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Anatomy of a SAR impulse response

Doerry, Armin

A principal measure of Synthetic Aperture Radar (SAR) image quality is the manifestation in the SAR image of a spatial impulse, that is, the SAR's Impulse Response (IPR). IPR requirements direct certain design decisions in a SAR. Anomalies in the IPR can point to specific anomalous behavior in the radar's hardware and/or software.

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TYPE SAND Report YEAR 2007
DOIOSTI

Updated laser safety & hazard analysis for the ARES laser system based on the 2007 ANSI Z136.1 standard

Augustoni, Arnold L.

A laser safety and hazard analysis was performed for the temperature stabilized Big Sky Laser Technology (BSLT) laser central to the ARES system based on the 2007 version of the American National Standards Institutes (ANSI) Standard Z136.1, for Safe Use of Lasers and the 2005 version of the ANSI Standard Z136.6, for Safe Use of Lasers Outdoors. The ARES laser system is a Van/Truck based mobile platform, which is used to perform laser interaction experiments and tests at various national test sites.

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TYPE SAND Report YEAR 2007
DOIOSTI

Microenergetics : combustion and detonation at sub-millimeter scales

Tappan, Alexander S.

At Sandia National Laboratories, we have coined the term 'microenergetics' to describe sub-millimeter energetic material studies aimed at gaining knowledge of combustion and detonation behavior at the mesoscale. Our approach is to apply technologies developed by the microelectronics industry to fabricate test samples with well-defined geometries. Substrates have been fabricated from materials such as silicon and ceramics, with channels to contain the energetic material. Energetic materials have been loaded into the channels, either as powders, femtosecond laser-micromachined pellets, or as vapor-deposited films. Ignition of the samples has been achieved by simple hotwires, integrated semiconductor bridges, and also by lasers. Additionally, grain-scale patterning has been performed on explosive films using both oxygen plasma etching and femtosecond laser micromachining. We have demonstrated simple work functions in microenergetic devices, such as piston motion, which is also a relevant diagnostic to examine combustion properties. Detonation has been achieved in deposited explosive films, recorded by high-speed photography. A review of progress on manufacturing and testing will be presented, as well as historical perspectives and future directions.

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TYPE Conference YEAR 2007
OSTI

Spectrum Imaging Approaches for Bioforensics

Sandia journal manuscript; Not yet accepted for publication

Ohlhausen, J.A.; Kotula, Paul G.; Michael, Joseph R.

Spectrum imaging combined with multivariate statistics is an approach to microanalysis that makes the maximum use of the large amount of data potentially collected in forensics analysis. Here, this study examines the efficacy of using spectrum imaging-enabled microscopies to identify chemical signatures in simulated bioagent materials. This approach allowed for the ready discrimination between all samples in the test. In particular, the spectrum imaging approach allowed for the identification of particles with trace elements that would have been missed with a more traditional approach to forensic microanalysis. Finally, the importance of combining signals from multiple length scales and analytical sensitivities is discussed.

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TYPE Journal Article YEAR 2007
OSTI

Product acceptance environmental and destructive testing for reliability

Collins, Elmer W.; Kerschen, Thomas J.; Dvorack, Michael A.

To determine whether a component is meeting its reliability requirement during production, acceptance sampling is employed in which selected units coming off the production line are subjected to additional environmental and/or destructive tests that are within the normal environment space to which the component is expected to be exposed throughout its life in the Stockpile. This report describes what these tests are and how they are scored for reliability purposes. The roles of screens, Engineering Use Only tests, and next assembly product acceptance testing are also discussed, along with both the advantages and disadvantages of environmental and destructive testing.

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TYPE SAND Report YEAR 2007
DOIOSTI

Making the giant leap with augmented cognition technologies : what will be the first %22killer app?'

Forsythe, James C.

This paper highlights key topic areas to be discussed the authors in a panel format during the Augmented Cognition thematic area paper session: 'Augmented Cognition Lessons Learned and Future Directions for Enabling 'Anyone, Anytime, Anywhere' Applications'. The term 'killer app' has been part of the vernacular in the commercial computer software and electronic devices industry to refer to breakthrough technologies [2]. A 'killer app' generally emerges with the development of related technologies that extends over some time and involves numerous variations on a basic concept. Hypotheses may be offered with respect to the conditions that will be needed to enable a similar situation with augmented cognition technologies. This paper and resulting panel session will address the numerous concepts that have emerged from the augmented cognition field to date and postulate how and when this field's first 'killer app' may emerge (e.g., 5, 10, 15, or more years from now).

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TYPE Conference YEAR 2007
OSTI

Molten salt-based growth of bulk GaN and InN for substrates

Waldrip, Karen E.

An atmospheric pressure approach to growth of bulk group III-nitrides is outlined. Native III-nitride substrates for optoelectronic and high power, high frequency electronics are desirable to enhance performance and reliability of these devices; currently, these materials are available in research quantities only for GaN, and are unavailable in the case of InN. The thermodynamics and kinetics of the reactions associated with traditional crystal growth techniques place these activities on the extreme edges of experimental physics. The novel techniques described herein rely on the production of the nitride precursor (N{sup 3-}) by chemical and/or electrochemical methods in a molten halide salt. This nitride ion is then reacted with group III metals in such a manner as to form the bulk nitride material. The work performed during the period of funding (February 2006-September 2006) focused on establishing that mass transport of GaN occurs in molten LiCl, the construction of a larger diameter electrochemical cell, the design, modification, and installation of a made-to-order glove box (required for handling very hygroscopic LiCl), and the feasibility of using room temperature molten salts to perform nitride chemistry experiments.

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TYPE SAND Report YEAR 2007
DOIOSTI
Results 78901–79000 of 96,771
Results 78901–79000 of 96,771