NASA Scientific and Technical Aerospace Reports

20060001925 Princeton Univ., NJ USA
Nano-Patterned Quantum Structures for Infrared Detection
Tsui, Daniel C.; Sep. 30, 2005; 16 pp.; In English; Original contains color illustrations
Contract(s)/Grant(s): F29601-02-C-0267; Proj-4846
Report No.(s): AD-A440596; AFRL-VS-PS-TR-2005-1192; No Copyright; Avail.: Defense Technical Information Center
(DTIC)
This is the final report of work accomplished under contract #F29601-02-C-0267 from the Air Force Research Laboratory
(Kirtland), which was a three-year research project with two focused objectives: To develop voltage tunable two-color
superlattice QWIPs and broadband QWIPs, and to fabricate quantum-dot QWIPs using nano-patterning and to investigate their
infrared detection characteristics arising from the three-dimensional confinement of electrons in the semiconductor device
structure. The project was funded from October 2002 to July 2004, approximately 2/3 of the originally agreed 3 years.
Consequently, part of the second objective was not reached. More specifically, the nano-patterned quantum-dot QWIPs were
fabricated, but their infrared detection characteristics were not investigated.
DTIC
Infrared Detectors; Nanostructures (Devices); Photometers
20060002490 Duke Univ., Durham, NC USA
Sensor Placement for Grid Coverage Under Imprecise Detections
Dhillon, Santpal S.; Chakrabarty, Krishnendu; Iyengar, S. S.; Jan. 1, 2005; 8 pp.; In English; Original contains color
illustrations
Contract(s)/Grant(s): N00014-01-1-0712; N66001-00-1-8946
Report No.(s): AD-A440417; No Copyright; Avail.: Defense Technical Information Center (DTIC)
We present a resource-bounded optimization framework for sensor resource management under the constraints of
sufficient grid coverage of the sensor field. We offer a unique ‘minimalistic’ view of distributed sensor networks in which
sensors transmit/report a minimum amount of sensed data. The proposed theory is aimed at optimizing the number of sensors
and determining their placement to support such minimalistic sensor networks. We represent the sensor field as a grid (twoor
three-dimensional) of points. The optimization framework is inherently probabilistic due to the uncertainty associated with
sensor detections. The proposed algorithm addresses coverage optimization under constraints of imprecise detections and
terrain properties. The issue of preferential coverage of grid points (based on relative measures of security and tactical
importance) is also modeled. Experimental results for an example sensor field with obstacles demonstrate the application of
our approach.
DTIC
Algorithms; Detection
36
LASERS AND MASERS
Includes lasing theory, laser pumping techniques, maser amplifiers, laser materials, and the assessment of laser and maser outputs.
For cases where the application of the laser or maser is emphasized see also the specific category where the application is treated. For
related information see also 76 Solid-State Physics.
20060001782 Air Force Research Lab., Kirkland AFB, NM USA
Simulation of Flow Unsteadiness in Chemical Oxygen-Iodine Laser Devices
Madden, Timothy J.; Jul. 8, 2005; 32 pp.; In English; Original contains color illustrations
Contract(s)/Grant(s): Proj-4866
Report No.(s): AD-A440193; AFRL-DE-PS-TR-2005-1120; No Copyright; Avail.: Defense Technical Information Center
(DTIC)
3-dimensional Navier-Stokes simulations of chemical oxygen-iodine laser (COIL) hardware are performed to elucidate
the unsteady fluid dynamic aspects of these flowfields. Reacting (COIL) and non-reacting flow simulations are performed on
varying resolution grids to explore the unsteadiness, and comparisons to experimental data are made.
DTIC
Chemical Lasers; Chemical Oxygen-Iodine Lasers; Simulation; Unsteady Flow
89