An evaluation of Airbus 320 (A320) performance during ATC-directed breakouts was conducted in a two-part study during 1995. Phase 1 tested the combined effect of proposed ATC phraseology, pilot situational awareness training, and an A320-specific breakout procedure on performance. Pilot training included a briefing and viewing a videotape, but no simulator practice. Turn performance statistics from the Precision Runway Monitor Demonstration Program were used as the test criteria. Pilot preferences regarding procedures and the training material were also elicited. Three conclusions were: (1) breakout performance given the tested combination of pilot training and proposed ATC phraseology did meet the test criteria; (2) breakout performance given existing procedures did not meet the test criteria; and (3) the tested breakout procedure should be refined because it conflicted with other cockpit procedures and increased the transition time to a positive climb rate. Based on the results of this study, it is recommended that a combination of pilot situational awareness training, A320 breakout procedure, and modified ATC breakout phraseology equivalent to that tested in Phase 2 be employed for simultaneous parallel approach operations in instrument meteorological conditions.
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Summary

An evaluation of Airbus 320 (A320) performance during ATC-directed breakouts was conducted in a two-part study during 1995. Phase 1 tested the combined effect of proposed ATC phraseology, pilot situational awareness training, and an A320-specific breakout procedure on performance. Pilot training included a briefing and viewing a videotape, but no...

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Airbus 320 performance during ATC-directed breakouts on final approach

Sheep, goats, lambs and wolves: a statistical analysis of speaker performance in the NIST 1998 speaker recognition evaluation

November 1, 1998
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Conference Paper
Author:
George R. Doddington
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Published in:
NIST 1998 Speaker Recognition Evaluation, November 1998.
Topic:
speaker recognition
R&D area:
R&D group:

Summary

Performance variability in speech and speaker recognition systems can be attributed to many factors. One major factor, which is often acknowledged but seldom analyzed, is inherent differences in the recognizability of different speakers. In speaker recognition systems such differences are characterized by the use of animal names for different types of speakers, including sheep, goats, lambs and wolves, depending on their behavior with respect to automatic recognition systems. In this paper we propose statistical tests for the existence of these animals and apply these tests to hunt for such animals using results from the 1998 NIST speaker recognition evaluation.
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Summary

Performance variability in speech and speaker recognition systems can be attributed to many factors. One major factor, which is often acknowledged but seldom analyzed, is inherent differences in the recognizability of different speakers. In speaker recognition systems such differences are characterized by the use of animal names for different types...

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Sheep, goats, lambs and wolves: a statistical analysis of speaker performance in the NIST 1998 speaker recognition evaluation

A dual-band circularly polarized aperture-coupled stacked microstrip antenna for global positioning satellite

November 1, 1998
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Journal Article
Author:
D. M. Pozar
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Published in:
IEEE Trans. Antennas Propag., Vol. 45, No. 11, November 1997, pp. 1618-25.
Topic:
antennas
R&D area:
R&D group:

Summary

This paper describes the design and testing of an aperture-coupled circularly polarized antenna for global positioning satellite (GPS) applications. The antenna operates at both the L1 and L2 frequencies of 1575 and 1227 MHz, which is required for differential GPS systems in order to provide maximum positioning accuracy. Electrical performance, low-profile, and cost were equally important requirements for this antenna. The design procedure is discussed, and measured results are presented. Results from a manufacturing sensitivity analysis are also included.
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Summary

This paper describes the design and testing of an aperture-coupled circularly polarized antenna for global positioning satellite (GPS) applications. The antenna operates at both the L1 and L2 frequencies of 1575 and 1227 MHz, which is required for differential GPS systems in order to provide maximum positioning accuracy. Electrical performance...

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A dual-band circularly polarized aperture-coupled stacked microstrip antenna for global positioning satellite

Techniques for improved reception of 1090 MHz ADS-B signals

October 31, 1998
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Conference Paper
Author:
William H. Harman III
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Published in:
17th DASC: Proc. of the 17th. Digital Avionics Systems Conf., 31 October - 7 November 1998, Vol. 2, pp. G25-1 - G25-9.
Topic:
surveillance
R&D area:
R&D group:

Summary

The recent development of ADS-B (Automatic Dependent Surveillance-Broadcast) is based on the use of the Mode S transponders now carried by all air carrier and commuter aircraft. ADS-B aircraft broadcast aircraft positions, identity, and other information via semi-random Mode S transponder squitters. Other aircraft or ground facilities receive the squitters and the associated position and status. Squitter reception includes the detection of the Mode S 1090 MHz waveform preamble, declaration of the bit and confidence values, error detection, and (if necessary) error correction. The current techniques for squitter reception are based upon methods developed for use in Mode S narrow-beam interrogators and for ACAS. In both of these applications, the rate of Mode NC fruit that is stronger than the Mode S waveform is relatively low, nominally less than 4,000 fruit per second. Extended squitter applications now include long range (up to 100 nmi) air-air surveillance in support of free flight. This type of surveillance is sometimes referred to as Cockpit Display of Traffic Information (CDTI). In high density environments, it is possible to operate with fruit rates of 40,000 fruit per second and higher. Operation of extended squitter in very high ModeNC fruit environments has led to the need to re-evaluate squitter reception techniques to determine if improved performance is achievable. The purpose of this paper is to provide a summary of work in progress to investigate improved squitter reception techniques. Elements of improved squitter reception being investigated include (1) the use of amplitude to improve bit and confidence declaration accuracy, (2) more capable error correction algorithms, and (3) more selective preamble detection approaches.
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Summary

The recent development of ADS-B (Automatic Dependent Surveillance-Broadcast) is based on the use of the Mode S transponders now carried by all air carrier and commuter aircraft. ADS-B aircraft broadcast aircraft positions, identity, and other information via semi-random Mode S transponder squitters. Other aircraft or ground facilities receive the squitters...

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Techniques for improved reception of 1090 MHz ADS-B signals

Vulnerabilities of reliable multicast protocols

October 21, 1998
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Conference Paper
Author:
Thomas M. Parks
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Published in:
IEEE MILCOM '98, Vol. 3, 21 October 1998, pp. 934-938.
Topic:
cryptography
R&D area:
R&D group:

Summary

We examine vulnerabilities of several reliable multicast protocols. The various mechanisms employed by these protocols to provide reliability can present vulnerabilities. We show how some of these vulnerabilities can be exploited in denial-of-service attacks, and discuss potential mechanisms for withstanding such attacks.
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Summary

We examine vulnerabilities of several reliable multicast protocols. The various mechanisms employed by these protocols to provide reliability can present vulnerabilities. We show how some of these vulnerabilities can be exploited in denial-of-service attacks, and discuss potential mechanisms for withstanding such attacks.

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Vulnerabilities of reliable multicast protocols
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