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Storage and Database Management for Big Data

Published in:
Big Data: Storage, Sharing, and Security

Summary

The ability to collect and analyze large amounts of data is a growing problem within the scientific community. The growing gap between data and user calls for innovative tools that address the challenges faced by big data volume, velocity, and verity. While there has been great progress in the world of database technologies in the past few years, there are still many fundamental considerations that must be made by scientists. For example, which of the seemingly infinite technologies are the best to use for my problem? Answers to such questions require careful understanding of the technology field in addition to the types of problems that are being solved. This chapter aims to address many of the pressing questions faced by individuals interesting in using sotrage or database technologies to solve their big data problems.
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Summary

The ability to collect and analyze large amounts of data is a growing problem within the scientific community. The growing gap between data and user calls for innovative tools that address the challenges faced by big data volume, velocity, and verity. While there has been great progress in the world...

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Wafer-scale aluminum nanoplasmonic resonators with optimized metal deposition

Summary

Spectroscopic ellipsometry is demonstrated to be an effective technique for assessing the quality of plasmonic resonances within aluminum nanostructures deposited with multiple techniques. The resonance quality of nanoplasmonic aluminum arrays is shown to be strongly dependent on the method of aluminum deposition. Three-layer metal-dielectric-metal nanopillar arrays were fabricated in a complementary metal-oxide semiconductor (CMOS) facility, with the arrays of nanopillars separated from a continuous metal underlayer by a thin dielectric spacer, to provide optimum field enhancement. Nanostructures patterned in optimized aluminum, which had been deposited with a high temperature sputtering process followed by chemical mechanical planarization, display different resonance and depolarization behavior than nanostructures deposited by the more conventional evaporation process. Full plasmonic band diagrams are mapped over a wide range of incidence angles and wavelengths using spectroscopic ellipsometry, and compared for aluminum nanostructures fabricated with two methods. The resonators fabricated from optimized aluminum exhibit a narrower bandwidth of both plasmonic resonance and depolarization parameters, indicating a higher quality resonance due to a stronger localization of the electric field. The optimized wafer-scale aluminum plasmonics fabrication should provide a pathway towards better quality devices for sensing and light detection in the ultraviolet and blue parts of the spectrum.
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Summary

Spectroscopic ellipsometry is demonstrated to be an effective technique for assessing the quality of plasmonic resonances within aluminum nanostructures deposited with multiple techniques. The resonance quality of nanoplasmonic aluminum arrays is shown to be strongly dependent on the method of aluminum deposition. Three-layer metal-dielectric-metal nanopillar arrays were fabricated in a...

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Cryptography for Big Data security

Published in:
Chapter 10 in Big Data: Storage, Sharing, and Security, 2016, pp. 214-87.

Summary

This chapter focuses on state-of-the-art provably secure cryptographic techniques for protecting big data applications. We do not focus on more established, and commonly available cryptographic solutions. The goal is to inform practitioners of new techniques to consider as they develop new big data solutions rather than to summarize the current best practice for securing data.
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Summary

This chapter focuses on state-of-the-art provably secure cryptographic techniques for protecting big data applications. We do not focus on more established, and commonly available cryptographic solutions. The goal is to inform practitioners of new techniques to consider as they develop new big data solutions rather than to summarize the current...

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Named entity recognition in 140 characters or less

Published in:
Proc. of the 6th Workshop on "Making Sense of Microposts" (part of: 25th Int. World Wide Web Conf., 11 April 2016), #Microposts2016, pp. 78-79.

Summary

In this paper, we explore the problem of recognizing named entities in microposts, a genre with notoriously little context surrounding each named entity and inconsistent use of grammar, punctuation, capitalization, and spelling conventions by authors. In spite of the challenges associated with information extraction from microposts, it remains an increasingly important genre. This paper presents the MIT Information Extraction Toolkit (MITIE) and explores its adaptability to the micropost genre.
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Summary

In this paper, we explore the problem of recognizing named entities in microposts, a genre with notoriously little context surrounding each named entity and inconsistent use of grammar, punctuation, capitalization, and spelling conventions by authors. In spite of the challenges associated with information extraction from microposts, it remains an increasingly...

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A reverse approach to named entity extraction and linking in microposts

Published in:
Proc. of the 6th Workshop on "Making Sense of Microposts" (part of: 25th Int. World Wide Web Conf., 11 April 2016), #Microposts2016, pp. 67-69.

Summary

In this paper, we present a pipeline for named entity extraction and linking that is designed specifically for noisy, grammatically inconsistent domains where traditional named entity techniques perform poorly. Our approach leverages a large knowledge base to improve entity recognition, while maintaining the use of traditional NER to identify mentions that are not co-referent with any entities in the knowledge base.
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Summary

In this paper, we present a pipeline for named entity extraction and linking that is designed specifically for noisy, grammatically inconsistent domains where traditional named entity techniques perform poorly. Our approach leverages a large knowledge base to improve entity recognition, while maintaining the use of traditional NER to identify mentions...

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Blind signal classification via sparse coding

Published in:
IEEE Int. Conf. Computer Communications, IEEE INFOCOM 2016, 10-15 April 2016.

Summary

We propose a novel RF signal classification method based on sparse coding, an unsupervised learning method popular in computer vision. In particular, we employ a convolutional sparse coder that can extract high-level features by computing the maximal similarity between an unknown received signal against an overcomplete dictionary of matched filter templates. Such dictionary can be either generated or trained in an unsupervised fashion from signal examples labeled with no ground truths. The computed sparse code then is applied to train SVM classifiers to discriminate RF signals. As a result, the proposed approach can achieve blind signal classification that requires no prior knowledge (e.g., MCS, pulse shaping) about the signals present in an arbitrary RF channel. Since modulated RF signals undergo pulse shaping to aid the matched filter detection by a receiver for the same radio protocol, our method can exploit variability in relative similarity against the dictionary atoms as the key discriminating factor for SVM. We present an empirical validation of our approach. The results indicate that we can separate different classes of digitally modulated signals from blind sampling with 70.3% recall and 24.6% false alarm at 10 dB SNR. If a labeled dataset were available for supervised classifier training, we can enhance the classification accuracy to 87.8% recall and 14.1% false alarm.
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Summary

We propose a novel RF signal classification method based on sparse coding, an unsupervised learning method popular in computer vision. In particular, we employ a convolutional sparse coder that can extract high-level features by computing the maximal similarity between an unknown received signal against an overcomplete dictionary of matched filter...

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Geiger-mode avalanche photodiode arrays integrated to all-digital CMOS circuits

Author:
Published in:
Sensors, Vol. 16, No. 495, 2016, doi:10.3390/s16040495.

Summary

This article reviews MIT Lincoln Laboratory's work over the past 20 years to develop photon-sensitive image sensors based on arrays of silicon Geiger-mode avalanche photodiodes. Integration of these detectors to all-digital CMOS readout circuits enable exquisitely sensitive solid-state imagers for lidar, wavefront sensing, and passive imaging.
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Summary

This article reviews MIT Lincoln Laboratory's work over the past 20 years to develop photon-sensitive image sensors based on arrays of silicon Geiger-mode avalanche photodiodes. Integration of these detectors to all-digital CMOS readout circuits enable exquisitely sensitive solid-state imagers for lidar, wavefront sensing, and passive imaging.

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Boston community energy study - zonal analysis for urban microgrids

Published in:
MIT Lincoln Laboratory Report TR-1201

Summary

Superstorm Sandy illustrated the economic and human impact that severe weather can have on urban areas such as New York City. While flooding and wind damaged or destroyed some of the energy infrastructure, all installed microgrids in the New York City region remained operational during Sandy, including those at Princeton University, Goldman Sachs, New York University, and Co-op City. The resilience provided by these microgrids sparked renewed interest in pursuing more microgrid deployments as means to increase resiliency throughout the nation and in the face of many potential threats including severe weather events, and potentially terrorism. MIT Lincoln Laboratory has been engaged with the Department of Homeland Security (DHS), the Department of Energy (DoE), and the City of Boston in this Community Energy Study to explore the potential for microgrid deployment within Boston's thriving neighborhoods. Using hourly simulated building energy data for every building in Boston, provided by the Sustainable Design Lab on MIT campus, MIT Lincoln Laboratory was able to develop an approach that can identify zones within the city where microgrids could be implemented with a high return on investment in terms of resiliency, offering both cost savings and social benefit in the face of grid outages. An important part of this approach leverages a microgrid optimization tool developed by Lawrence Berkeley National Laboratory, with whom the MIT Lincoln Laboratory is now collaborating on microgrid modeling work. Using the microgrid optimization tool, along with building energy use data, forty-two community microgrids were identified, including ten multiuser microgrids, ten energy justice microgrids, and twenty-two emergency microgrids.
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Summary

Superstorm Sandy illustrated the economic and human impact that severe weather can have on urban areas such as New York City. While flooding and wind damaged or destroyed some of the energy infrastructure, all installed microgrids in the New York City region remained operational during Sandy, including those at Princeton...

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Microhydraulic electrowetting actuators

Published in:
J. Microelectromech. Syst., Vol. 25, No. 2, April 2016, pp. 394-400.

Summary

The conversion of electrical to mechanical power on a sub-centimeter scale is a key technology in many microsystems and energy harvesting devices. In this paper, we present a type of a capacitive energy conversion device that uses capillary pressure and electrowetting to reversibly convert electrical power to hydraulic power. These microhydraulic actuators use a high surface-to-volume ratio to deliver high power at a relatively low voltage with an energy conversion efficiency of over 65%. The capillary pressure generated grows linearly with shrinking capillary diameter, as does the frequency of actuation. We present the pressure, frequency, and power scaling properties of these actuators and demonstrate that power density scales up as the inverse capillary diameter squared, leading to high-efficiency actuators with a strength density exceeding biological muscle. Two potential applications for microhydraulics are also demonstrated: soft-microrobotics and energy harvesting.
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Summary

The conversion of electrical to mechanical power on a sub-centimeter scale is a key technology in many microsystems and energy harvesting devices. In this paper, we present a type of a capacitive energy conversion device that uses capillary pressure and electrowetting to reversibly convert electrical power to hydraulic power. These...

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2015 operational observation of CoSPA and traffic flow impact

Published in:
MIT Lincoln Laboratory Report ATC-429

Summary

This technical report summarizes the operational observations recorded by MIT Lincoln Laboratory (MIT LL) aviation subject matter experts during the period 13 April to 31 October 2015. Three separate field observations were conducted over four convective weather days across the eastern National Airspace System (NAS) with visits to five separate FAA facilities and five different airline operation centers. Observations of strategic management planning and decision making were documented during these visits. Specifically noted were the utilization of the deterministic convective weather forecasting model, CoSPA, and a newly developed decision support application, Traffic Flow Impact (TFI). These field evaluations were supported via the FAA AJM-334 CoSPA program.
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Summary

This technical report summarizes the operational observations recorded by MIT Lincoln Laboratory (MIT LL) aviation subject matter experts during the period 13 April to 31 October 2015. Three separate field observations were conducted over four convective weather days across the eastern National Airspace System (NAS) with visits to five separate...

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