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Geospatial analysis based on GIS integrated with LADAR

October 7, 2013
  |
Journal Article
Author:
Matthew R Fetterman
…
Published in:
Opt. Express, Vol. 21, No. 20, 7 October 2013, pp. 23579-91.
Topic:
ladar
R&D area:
R&D group:

Summary

In this work, we describe multi-layered analyses of a high-resolution broad-area LADAR data set in support of expeditionary activities. High-level features are extracted from the LADAR data, such as the presence and location of buildings and cars, and then these features are used to populate a GIS (geographic information system) tool. We also apply line-of-sight (LOS) analysis to develop a path-planning module. Finally, visualization is addressed and enhanced with a gesture-based control system that allows the user to navigate through the enhanced data set in a virtual immersive experience. This work has operational applications including military, security, disaster relief, and task-based robotic path planning.
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Summary

In this work, we describe multi-layered analyses of a high-resolution broad-area LADAR data set in support of expeditionary activities. High-level features are extracted from the LADAR data, such as the presence and location of buildings and cars, and then these features are used to populate a GIS (geographic information system)...

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Geospatial analysis based on GIS integrated with LADAR

Materials in superconducting quantum bits

October 1, 2013
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Journal Article
Author:
William D. Oliver
…
Published in:
MRS Bulletin, Vol 38, October 2013, pp. 816-825.
Topic:
advanced materials
R&D area:
R&D group:

Summary

Superconducting qubits are electronic circuits comprising lithographically defined Josephson tunnel junctions, inductors, capacitors, and interconnects. When cooled to dillution refrigerator temperatures, these circuits behave as quantum mechanical "artificial atoms," exhibiting quantized states of electronic charge, magnetic flux, or junction phase depending on the design parameters of the constituent circuit elements. Their potential for lithographic scalability, compatibility with microwave control, and operability at nanosecond time scales place superconducting qubits among the leading modalities being considered for quantum information science and technology applications. Over the past decade, the quantum coherence of superconducting qubits has increased more than five orders of magnitude, due primarily to improvements in their design, fabrication, and, importantly, their constituent materials and interfaces. In this article, we review superconducting qubits, articulate the important role of materials research in their development, and provide a prospectus for the future as these devices transition from scientific curiosity to the threshold of technical reality.
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Summary

Superconducting qubits are electronic circuits comprising lithographically defined Josephson tunnel junctions, inductors, capacitors, and interconnects. When cooled to dillution refrigerator temperatures, these circuits behave as quantum mechanical "artificial atoms," exhibiting quantized states of electronic charge, magnetic flux, or junction phase depending on the design parameters of the constituent circuit elements...

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Materials in superconducting quantum bits

Exploring the variable sky with LINEAR. III. classification of periodic light curves

October 1, 2013
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Journal Article
Author:
Lovro Palaversa
…
Published in:
Astron. J., Vol. 146, No. 101, October 2013.
Topic:
LINEAR
R&D area:
R&D group:

Summary

We describe the construction of a highly reliable sample of ~7000 optically faint periodic variable stars with light curves obtained by the asteroid survey LINEAR across 10,000 deg^2 of the northern sky. The majority of these variables have not been cataloged yet. The sample flux limit is several magnitudes fainter than most other wide-angle surveys; the photometric errors range from ~0.03 mag at r = 15 to ~0.20 mag at r = 18. Light curves include on average 250 data points, collected over about 25 million objects, we selected ~200,000 most probable candidate variables with r
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Summary

We describe the construction of a highly reliable sample of ~7000 optically faint periodic variable stars with light curves obtained by the asteroid survey LINEAR across 10,000 deg^2 of the northern sky. The majority of these variables have not been cataloged yet. The sample flux limit is several magnitudes fainter...

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Exploring the variable sky with LINEAR. III. classification of periodic light curves

Gigahertz (GHz) hard X-ray imaging using fast scintillators

September 26, 2013
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Conference Paper
Author:
Zhehui Wang
…
Published in:
SPIE Vol. 8852, Hard X-Ray, Gamma-Ray, and Neutron Detector Physics XV, 26 September 2013, 88521A.
Topic:
optics
R&D area:
R&D group:

Summary

Gigahertz (GHz) imaging technology will be needed at high-luminosity X-ray and charged particle sources. It is plausible to combine fast scintillators with the latest picosecond detectors and GHz electronics for multi-frame hard X-ray imaging and achieve an inter-frame time of elss than 10 ns. The time responses and light yield of LYSO, LaBr3, BaF2 and ZnO are measured using an MCP-PMT detector. Zinc Oxide (ZnO) is an attractive material for fast hard X-ray imaging based on GEANT4 simulations and previous studies, but the measured light yield from the samples is much lower than expected.
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Summary

Gigahertz (GHz) imaging technology will be needed at high-luminosity X-ray and charged particle sources. It is plausible to combine fast scintillators with the latest picosecond detectors and GHz electronics for multi-frame hard X-ray imaging and achieve an inter-frame time of elss than 10 ns. The time responses and light yield...

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Gigahertz (GHz) hard X-ray imaging using fast scintillators

Wind-shear detection performance analysis for MPAR risk reduction

September 16, 2013
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Conference Paper
Author:
John Y. Cho
…
Published in:
36th Conf. on Radar Meteorology, 16 September 2013.
Topic:
detection systems
R&D area:
R&D group:

Summary

Multifunction phased array radars (MPARs) of the future that may replace the current terminal wind-shear detection systems will need to meet the Federal Aviation Administration's (FAA) detection requirements. Detection performance issues related to on-airport siting of MPAR, its broader antenna beamwidth relative to the Terminal Doppler Weather Radar (TDWR), and the change in operational frequency from C band to S band are analyzed. Results from the 2012 MPAR Wind-Shear Experiment are presented, with microburst and gust-front detection statistics for the Oklahoma City TDWR and the National Weather Radar Testbed (NWRT) phased array radar, which are located 6 km apart. The NWRT has sensitivity and beamwidth similar to a conceptual terminal MPAR (TMPAR), which is a scaled-down version of a full-size MPAR. The micro-burst results show both the TDWR probability of detec-tion (POD) and the estimated NWRT POD exceeding the 90% requirement. For gust fronts, however, the overall estimated NWRT POD was more than 10% lower than the TDWR POD. NWRT data are also used to demonstrate that rapid-scan phased array radar has the potential to enhance microburst prediction capability.
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Summary

Multifunction phased array radars (MPARs) of the future that may replace the current terminal wind-shear detection systems will need to meet the Federal Aviation Administration's (FAA) detection requirements. Detection performance issues related to on-airport siting of MPAR, its broader antenna beamwidth relative to the Terminal Doppler Weather Radar (TDWR), and...

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Wind-shear detection performance analysis for MPAR risk reduction

Validation of NEXRAD radar differential reflectivity in snowstorms with airborne microphysical measurements: evidence for hexagonal flat plate crystals

September 16, 2013
  |
Conference Paper
Author:
Earle R. Williams
…
Published in:
36th Conf. on Radar Meteorology, 16 September 2013.
Topic:
aviation weather
R&D area:
R&D group:

Summary

This study is concerned with the use of cloud microphysical aircraft measurements (the Convair 580) to verify the origin of differential reflectivity (ZDR) measured with a ground-based radar (the WSR-88D KBUF radar in Buffalo, New York). The underlying goal is to make use of the radar measurements to infer the presence or absence of supercooled water, which may pose an icing hazard to aircraft. The context of these measurements is the investment by the Federal Aviation Administration in the use of NEXRAD polarimetric radar and is addressed in the companion paper by Smalley et al. (2013, this Conference). The highlight of the measurements on February 28, 2013 was the finding of sustained populations of hexagonal flat plate crystals over a large area northwest of the KBUF radar, in conditions of dilute and intermittent supercooled water concentration. Some background discussion is in order prior to the discussion of the aircraft/radar observations that form the main body of this study. The anisotropy of hydrometeors, the role of humidity and temperature in crystal shape, and the common presence of hexagonal flat plate crystals in the laboratory cold box experiment are all discussed in turn.
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Summary

This study is concerned with the use of cloud microphysical aircraft measurements (the Convair 580) to verify the origin of differential reflectivity (ZDR) measured with a ground-based radar (the WSR-88D KBUF radar in Buffalo, New York). The underlying goal is to make use of the radar measurements to infer the...

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Validation of NEXRAD radar differential reflectivity in snowstorms with airborne microphysical measurements: evidence for hexagonal flat plate crystals

D4M 2.0 Schema: a general purpose high performance schema for the Accumulo database

September 10, 2013
  |
Conference Paper
Author:
Jeremy Kepner
…
Published in:
HPEC 2013: IEEE Conf. on High Performance Extreme Computing, 10-12 September 2013.
Topic:
supercomputing
R&D area:
R&D group:

Summary

Non-traditional, relaxed consistency, triple store databases are the backbone of many web companies (e.g., Google Big Table, Amazon Dynamo, and Facebook Cassandra). The Apache Accumulo database is a high performance open source relaxed consistency database that is widely used for government applications. Obtaining the full benefits of Accumulo requires using novel schemas. The Dynamic Distributed Dimensional Data Model (D4M) [http://www.mit.edu/~kepner/D4M] provides a uniform mathematical framework based on associative arrays that encompasses both traditional (i.e., SQL) and non-traditional databases. For non-traditional databases D4M naturally leads to a general purpose schema that can be used to fully index and rapidly query every unique string in a dataset. The D4M 2.0 Schema has been applied with little or no customization to cyber, bioinformatics, scientific citation, free text, and social media data. The D4M 2.0 Schema is simple, requires minimal parsing, and achieves the highest published Accumulo ingest rates. The benefits of the D4M 2.0 Schema are independent of the D4M interface. Any interface to Accumulo can achieve these benefits by using the D4M 2.0 Schema.
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Summary

Non-traditional, relaxed consistency, triple store databases are the backbone of many web companies (e.g., Google Big Table, Amazon Dynamo, and Facebook Cassandra). The Apache Accumulo database is a high performance open source relaxed consistency database that is widely used for government applications. Obtaining the full benefits of Accumulo requires using...

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D4M 2.0 Schema: a general purpose high performance schema for the Accumulo database

LLSuperCloud: sharing HPC systems for diverse rapid prototyping

September 10, 2013
  |
Conference Paper
Author:
Albert I. Reuther
…
Published in:
HPEC 2013: IEEE Conf. on High Performance Extreme Computing, 10-12 September 2013.
Topic:
supercomputing
R&D area:
R&D group:

Summary

The supercomputing and enterprise computing arenas come from very different lineages. However, the advent of commodity computing servers has brought the two arenas closer than they have ever been. Within enterprise computing, commodity computing servers have resulted in the development of a wide range of new cloud capabilities: elastic computing, virtualization, and data hosting. Similarly, the supercomputing community has developed new capabilities in heterogeneous, massively parallel hardware and software. Merging the benefits of enterprise clouds and supercomputing has been a challenging goal. Significant effort has been expended in trying to deploy supercomputing capabilities on cloud computing systems. These efforts have resulted in unreliable, low performance solutions, which requires enormous expertise to maintain. LLSuperCloud provides a novel solution to the problem of merging enterprise cloud and supercomputing technology. More specifically LLSuperCloud reverses the traditional paradigm of attempting to deploy supercomputing capabilities on a cloud and instead deploys cloud capabilities on a supercomputer. The result is a system that can handle heterogeneous, massively parallel workloads while also providing high performance elastic computing, virtualization, and databases. The benefits of LLSuperCloud are highlighted using a mixed workload of C MPI, parallel MATLAB, Java, databases, and virtualized web services.
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Summary

The supercomputing and enterprise computing arenas come from very different lineages. However, the advent of commodity computing servers has brought the two arenas closer than they have ever been. Within enterprise computing, commodity computing servers have resulted in the development of a wide range of new cloud capabilities: elastic computing...

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LLSuperCloud: sharing HPC systems for diverse rapid prototyping

D4M 2.0 Schema: a general purpose high performance schema for the Accumulo database

September 10, 2013
  |
Conference Paper
Author:
Jeremy Kepner
…
Published in:
HPEC 2013: IEEE Conf. on High Performance Extreme Computing, 10-12 September 2013.
Topic:
big data
R&D area:
R&D group:

Summary

Non-traditional, relaxed consistency, triple store databases are the backbone of many web companies (e.g., Google Big Table, Amazon Dynamo, and Facebook Cassandra). The Apache Accumulo database is a high performance open source relaxed consistency database that is widely used for government applications. Obtaining the full benefits of Accumulo requires using novel schemas. The Dynamic Distributed Dimensional Data Model (D4M) [http://www.mit.edu/~kepner/D4M] provides a uniform mathematical framework based on associative arrays that encompasses both traditional (i.e., SQL) and non-traditional databases. For non-traditional databases D4M naturally leads to a general purpose schema that can be used to fully index and rapidly query every unique string in a dataset. The D4M 2.0 Schema has been applied with little or no customization to cyber, bioinformatics, scientific citation, free text, and social media data. The D4M 2.0 Schema is simple, requires minimal parsing, and achieves the highest published Accumulo ingest rates. The benefits of the D4M 2.0 Schema are independent of the D4M interface. Any interface to Accumulo can achieve these benefits by using the D4M 2.0 Schema.
READ LESS

Summary

Non-traditional, relaxed consistency, triple store databases are the backbone of many web companies (e.g., Google Big Table, Amazon Dynamo, and Facebook Cassandra). The Apache Accumulo database is a high performance open source relaxed consistency database that is widely used for government applications. Obtaining the full benefits of Accumulo requires using...

READ MORE
D4M 2.0 Schema: a general purpose high performance schema for the Accumulo database

Slab-coupled optical waveguide (SCOW) devices and photonic integrated circuits (PICs)

September 8, 2013
  |
Conference Paper
Author:
Paul W. Juodawlkis
…
Published in:
2013 IEEE Photonics Conf. (IPC), 8-12 September 2013.
Topic:
photonics
R&D area:

Summary

We review recent advances in the development of slab-coupled optical waveguide (SCOW) devices, progress toward a flexible photonic integration platform containing both conventional high-confinement and SCOW ultra-low confinement devices, and applications of this technology.
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Summary

We review recent advances in the development of slab-coupled optical waveguide (SCOW) devices, progress toward a flexible photonic integration platform containing both conventional high-confinement and SCOW ultra-low confinement devices, and applications of this technology.

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Slab-coupled optical waveguide (SCOW) devices and photonic integrated circuits (PICs)
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