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Guaranteeing spoof-resilient multi-robot networks

July 13, 2015
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Conference Paper
Author:
Stephanie Gil
…
Published in:
2015 Robotics: Science and Systems Conf., 13-17 July 2015.
Topic:
cyber security
R&D area:
R&D group:

Summary

Multi-robot networks use wireless communication to provide wide-ranging services such as aerial surveillance and unmanned delivery. However, effective coordination between multiple robots requires trust, making them particularly vulnerable to cyber-attacks. Specifically, such networks can be gravely disrupted by the Sybil attack, where even a single malicious robot can spoof a large number of fake clients. This paper proposes a new solution to defend against the Sybil attack, without requiring expensive cryptographic key-distribution. Our core contribution is a novel algorithm implemented on commercial Wi-Fi radios that can "sense" spoofers using the physics of wireless signals. We derive theoretical guarantees on how this algorithm bounds the impact of the Sybil Attack on a broad class of robotic coverage problems. We experimentally validate our claims using a team of AscTec quadrotor servers and iRobot Create ground clients, and demonstrate spoofer detection rates over 96%.
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Summary

Multi-robot networks use wireless communication to provide wide-ranging services such as aerial surveillance and unmanned delivery. However, effective coordination between multiple robots requires trust, making them particularly vulnerable to cyber-attacks. Specifically, such networks can be gravely disrupted by the Sybil attack, where even a single malicious robot can spoof a...

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Guaranteeing spoof-resilient multi-robot networks

Temporal and multi-source fusion for detection of innovation in collaboration networks

July 6, 2015
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Conference Paper
Author:
Benjamin A. Miller
…
Published in:
Proc. of the 18th Int. Conf. On Information Fusion, 6-9 July 2015.
Topic:
big data
R&D area:
R&D group:

Summary

A common problem in network analysis is detecting small subgraphs of interest within a large background graph. This includes multi-source fusion scenarios where data from several modalities must be integrated to form the network. This paper presents an application of novel techniques leveraging the signal processing for graphs algorithmic framework, to well-studied collaboration networks in the field of evolutionary biology. Our multi-disciplinary approach allows us to leverage case studies of transformative periods in this scientific field as truth. We build on previous work by optimizing the temporal integration filters with respect to truth data using a tensor decomposition method that maximizes the spectral norm of the integrated subgraph's adjacency matrix. We also demonstrate that we can mitigate data corruption via fusion of different data sources, demonstrating the power of this analysis framework for incomplete and corrupted data.
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Summary

A common problem in network analysis is detecting small subgraphs of interest within a large background graph. This includes multi-source fusion scenarios where data from several modalities must be integrated to form the network. This paper presents an application of novel techniques leveraging the signal processing for graphs algorithmic framework...

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Temporal and multi-source fusion for detection of innovation in collaboration networks

Thermal and residual excited-state population in a 3D transmon qubit

June 19, 2015
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Journal Article
Author:
X. Y. Jin
…
Published in:
Phys. Rev. Lett., Vol. 114, No. 24, 19 June 2015, 240501.
Topic:
computing
R&D area:
R&D group:

Summary

Remarkable advancements in coherence and control fidelity have been achieved in recent years with cryogenic solid-state qubits. Nonetheless, thermalizing such devices to their milliKelvin environments has remained a long-standing fundamental and technical challenge. In this context, we present a systematic study of the first-excited-state population in a 3D transmon superconducting qubit mounted in a dilution refrigerator with a variable temperature. Using a modified version of the protocol developed by Geerlings et al., we observe the excited-state population to be consistent with a Maxwell-Boltzmann distribution, i.e., a qubit in thermal equilibrium with the refrigerator, over the temperature range 35-150 mK. Below 35 mK, the excited-state population saturates at approximately 0.1%. We verified this result using a flux qubit with ten times stronger coupling to its readout resonator. We conclude that these qubits have effective temperature Teff ơ 35 mK. Assuming Teff is due solely to hot quasiparticles, the inferred qubit lifetime is 108 microns and in plausible agreement with the measured 80 microns.
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Summary

Remarkable advancements in coherence and control fidelity have been achieved in recent years with cryogenic solid-state qubits. Nonetheless, thermalizing such devices to their milliKelvin environments has remained a long-standing fundamental and technical challenge. In this context, we present a systematic study of the first-excited-state population in a 3D transmon superconducting...

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Thermal and residual excited-state population in a 3D transmon qubit

Aircraft in situ validation of hydrometeors and icing conditions inferred by ground-based NEXRAD polarimetric radar

June 15, 2015
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Conference Paper
Author:
Earle R. Williams
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Published in:
SAE Int. Conf. on Icing of Aircraft, Engines, and Structures, ICE 2015, 15 June 2015.
Topic:
aviation weather
R&D area:
R&D group:

Summary

MIT Lincoln Laboratory is tasked by the U.S. Federal Aviation Administration to investigate the use of the NEXRAD polarimetric radars for the remote sensing of icing conditions hazardous to aircraft. A critical aspect of the investigation concerns validation that has relied upon commercial airline icing pilot reports and a dedicated campaign of in situ flights in winter storms. During the month of February in 2012 and 2013, the Convair-580 aircraft operated by the National Research Council of Canada was used for in situ validation of snowstorm characteristics under simultaneous observation by NEXRAD radars in Cleveland, Ohio and Buffalo, New York. The most anisotropic and easily distinguished winter targets to dual pol radar are ice crystals. Accordingly, laboratory diffusion chamber measurements in a tightly-controlled parameter space of temperature and humidity provide the linkage between shape and the expectation for the presence/absence of water saturation conditions necessary for icing hazard in situ. In agreement with the laboratory measurements pertaining to dendritic and hexagonal flat plate crystals, the aircraft measurements have verified the presence of supercooled water in mainly low concentrations coincident with regions showing layered anomalies of positive differential reflectivity (ZDR) by ground-based radar, otherwise known as +ZDR 'bright bands'. Extreme values of ZDR (up to +8 dB) have also been found to be coincident with hexagonal flat plate crystals and intermittent supercooled water, also consistent with laboratory measurements. The icing conditions found with the anisotropic description are considered non-classical (condensation/collision-coalescence) and require the ascent of air and availability of ice nuclei. A modest ascent rate (
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Summary

MIT Lincoln Laboratory is tasked by the U.S. Federal Aviation Administration to investigate the use of the NEXRAD polarimetric radars for the remote sensing of icing conditions hazardous to aircraft. A critical aspect of the investigation concerns validation that has relied upon commercial airline icing pilot reports and a dedicated...

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Aircraft in situ validation of hydrometeors and icing conditions inferred by ground-based NEXRAD polarimetric radar

Analyzing Mission Impacts of Cyber Actions (AMICA)

June 15, 2015
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Conference Paper
Author:
Steven Noel
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Published in:
Proc. NATO S&T Workshop on Cyber Attack, Detection, Forensics and Attribution for Assessment of Mission Impact, 15 June 2015.
Topic:
machine learning
R&D area:
R&D group:

Summary

This paper describes AMICA (Analyzing Mission Impacts of Cyber Actions), an integrated approach for understanding mission impacts of cyber attacks. AMICA combines process modeling, discrete-event simulation, graph-based dependency modeling, and dynamic visualizations. This is a novel convergence of two lines of research: process modeling/simulation and attack graphs. AMICA captures process flows for mission tasks as well as cyber attacker and defender tactics, techniques, and procedures (TTPs). Vulnerability dependency graphs map network attack paths, and mission-dependency graphs define the hierarchy of high-to-low-level mission requirements mapped to cyber assets. Through simulation of the resulting integrated model, we quantify impacts in terms of mission-based measures, for various mission and threat scenarios. Dynamic visualization of simulation runs provides deeper understanding of cyber warfare dynamics, for situational awareness in the context of simulated conflicts. We demonstrate our approach through a prototype tool that combines operational and systems views for rapid analysis.
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Summary

This paper describes AMICA (Analyzing Mission Impacts of Cyber Actions), an integrated approach for understanding mission impacts of cyber attacks. AMICA combines process modeling, discrete-event simulation, graph-based dependency modeling, and dynamic visualizations. This is a novel convergence of two lines of research: process modeling/simulation and attack graphs. AMICA captures process...

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Analyzing Mission Impacts of Cyber Actions (AMICA)

Sensitive detection and identification of isovanillin aerosol particles at the pg/cm^3 mass concentration level using Raman spectroscopy

June 8, 2015
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Journal Article
Author:
Roshan L. Aggarwal
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Published in:
Aerosol Sci. Technol., Vol. 49, No. 9, 2015, pp. 753-6.
Topic:
detection systems
R&D area:
R&D group:

Summary

A compact Raman spectroscopy system with high sensitivity to chemical aerosols has been developed. This system has been used to detect isovanillin aerosols with mass concentration of 12 pg/cm3 in a 15 s signal integration period with a signal-to-noise ratio of 32. We believe this represents the lowest chemical aerosol concentration and signal integration period product ever reported for a Raman spectroscopy system. The Raman system includes (i) a 10 W, 532-nm cw laser, (ii) an aerosol flow cell, (iii) a 60x aerosol concentrator, (iv) an f/1.8 Raman spectrometer with a spectral range of 400-1400 cm^-1 and a resolution of 4 cm^-1, and (v) a low-noise CCD camera (1340 x 400 pixels). The collection efficiency of the Raman system has been determined to be 2.8%. Except for the laser cooling subsystem, the Raman system fits in a 0.61 m x 0.61 m x 0.61 m box.
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Summary

A compact Raman spectroscopy system with high sensitivity to chemical aerosols has been developed. This system has been used to detect isovanillin aerosols with mass concentration of 12 pg/cm3 in a 15 s signal integration period with a signal-to-noise ratio of 32. We believe this represents the lowest chemical aerosol...

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Sensitive detection and identification of isovanillin aerosol particles at the pg/cm^3 mass concentration level using Raman spectroscopy

Snapshot on-chip HDR ROIC architectures

June 7, 2015
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Conference Paper
Author:
Christy F. Cull
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Published in:
Computational Optical Sensing and Imaging, 7-11 June 2015.
Topic:
optics
R&D area:
R&D group:

Summary

We describe novel digital readout integrated circuits (DROICs) that achieve snapshot on-chip high dynamic range imaging where most commercial systems require a multiple exposure acquisition.
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Summary

We describe novel digital readout integrated circuits (DROICs) that achieve snapshot on-chip high dynamic range imaging where most commercial systems require a multiple exposure acquisition.

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Snapshot on-chip HDR ROIC architectures

In situ microfluidic SERS assay for monitoring enzymatic breakdown of organophosphates

June 3, 2015
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Journal Article
Author:
Vladimir Liberman
…
Published in:
Nanoscale, Vol. 7, No. 25, 2015, 11013-23.
Topic:
nanotechnologies
R&D area:
R&D group:

Summary

In this paper, we report on a method to probe the breakdown of the organophosphate (OP) simulants o, s-diethyl methyl phosphonothioate (OSDMP) and demeton S by the enzyme organophosphorous hydrolase (OPH) in a microfluidic device by surface enhanced Raman spectroscopy (SERS). SERS hotspots were formed on-demand inside the microfluidic device by laser-induced aggregation of injected Ag NPs suspensions. The Ag NP clusters, covering micron-sized areas, were formed within minutes using a conventional confocal Raman laser microscope. These Ag NP clusters were used to enhance the Raman spectra of the thiol products of OP breakdown in the microfluidic device: ethanethiol (EtSH) and (ethylsulfanyl) ethane-1-thiol (2-EET). When the OPH enzyme and its substrates OSDMP and demeton S were introduced, the thiolated breakdown products were generated, resulting in changes in the SERS spectra. With the ability to analyze reaction volumes as low as 20 nL, our approach demonstrates great potential for miniaturization of SERS analytical protocols.
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Summary

In this paper, we report on a method to probe the breakdown of the organophosphate (OP) simulants o, s-diethyl methyl phosphonothioate (OSDMP) and demeton S by the enzyme organophosphorous hydrolase (OPH) in a microfluidic device by surface enhanced Raman spectroscopy (SERS). SERS hotspots were formed on-demand inside the microfluidic device...

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In situ microfluidic SERS assay for monitoring enzymatic breakdown of organophosphates

Inductance of circuit structures for MIT LL superconductor electronics fabrication process with 8 niobium layers

June 1, 2015
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Journal Article
Author:
Sergey K. Tolpygo
…
Published in:
IEEE Trans. Appl. Supercond., Vol. 25, No. 3, 1 June 2015, 1100905.
Topic:
integrated circuit
R&D area:
R&D group:

Summary

Inductance of superconducting thin-film inductors and structures with linewidth down to 250 nm has been experimentally evaluated. The inductors include various striplines and microstrips, their 90 degree bends and meanders, interlayer vias, etc., typically used in superconducting digital circuits. The circuits have been fabricated by a fully planarized process with 8 niobium layers, developed at MIT Lincoln Laboratory for very-large-scale superconducting integrated circuits. Excellent run-to-run reproducibility and inductance uniformity of better than 1% across 200-mm wafers have been found. It has been found that the inductance per unit length of stripline and microstrip line inductors continues to grow as the inductor linewidth is reduced deep into the submicron range to the widths comparable to the film thickness and magnetic field penetration depth. It is shown that the linewidth reduction does not lead to widening of the parameter spread due to diminishing sensitivity of the inductance to the linewidth and dielectric thickness. The experimental results were compared with numeric inductance extraction using commercial software and freeware, and a good agreement was found for 3-D inductance extractors. Methods of further miniaturization of circuit inductors for achieving circuit densities >10^6 Josephson junctions per cm^2 are discussed.
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Summary

Inductance of superconducting thin-film inductors and structures with linewidth down to 250 nm has been experimentally evaluated. The inductors include various striplines and microstrips, their 90 degree bends and meanders, interlayer vias, etc., typically used in superconducting digital circuits. The circuits have been fabricated by a fully planarized process with...

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Inductance of circuit structures for MIT LL superconductor electronics fabrication process with 8 niobium layers

Fabrication process and properties of fully planarized deep-submicron Nb/Al-AlOx/Nb Josephson junctions for VLSI circuits

June 1, 2015
  |
Journal Article
Author:
Sergey K. Tolpygo
…
Published in:
IEEE Trans. Appl. Supercond., Vol. 25, No. 3, June 2015, 1101312.
Topic:
integrated circuit
R&D area:
R&D group:

Summary

A fabrication process for Nb/Al-AlOx/Nb Josephson junctions (JJs) with sizes down to 200 nm has been developed on a 200-mm-wafer tool set typical for CMOS foundry. This process is the core of several nodes of a roadmap for fully-planarized fabrication processes for superconductor integrated circuits with 4, 8, and 10 niobium layers developed at MIT Lincoln Laboratory. The process utilizes 248 nm photolithography, anodization, high-density plasma etching, and chemical mechanical polishing (CMP) for planarization of SiO2 interlayer dielectric. JJ electric properties and statistics such as on-chip and wafer spreads of critical current, Ic, normal-state conductance, GN, and run-to-run reproducibility have been measured on 200-mm wafers over a broad range of JJ diameters from 200 nm to 1500 nm and critical current densities, Jc, from 10 kA/cm^2 to 50 kA/cm^2 where the JJs become self-shunted. Diffraction-limited photolithography of JJs is discussed. A relationship between JJ mask size, JJ size on wafer, and the minimum printable size for coherent and partially coherent illumination has been worked out. The GN and Ic spreads obtained have been found to be mainly caused by variations of the JJ areas and agree with the model accounting for an enhancement of mask errors near the diffraction-limited minimum printable size of JJs. Ic and GN spreads from 0.8% to 3% have been obtained for JJs with sizes form 1500 nm down to 500 nm. The spreads increase to about 8% for 200-nm JJs. Prospects for circuit densities > 10^6 JJ/cm^2 and 193-nm photolithography for JJ definition are discussed.
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Summary

A fabrication process for Nb/Al-AlOx/Nb Josephson junctions (JJs) with sizes down to 200 nm has been developed on a 200-mm-wafer tool set typical for CMOS foundry. This process is the core of several nodes of a roadmap for fully-planarized fabrication processes for superconductor integrated circuits with 4, 8, and 10...

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Fabrication process and properties of fully planarized deep-submicron Nb/Al-AlOx/Nb Josephson junctions for VLSI circuits
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