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Informative dialect recognition using context-dependent pronunciation modeling

Published in:
Proc. IEEE Int. Conf. on Acoustics, Speech, and Signal Processing, ICASSP, 22-27 May 2011, pp. 4396-4399.

Summary

We propose an informative dialect recognition system that learns phonetic transformation rules, and uses them to identify dialects. A hidden Markov model is used to align reference phones with dialect specific pronunciations to characterize when and how often substitutions, insertions, and deletions occur. Decision tree clustering is used to find context-dependent phonetic rules. We ran recognition tasks on 4 Arabic dialects. Not only do the proposed systems perform well on their own, but when fused with baselines they improve performance by 21-36% relative. In addition, our proposed decision-tree system beats the baseline monophone system in recovering phonetic rules by 21% relative. Pronunciation rules learned by our proposed system quantify the occurrence frequency of known rules, and suggest rule candidates for further linguistic studies.
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Summary

We propose an informative dialect recognition system that learns phonetic transformation rules, and uses them to identify dialects. A hidden Markov model is used to align reference phones with dialect specific pronunciations to characterize when and how often substitutions, insertions, and deletions occur. Decision tree clustering is used to find...

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Assessing the speaker recognition performance of naive listeners using Mechanical Turk

Published in:
Proc. IEEE Int. Conf. on Acoustics, Speech, and Signal Processing, ICASSP, 22-27 May 2011, pp. 5916-5919.

Summary

In this paper we attempt to quantify the ability of naive listeners to perform speaker recognition in the context of the NIST evaluation task. We describe our protocol: a series of listening experiments using large numbers of naive listeners (432) on Amazon's Mechanical Turk that attempts to measure the ability of the average human listener to perform speaker recognition. Our goal was to compare the performance of the average human listener to both forensic experts and state-of-the- art automatic systems. We show that naive listeners vary substantially in their performance, but that an aggregation of listener responses can achieve performance similar to that of expert forensic examiners.
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Summary

In this paper we attempt to quantify the ability of naive listeners to perform speaker recognition in the context of the NIST evaluation task. We describe our protocol: a series of listening experiments using large numbers of naive listeners (432) on Amazon's Mechanical Turk that attempts to measure the ability...

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A time-warping framework for speech turbulence-noise component estimation during aperiodic phonation

Published in:
Proc. IEEE Int. Conf. on Acoustics, Speech, and Signal Processing, ICASSP, 22-27 May 2011, pp. 5404-5407.

Summary

The accurate estimation of turbulence noise affects many areas of speech processing including separate modification of the noise component, analysis of degree of speech aspiration for treating pathological voice, the automatic labeling of speech voicing, as well as speaker characterization and recognition. Previous work in the literature has provided methods by which such a high-quality noise component may be estimated in near-periodic speech, but it is known that these methods tend to leak aperiodic phonation (with even slight deviations from periodicity) into the noise-component estimate. In this paper, we improve upon existing algorithms in conditions of aperiodicity by introducing a time-warping based approach to speech noise-component estimation, demonstrating the results on both natural and synthetic speech examples.
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Summary

The accurate estimation of turbulence noise affects many areas of speech processing including separate modification of the noise component, analysis of degree of speech aspiration for treating pathological voice, the automatic labeling of speech voicing, as well as speaker characterization and recognition. Previous work in the literature has provided methods...

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FDSOI process technology for subthreshold-operation ultra-low power electronics

Published in:
ECS Meeting, 1 May 2011 (in: Adv. Semiconductor-on-Insulator Technol. Rel. Phys., Vol. 35, No. 5, 2011, pp. 179-188).
Topic:

Summary

Ultralow-power electronics will expand the technological capability of handheld and wireless devices by dramatically improving battery life and portability. In addition to innovative low-power design techniques, a complementary process technology is required to enable the highest performance devices possible while maintaining extremely low power consumption. Transistors optimized for subthreshold operation at 0.3 V may achieve a 97% reduction in switching energy compared to conventional transistors. The process technology described in this article takes advantage of the capacitance and performance benefits of thin-body silicon-on-insulator devices, combined with a workfunction engineered mid-gap metal gate.
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Summary

Ultralow-power electronics will expand the technological capability of handheld and wireless devices by dramatically improving battery life and portability. In addition to innovative low-power design techniques, a complementary process technology is required to enable the highest performance devices possible while maintaining extremely low power consumption. Transistors optimized for subthreshold operation...

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Achieving cyber survivability in a contested environment using a cyber moving target

Published in:
High Frontier, Vol. 7, No. 3, May 2011, pp. 9-13.

Summary

We describe two components for achieving cyber survivability in a contested environment: an architectural component that provides heterogeneous computing platforms and an assessment technology that complements the architectural component by analyzing the threat space and triggering reorientation based on the evolving threat level. Together, these technologies provide a cyber moving target that dynamically changes the properties of the system to disadvantage the adversary and provide resiliency and survivability.
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Summary

We describe two components for achieving cyber survivability in a contested environment: an architectural component that provides heterogeneous computing platforms and an assessment technology that complements the architectural component by analyzing the threat space and triggering reorientation based on the evolving threat level. Together, these technologies provide a cyber moving...

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Thermally tuned dual 20-channel ring resonator filter bank in SOI (silicon-on-insulator)

Published in:
CLEO 2011, Conf. on Lasers and Electro-Optics, 1 May 2011.

Summary

Two 20-channel second-order optical filter banks have been fabricated. With tuning, the requirements for a wavelength multiplexed photonic AD-converter (insertion loss 1-3 dB, extinction >30 dB and optical bandwidth 22-27 GHz) are met.
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Summary

Two 20-channel second-order optical filter banks have been fabricated. With tuning, the requirements for a wavelength multiplexed photonic AD-converter (insertion loss 1-3 dB, extinction >30 dB and optical bandwidth 22-27 GHz) are met.

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Distributed multi-modal sensor system for searching a foliage-covered region

Summary

We designed and constructed a system that includes aircraft, ground vehicles, and throwable sensors to search a semiforested region that was partially covered by foliage. The system contained 4 radio-controlled (RC) trucks, 2 aircraft, and 30 SensorMotes (throwable sensors). We also investigated communications links, search strategies, and system architecture. Our system is designed to be low-cost, contain a variety of sensors, and distributed so that the system is robust even if individual components are lost.
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Summary

We designed and constructed a system that includes aircraft, ground vehicles, and throwable sensors to search a semiforested region that was partially covered by foliage. The system contained 4 radio-controlled (RC) trucks, 2 aircraft, and 30 SensorMotes (throwable sensors). We also investigated communications links, search strategies, and system architecture. Our...

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MBE back-illuminated silicon Geiger-mode avalanche photodiodes for enhanced ultraviolet response

Published in:
SPIE Vol. 8033, Advanced Photon Counting Techniques V, 25 April 2011, 80330D.

Summary

We have demonstrated a wafer-scale back-illumination process for silicon Geiger-mode avalanche photodiode arrays using Molecular Beam Epitaxy (MBE) for backside passivation. Critical to this fabrication process is support of the thin (< 10 um) detector during the MBE growth by oxide-bonding to a full-thickness silicon wafer. This back-illumination process makes it possible to build low-dark-count-rate single-photon detectors with high quantum efficiency extending to deep ultraviolet wavelengths. This paper reviews our process for fabricating MBE back-illuminated silicon Geigermode avalanche photodiode arrays and presents characterization of initial test devices.
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Summary

We have demonstrated a wafer-scale back-illumination process for silicon Geiger-mode avalanche photodiode arrays using Molecular Beam Epitaxy (MBE) for backside passivation. Critical to this fabrication process is support of the thin ( 10 um) detector during the MBE growth by oxide-bonding to a full-thickness silicon wafer. This back-illumination process makes...

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Overlapped digital subarray architecture for multiple beam phased array radar

Author:
Published in:
EuCAP 2011, 5th European Conf. on Antrennas and Propagation, 11-15 April 2011, pp. 3027-3030.

Summary

MIT Lincoln Laboratory is conducting a technology demonstration of affordable Multifunction Phased Array Radar (MPAR) technology for Next Generation air traffic control and national weather surveillance services. Aggressive cost and performance goals have been established for the system. The array architecture and its realization using custom Transmit and Receive Integrated Circuits and panel-based Line Replaceable Unit (LRU) will be presented. A program plan for risk reduction and system demonstration will be outlined.
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Summary

MIT Lincoln Laboratory is conducting a technology demonstration of affordable Multifunction Phased Array Radar (MPAR) technology for Next Generation air traffic control and national weather surveillance services. Aggressive cost and performance goals have been established for the system. The array architecture and its realization using custom Transmit and Receive Integrated...

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Uniformity study of wafer-scale InP-to-silicon hybrid integration

Published in:
Appl. Phys. A, Mat. Sci. & Process., Vol. 103, No. 1, April 2011, pp. 213-218.

Summary

In this paper we study the uniformity of up to 150 mm in diameter wafer-scale III-V epitaxial transfer to the Si-on-insulator substrate through the O2 plasma-enhanced low-temperature (300°C) direct wafer bonding. Void-free bonding is demonstrated by the scanning acoustic microscopy with sub-um resolution. The photoluminescence (PL) map shows less than 1 nm change in average peak wavelength, and even improved peak intensity (4% better) and full width at half maximum (41% better) after 150 mm in diameter epitaxial transfer. Small and uniformly distributed residual strain in all sizes of bonding, which is measured by high-resolution X-ray diffraction Omega- 2Theta mapping, and employment of a two-period InP-InGaAsP superlattice at the bonding interface contributes to the improvement of PL response. Preservation of multiple quantum-well integrity is also verified by high-resolution transmission electron microscopy.
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Summary

In this paper we study the uniformity of up to 150 mm in diameter wafer-scale III-V epitaxial transfer to the Si-on-insulator substrate through the O2 plasma-enhanced low-temperature (300°C) direct wafer bonding. Void-free bonding is demonstrated by the scanning acoustic microscopy with sub-um resolution. The photoluminescence (PL) map shows less than...

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