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The MIT-LL/AFRL IWSLT-2006 MT system

Published in:
Proc. Int. Workshop on Spoken Language Translation, IWSLT, 27-28 November 2006.

Summary

The MIT-LL/AFRL MT system is a statistical phrase-based translation system that implements many modern SMT training and decoding techniques. Our system was designed with the long-term goal of dealing with corrupted ASR input and limited amounts of training data for speech-to-speech MT applications. This paper will discuss the architecture of the MIT-LL/AFRL MT system, improvements over our 2005 system, and experiments with manual and ASR transcription data that were run as part of the IWSLT-2006 evaluation campaign.
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Summary

The MIT-LL/AFRL MT system is a statistical phrase-based translation system that implements many modern SMT training and decoding techniques. Our system was designed with the long-term goal of dealing with corrupted ASR input and limited amounts of training data for speech-to-speech MT applications. This paper will discuss the architecture of...

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The JHU Workshop 2006 IWSLT System

Published in:
Int. Workshop on Spoken Language Translation, IWSLT, 27-28 November 2006.

Summary

This paper describes the SMT we built during the 2006 JHU Summer Workshop for the IWSLT 2006 evaluation. Our effort focuses on two parts of the speech translation problem: 1) efficient decoding of word lattices and 2) novel applications of factored translation models to IWSLT-specific problems. In this paper, we present results from the open-track Chinese-to-English condition. Improvements of 5-10% relative BLEU are obtained over a high performing baseline. We introduce a new open-source decoder that implements the state-of-the-art in statistical machine translation.
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Summary

This paper describes the SMT we built during the 2006 JHU Summer Workshop for the IWSLT 2006 evaluation. Our effort focuses on two parts of the speech translation problem: 1) efficient decoding of word lattices and 2) novel applications of factored translation models to IWSLT-specific problems. In this paper, we...

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Low voltage electrowetting using thin fluoroploymer films

Published in:
J. Colloid and Interface Sci., Vol. 303, No. 2, 15 November 2006, pp. 517-524.

Summary

This paper investigates the nonideal electrowetting behavior of thin fluoroploymer films. Results are presented for a three phase system consisting of: (1) an aqueous water droplet containing sodium dodecyl sulfate (SDS), (2) phosphorous-doped silicon topped with SiO2 and an amorphous fluoroploymer (aFP) insulating top layer on which the droplet is situated, and (3) a dodecane oil that surrounds the droplet. The presented measurements indicate that the electrowetting equation is valid down to a 6 nm thick aFP film on a 11 nm thick SiO2. At this dielectric thickness, a remarkable contact angle change of over 100degreescan be achieved with an applied voltage less than 3 V across the system. The data also shows that for this water/surfactant/oil system, contact angle saturation is independent of the electric field, and is reached when the surface energy of the solid-water interface approaches zero.
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Summary

This paper investigates the nonideal electrowetting behavior of thin fluoroploymer films. Results are presented for a three phase system consisting of: (1) an aqueous water droplet containing sodium dodecyl sulfate (SDS), (2) phosphorous-doped silicon topped with SiO2 and an amorphous fluoroploymer (aFP) insulating top layer on which the droplet is...

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ASR-9 refractivity measurements using ground targets

Author:
Published in:
MIT Lincoln Laboratory Report ATC-328

Summary

Weather radars rely on the presence of radiowave scattering entities such as hydrometeors and insects to sense the dynamic evolution of the atmosphere. Under clear-air, low-reflectivity conditions, when no such "visible" tracers are present, air mass boundaries such as the outflow edge of a dry microburst may go undetected. Recently, a radar data processing technique was developed to estimate the near-ground atmospheric refractivity field using ground targets. Refractivity is dependent on the moist thermodynamic variables of the atmosphere and, thus, can be used to detect air mass changes and boundaries. In this study, we apply this technique for the first time to Airport Surveillance Radar-9 (ASR-9) Weather Systems Processor (WSP) data. Comparisons with measurements from a meteorological station show good consistency. The potential exists for improving the capability of the WSP to detect low-reflectivity wind-shear phenomena by adding interest information provided by the estimated refractivity field. Adequate computational power is the sole requirement for implementing this scheme; aside from that, no alteration or addition is necessary to the ASR-9 hardware. Its primary weakness is the sensitivity to vertical variation in refractivity and variance of target height. It also has a limited range of coverage (~20 km), but that is acceptable for terminal-area coverage. Further testing is needed during more appropriate meteorological conditions and at other sites to prove that dry wind-shear events can really be detected in the derived refractivity field by this class of radar, and that the technique is robust under various topographical settings.
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Summary

Weather radars rely on the presence of radiowave scattering entities such as hydrometeors and insects to sense the dynamic evolution of the atmosphere. Under clear-air, low-reflectivity conditions, when no such "visible" tracers are present, air mass boundaries such as the outflow edge of a dry microburst may go undetected. Recently...

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Contribution of photoacid generator to material roughness

Published in:
J. Vac. Sci. Technol. B, Microelectron. Process. Phenon., Vol. 24, No. 6, November/December 2006, pp. 3031-3039 (EIPBN 2006, 30 May-2 June 2006).

Summary

The authors have developed an atomic-force-microscopy-based technique to measure intrinsic material roughness after base development. This method involves performing an interrupted development of the resist film and measuring the resulting film roughness after a certain fixed film loss. Employing this technique, the authors previously established that the photoacid generator (PAG) is a major material contributor of film roughness and that PAG segregation in the resist is likely responsible for nanoscale dissolution inhomogeneities. The additional roughness imparted on a test polymer by incorporation of a series of iodonium, sulfonium, diazo, and imido PAGs was measured. The roughness was then correlated to the inhibition properties of the various PAGs. This was accomplished both through a NMR technique that measures interaction of the PAG with the polymer and by evaluating the dissolution inhibition properties of the PAG through a percolation model. Several PAGs that result in significantly lower material roughness and thus the potential for significantly reduced linewidth roughness in resist imaging have been identified.
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Summary

The authors have developed an atomic-force-microscopy-based technique to measure intrinsic material roughness after base development. This method involves performing an interrupted development of the resist film and measuring the resulting film roughness after a certain fixed film loss. Employing this technique, the authors previously established that the photoacid generator (PAG)...

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Immersion patterning down to 27 nm half pitch

Published in:
J. Vac. Sci. Technol. B, Microelectron. Process. Phenon., Vol. 24, No. 6, November/December 2006, pp. 2789-2797 (EIPBN 2006, 30 May-2 June 2006).

Summary

Liquid immersion interference lithography at 157 nm has been used to print gratings of 27 nm half pitch with a fluorine-doped fused silica prism having index of 1.66. In order to achieve these dimensions, new immersion fluids have been designed and synthesized. These are partially fluorinated organosiloxanes with indexes up to 1.5. Their absorbance is on the order of 0.4/um (base 10), enabling the use of liquid films with micron-size thickness. To utilize these semiabsorptive fluids, an immersion interference printer has been designed, built, and implemented for handling micron-scale liquid layers.
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Summary

Liquid immersion interference lithography at 157 nm has been used to print gratings of 27 nm half pitch with a fluorine-doped fused silica prism having index of 1.66. In order to achieve these dimensions, new immersion fluids have been designed and synthesized. These are partially fluorinated organosiloxanes with indexes up...

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Required surveillance performance accuracy to support 3-mile and 5-mile separation in the National Airspace System

Published in:
MIT Lincoln Laboratory Report ATC-323

Summary

The Federal Aviation Administration is modernizing the Air Traffic Control system to improve flight efficiency, to increase capacity, to reduce flight delays, and to control operating costs as the demand for air travel continues to grow. Promising new surveillance technologies such as Automatic Dependent Surveillance Broadcast, (ADS-B), multisensor track fusion, and multifunction phased array radar offer the potential for increased efficiency in the National Airspace System (NAS). However, the introduction of these surveillance systems into the NAS is hampered because the FAA Order containing the surveillance requirements to support separation services assumes surveillance is provided by radar technology. The requirements are stated in terms that don't apply to new surveillance technologies. In order to take advantage of new surveillance technologies, the surveillance requirements to support separation services in the NAS must be articulated from a performance perspective that is not technology specific. This will allow the FAA to make the investment and performance trade-off analysis necessary to support the introduction of new surveillance technologies. [not complete]
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Summary

The Federal Aviation Administration is modernizing the Air Traffic Control system to improve flight efficiency, to increase capacity, to reduce flight delays, and to control operating costs as the demand for air travel continues to grow. Promising new surveillance technologies such as Automatic Dependent Surveillance Broadcast, (ADS-B), multisensor track fusion...

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High productivity computing and usable petascale systems

Published in:
SC '06: Proceedings of the 2006 ACM/IEEE conference on Supercomputing

Summary

High Performance Computing has seen extraordinary growth in peak performance which has been accompanied by a significant increase in the difficulty of using these systems. High Productivity Computing Systems (HPCS) seek to address this gap by producing petascale computers that are usable by a broader range of scientists and engineers. One of the most important HPCS innovations is the concept of a flatter memory hierarchy, which means that data from remote processors can be retrieved and used very efficiently. A flatter memory hierarchy increases performance and is easier to program.
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Summary

High Performance Computing has seen extraordinary growth in peak performance which has been accompanied by a significant increase in the difficulty of using these systems. High Productivity Computing Systems (HPCS) seek to address this gap by producing petascale computers that are usable by a broader range of scientists and engineers...

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Validating and restoring defense in depth using attack graphs

Summary

Defense in depth is a common strategy that uses layers of firewalls to protect Supervisory Control and Data Acquisition (SCADA) subnets and other critical resources on enterprise networks. A tool named NetSPA is presented that analyzes firewall rules and vulnerabilities to construct attack graphs. These show how inside and outside attackers can progress by successively compromising exposed vulnerable hosts with the goal of reaching critical internal targets. NetSPA generates attack graphs and automatically analyzes them to produce a small set of prioritized recommendations to restore defense in depth. Field trials on networks with up to 3,400 hosts demonstrate that firewalls often do not provide defense in depth due to misconfigurations and critical unpatched vulnerabilities on hosts. In all cases, a small number of recommendations was provided to restore defense in depth. Simulations on networks with up to 50,000 hosts demonstrate that this approach scales well to enterprise-size networks.
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Summary

Defense in depth is a common strategy that uses layers of firewalls to protect Supervisory Control and Data Acquisition (SCADA) subnets and other critical resources on enterprise networks. A tool named NetSPA is presented that analyzes firewall rules and vulnerabilities to construct attack graphs. These show how inside and outside...

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Securing communication of dynamic groups in dynamic network-centric environments

Summary

We developed a new approach and designed a practical solution for securing communication of dynamic groups in dynamic network-centric environments, such as airborne and terrestrial on-the-move networks. The solution is called Public Key Group Encryption (PKGE). In this paper, we define the problem of group encryption, motivate the need for decentralized group encryption services, and explain our vision for designing such services. We then describe our solution, PKGE, at a high-level, and report on the prototype implementation, performance experiments, and a demonstration with GAIM/Jabber chat.
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Summary

We developed a new approach and designed a practical solution for securing communication of dynamic groups in dynamic network-centric environments, such as airborne and terrestrial on-the-move networks. The solution is called Public Key Group Encryption (PKGE). In this paper, we define the problem of group encryption, motivate the need for...

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