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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

May 26, 2004
  |
Conference Paper
Author:
Ray Clifford
…
Published in:
4th Int. Conf. on Language Resources and Evaluation, LREC, 26-28 May 2004.
Topic:
machine translation
R&D area:
R&D group:

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

Multisensor MELPE using parameter substitution

May 17, 2004
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Conference Paper
Author:
Kevin Brady
…
Published in:
Proc. IEEE Int. Conf. on Acoustics, Speech and Signal Processing, ICASSP, Vol. 1, 17-21 May 2004, pp. I-477 - I-480.
Topic:
speaker recognition
R&D area:
R&D group:

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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Multisensor MELPE using parameter substitution

Exploiting nonacoustic sensors for speech enhancement

December 11, 2003
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Conference Paper
Author:
Thomas F. Quatieri
…
Published in:
Proc. Workshop on Multimodal User Authentication, 11-12 December 2003, pp. 66-73.
Topic:
speaker recognition
R&D area:
R&D group:

Summary

Nonacoustic sensors such as the general electromagnetic motion sensor (GEMS), the physiological microphone (P-mic), and the electroglottograph (EGG) offer multimodal approaches to speech processing and speaker and speech recognition. These sensors provide measurements of functions of the glottal excitation and, more generally, of the vocal tract articulator movements that are relatively immune to acoustic disturbances and can supplement the acoustic speech waveform. This paper describes an approach to speech enhancement that exploits these nonacoustic sensors according to their capability in representing specific speech characteristics in different frequency bands. Frequency-domain sensor phase, as well as magnitude, is found to contribute to signal enhancement. Preliminary testing involves the time-synchronous multi-sensor DARPA Advanced Speech Encoding Pilot Speech Corpus collected in a variety of harsh acoustic noise environments. The enhancement approach is illustrated with examples that indicate its applicability as a pre-processor to low-rate vocoding and speaker authentication, and for enhanced listening from degraded speech.
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Summary

Nonacoustic sensors such as the general electromagnetic motion sensor (GEMS), the physiological microphone (P-mic), and the electroglottograph (EGG) offer multimodal approaches to speech processing and speaker and speech recognition. These sensors provide measurements of functions of the glottal excitation and, more generally, of the vocal tract articulator movements that are...

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Exploiting nonacoustic sensors for speech enhancement

Multimodal speaker authentication using nonacuostic sensors

December 11, 2003
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Conference Paper
Author:
William M. Campbell
…
Published in:
Proc. Workshop on Multimodal User Authentication, 11-12 December 2003, pp. 215-222.
Topic:
speech enhancement
R&D area:
R&D group:

Summary

Many nonacoustic sensors are now available to augment user authentication. Devices such as the GEMS (glottal electromagnetic micro-power sensor), the EGG (electroglottograph), and the P-mic (physiological mic) all have distinct methods of measuring physical processes associated with speech production. A potential exciting aspect of the application of these sensors is that they are less influenced by acoustic noise than a microphone. A drawback of having many sensors available is the need to develop features and classification technologies appropriate to each sensor. We therefore learn feature extraction based on data. State of the art classification with Gaussian Mixture Models and Support Vector Machines is then applied for multimodal authentication. We apply our techniques to two databases--the Lawrence Livermore GEMS corpus and the DARPA Advanced Speech Encoding Pilot corpus. We show the potential of nonacoustic sensors to increase authentication accuracy in realistic situations.
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Summary

Many nonacoustic sensors are now available to augment user authentication. Devices such as the GEMS (glottal electromagnetic micro-power sensor), the EGG (electroglottograph), and the P-mic (physiological mic) all have distinct methods of measuring physical processes associated with speech production. A potential exciting aspect of the application of these sensors is...

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Multimodal speaker authentication using nonacuostic sensors

Biometrically enhanced software-defined radios

November 17, 2003
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Conference Paper
Author:
Joseph P. Campbell Jr
…
Published in:
Software Defined Radio Tech. Conf., SDR, 17-19 November 2003.
Topic:
speaker recognition
R&D area:
R&D group:

Summary

Software-defined radios and cognitive radios offer tremendous promise, while having great need for user authentication. Authenticating users is essential to ensuring authorized access and actions in private and secure communications networks. User authentication for software-defined radios and cognitive radios is our focus here. We present various means of authenticating users to their radios and networks, authentication architectures, and the complementary combination of authenticators and architectures. Although devices can be strongly authenticated (e.g., cryptographically), reliably authenticating users is a challenge. To meet this challenge, we capitalize on new forms of user authentication combined with new authentication architectures to support features such as continuous user authentication and varying levels of trust-based authentication. We generalize biometrics to include recognizing user behaviors and use them in concert with knowledge- and token-based authenticators. An integrated approach to user authentication and user authentication architectures is presented here to enhance trusted radio communications networks.
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Summary

Software-defined radios and cognitive radios offer tremendous promise, while having great need for user authentication. Authenticating users is essential to ensuring authorized access and actions in private and secure communications networks. User authentication for software-defined radios and cognitive radios is our focus here. We present various means of authenticating users...

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Biometrically enhanced software-defined radios

System adaptation as a trust response in tactical ad hoc networks

October 13, 2003
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Conference Paper
Author:
Bracha Epstein
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Published in:
IEEE MILCOM 2003, 13-16 October 2003, pp. 209-214.
Topic:
cryptography
R&D area:
R&D group:

Summary

While mobile ad hoc networks offer significant improvements for tactical communications, these networks are vulnerable to node capture and other forms of cyberattack. In this paper we evaluated via simulation of the impact of a passive attacker, a denial of service (DoS) attack, and a data swallowing attack. We compared two different adaptive network responses to these attacks against a baseline of no response for 10 and 20 node networks. Each response reflects a level of trust assigned to the captured node. Our simulation used a responsive variant of the ad hoc on-demand distance vector (AODV) routing algorithm and focused on the response performance. We assumed that the attacks had been detected and reported. We compared performance tradeoffs of attack, response, and network size by focusing on metrics such as "goodput", i.e., percentage of messages that reach the intended destination untainted by the captured node. We showed, for example, that under general conditions a DoS attack response should minimize attacker impact while a response to a data swallowing attack should minimize risk to the system and trust of the compromised node with most of the response benefit. We show that the best network response depends on the mission goals, network configuration, density, network performance, attacker skill, and degree of compromise.
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Summary

While mobile ad hoc networks offer significant improvements for tactical communications, these networks are vulnerable to node capture and other forms of cyberattack. In this paper we evaluated via simulation of the impact of a passive attacker, a denial of service (DoS) attack, and a data swallowing attack. We compared...

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System adaptation as a trust response in tactical ad hoc networks

Speech-to-speech translation: technology and applications study

May 10, 2002
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Technical Report
Author:
Clifford J. Weinstein
Published in:
MIT Lincoln Laboratory Report TR-1080
Topic:
machine translation
R&D area:
R&D group:

Summary

This report describes a study effort on the state-of-the-art and lessons learned in automated, two- way, speech-to-speech translation and its potential application to military problems. The study includes and comments upon an extensive set of references on prior and current work in speech translation. The study includes recommendations on future military applications and on R&D needed to successfully achieve those applications. Key findings of the study include: (1) R&D speech translation systems have been demonstrated, but only in limited domains, and their performance is inadequate for operational use; (2) as far as we have been able to determine, there are currently no operational two-way speech translation systems; (3) intensive, sustained R&D will be needed to develop usable two-way speech translation systems. Major recommendations include: (1) a substantial R&D program in speech translation is needed, especially including full end-to-end system prototyping and evaluation; (2) close cooperation among researchers and users speaking multiple languages will be needed for the development of useful application systems; (3) to get military users involved and interacting in a mode which enables them to provide useful inputs and feedback on system requirements and performance, it will be necessary to provide them at the start with a fairly robust, open-domain system which works to the degree that some two-way speech translation is operational.
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Summary

This report describes a study effort on the state-of-the-art and lessons learned in automated, two- way, speech-to-speech translation and its potential application to military problems. The study includes and comments upon an extensive set of references on prior and current work in speech translation. The study includes recommendations on future...

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Speech-to-speech translation: technology and applications study

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

January 1, 2002
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Journal Article
Author:
Young-Suk Lee
…
Published in:
Machine Trans. Vol. 17, No. 3, 2002, pp. 213-243.
Topic:
machine translation
R&D area:
R&D group:

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.
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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...

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

Toward an improved concept-based information retrieval system

September 9, 2001
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Conference Paper
Author:
Peter V. Henstock
…
Published in:
Proc. of the 24th Annual ACM SIGIR Conf. on Research and Development in Information Retrieval, 9-13 September 2001, pp. 384-385.
Topic:
machine translation
R&D area:
R&D group:

Summary

This paper presents a novel information retrieval system that includes 1) the addition of concepts to facilitate the identification of the correct word sense, 2) a natural language query interface, 3) the inclusion of weights and penalties for proper nouns that build upon the Okapi weighting scheme, and 4) a term clustering technique that exploits the spatial proximity of search terms in a document to further improve the performance. The effectiveness of the system is validated by experimental results.
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Summary

This paper presents a novel information retrieval system that includes 1) the addition of concepts to facilitate the identification of the correct word sense, 2) a natural language query interface, 3) the inclusion of weights and penalties for proper nouns that build upon the Okapi weighting scheme, and 4) a...

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Toward an improved concept-based information retrieval system

Interlingua-based broad-coverage Korean-to-English translation in CCLINC

March 18, 2001
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Conference Paper
Author:
Young-Suk Lee
…
Published in:
Proc. First Int. Conf. on Human Language Technology, 18-21 March 2001.
Topic:
machine translation
R&D area:
R&D group:

Summary

At MIT Lincoln Laboratory, we have been developing a Korean-to-English machine translation system CCLINC (Common Coalition Language System at Lincoln Laboratory). The CCLINC Korean-to-English translation system consists of two core modules, language understanding and generation modules mediated by a language neutral meaning representation called a semantic frame. The key features of the system include: (i) Robust efficient parsing of Korean (a verb final language with overt case markers, relatively free word order, and frequent omissions of arguments). (ii) High quality translation via word sense disambiguation and accurate word order generation of the target language. (iii) Rapid system development and porting to new domains via knowledge-based automated acquisition of grammars. Having been trained on Korean newspaper articles on "missiles" and "chemical biological warfare," the system produces the translation output sufficient for content understanding of the original document.
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Summary

At MIT Lincoln Laboratory, we have been developing a Korean-to-English machine translation system CCLINC (Common Coalition Language System at Lincoln Laboratory). The CCLINC Korean-to-English translation system consists of two core modules, language understanding and generation modules mediated by a language neutral meaning representation called a semantic frame. The key features...

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Interlingua-based broad-coverage Korean-to-English translation in CCLINC
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