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This research addressed the USAF s unprecedented proactive persistent surveillance Long Term Challenge. Specifically, we aimed at a substantial enhancement of the ability to conduct autonomous, video based, persistent intelligent surveillance, reconnaissance and threat assessment in highly uncertain, adversarial scenarios such as urban environments. At its core was a novel approach, stressing dynamic models as key enablers for finding, tracking and anticipating/assessing behavior of multiple targets using as inputs data streams from spatially distributed sensors. It included both theory developments in an emerging new field dynamics based extraction of information sparsely encoded in high dimensional data and an investigation of implementation issues., The original document contains color images.

The low-frequency target strength of shoaling Atlantic herring (Clupea harengus) in the Gulf of Maine during Autumn 2006 spawning season is estimated from experimental data acquired simultaneously at multiple frequencies in the 300 1200 Hz range using (1) a low-frequency ocean acoustic waveguide remote sensing (OAWRS) system, (2) areal population density calibration with several conventional fish finding sonar (CFFS) systems and (3) low-frequency transmission loss measurements. The OAWRS system s instantaneous imaging diameter of 100 km and regular updating enabled unaliased monitoring of fish populations over ecosystem scales including shoals of Atlantic herring containing hundreds of millions of individuals, as confirmed by concurrent trawl and CFFS sampling. High spatial-temporal coregistration was found between herring shoals imaged by OAWRS and concurrent CFFS line-transects, which also provided fish depth distributions. The mean scattering cross-section of an individual shoaling herring is found to consistently exhibit a strong, roughly 20 dB/octave roll-off with decreasing frequency in the range of the OAWRS survey over all days of the roughly 2-week experiment, consistent with the steep roll-offs expected for sub-resonance scattering from fish with air-filled swimbladders., Published in the Journal of the Acoustical Society of America, v127 n1, Jan 2010. Sponsored in part by NOPP and NOAA.

The central goal of this project was the investigation of the enhancements in antenna performance and in imaging capability by embedding a source or scatterer in a background medium including metamaterials. This effort was motivated mostly by the possibility of embedding antennas in designer background media so as to obtain radiation performance that would not be possible for comparable antennas in free space. This problem was treated in the present work within a general and non-device-specific framework whose predictions (such as performance bounds) under normalized resources are fundamental. The results were discussed addressing separately the cases of small versus large or resonant antennas, with the overall conclusion that for small antennas one can significantly enhance the radiated power or compress source size via antenna substrates under normalized antenna resources, while for larger antennas the use of substrates can significantly enhance both radiated power and directivity (related to the number of essentially independent field modes that can be radiated effectively) under the given resources.

This document constitutes the final project report for Contract # FA9550-04-1-0187 titled Theory and Applications of Computational Time-reversal Imaging. The report summarizes the theoretical development and implementation of time-reversal based imaging and target detection algorithms for locating targets from multistatic data collected from unstructured phased antenna arrays. The report summarizes the main theoretical results obtained in the program and includes both computer simulated examples as well as results from experimental data collected by a research team from Carnegie Mellon University illustrating the use of the algorithms developed in the project. The final section of the report outlines goals for follow-on research in these general areas.

To increase the targeting potential, circulation time, and the flexibility of surface-attached biomedically-relevant ligands on gold nanoparticles, hetero-bifunctional poly(ethylene glycol) (PEG, MW 1,500) was synthesized having a thiol group on one terminus and reactive functional group on the other. Coumarin, a model fluorescent dye, was conjugated to the PEG spacer and gold nanoparticles were modified with coumarin-PEG-thiol. Surface attachment of coumarin through the PEG spacer decreases the fluorescence quenching effect of gold nanoparticles. The results of cellular cytotoxicity and fluorescence confocal analyses showed that the PEG spacer modified nanoparticles were essentially non-toxic and could be efficiently internalized in the cells within one hour of incubation., Presented at the Nanoscale Materials Science in Biology and Medicine held in Boston, MA on 28 Nov-2 Dec 2004. Pub. in Materials Research Society Symposium Proceedings, v845 p223-228, 2005. ISBN 1-55-899-793-8. This article is from ADA434631 Materials Research Society Symposium Proceedings. Volume 845, 2005. Nanoscale Materials Science in Biology and Medicine, Held in Boston, MA on 28 November-2 December 2004

Energy usage is becoming an increasingly important design constraint for all computer systems. This issue is particularly critical in battery powered, embedded designs. Although many embedded processors have developed sophisticated power management schemes, few have produced an accurate, easy-to-use energy estimation framework. In this presentation we will describe the development of an instruction-level energy modeling framework for the Analog Devices Blackfin family of processors. Using this model, we are able to accurately estimate the energy consumed when running this code. While our main goal is to demonstrate that we can perform accurate energy estimation, we also plan to develop a framework that is fully integrated with compilation in order to produce more energy-efficient binaries. In this abstract we briefly describe our methodology and show data that illustrate some of the difficulties encountered when attempting to statically model energy., See also ADM001742. Presented at the Annual High Performance Embedded Computing (HPEC) Workshops (8th) held in Lexington, MA on 28-30 Sep 2004. HPEC-7-VOL-REV. The original document contains color images. Briefing charts only. The original document contains color images. Prepared in cooperation with Analog

Division and square root are important operations in many high performance signal processing applications including matrix inversion, vector normalization, least squares lattice filters and Cholesky decomposition. We have implemented floating point division and square root designs for our VHDL variable precision floating point library. These designs are implemented in VHDL and are designed to make efficient use of FPGA hardware. Both the division 1 and square root 2 algorithms are based on table lookup and Taylor series expansion. These algorithms are particularly well-suited for implementation on an FPGA with embedded RAM and embedded multipliers such as the Altera Stratic and Xilinx Virtex2 devices. The division and square root components have been incorporated into the framework of our variable precision floating-point library., See also ADM001742. Presented at the Annual High Performance Embedded Computing (HPEC) Workshops (8th) held in Lexington, MA on 28-30 Sep 2004. HPEC-7-VOL-1-REV. The original document contains color images. Briefing charts only.

Systems using Field Programmable Gate Array (FPGA) boards have been proven effective for gaining one to three orders of magnitude speed-up over systems based solely on PCs. Signal and image processing applications are especially attractive for implementation on FPGAs as their computationally intensive and massively parallel algorithms can effectively take advantage of the FPGA architecture. In moving part of an algorithm to hardware, one must consider overhead costs as well as the improvement in the computation to determine whether the move will result in overall system speed-up. Dynamo is a runtime system for generating hardware/software pipeline implementations. Dynamo balances the benefits of hardware and software implementations and takes overhead costs into account in order to accurately predict runtimes of hardware/software systems., See also ADM001742, Proceedings of the Annual High Performance Embedded Computing (HPEC) Workshop (8th), 28-30 Sep 2004. Prepared in cooperation with College of the Holy Cross, Worcester, MA. The original document contains color images.

Three-Dimensional Finite-Difference Time-Domain (3D FDTD) is a powerful method for modelling the electromagnetic field. The 3D FDTD buried object detection forward model is emerging as a useful application in mine detection and other subsurface sensing areas. However, the computation of this model is complex and time consuming. Implementing this algorithm in hardware will greatly increase its computational speed and widen its use in many other areas. We present an FPGA implementation to speedup the pseudo-2D FDTD algorithm which is a simplified version of the 3D FDTD model. The pseudo-2D model can be upgraded to 3D with limited modification of structure. We implement the pseudo-2D FDTD model and complete boundary conditions on an FPGA. The computational speed on the reconfigurable hardware is about three orders of magnitude faster than the software implementation. Understanding and predicting electromagnetic behavior is more and more needed in key electrical engineering technologies such as cellular phones, mobile computing, lasers and photonic circuits 2. After K. Yee first introduce the FDTD method in 1966, people began to realize its accuracy and flexibility for solving electromagnetic problems 1. The FDTD method provides a direct time-domain solution of Maxwell s Equations in differential form by discretizing both the physical region and time interval using a uniform grid. Because this method can solve Maxwell s equations on any scale with almost all kinds of environments, it has become a powerful method for solving a wide variety of different electromagnetic problems 3., See also ADM001694, HPEC-6-Vol 1 ESC-TR-2003-081; High Performance Embedded Computing (HPEC) Workshop (7th)., The original document contains color images.

Multimedia architectures can speed-up applications significantly when programmed manually. Optimized programs have been non-portable up to now, because of differences in instruction sets, register lengths, alignment requirements and programming styles. We solve all these problems by using a library of C pre-processor macros called MMM. We implemented three examples from video compression in MMM, and automatically translated them into optimized code for four distinct multimedia processors. Their performance is comparable, and in several cases better, than equivalent examples optimized by the processor vendors., See also ADM001694. Published in HPEC-6-Vol 1 ESC-TR-2003-081. High Performance Embedded Computing (HPEC) Workshop (7th) held on 23-25 Sep 2004. The original document contains color images.

The problem of detecting and classify buried objects situ electromagnetic induction (EMI) sensing technologies has received considerable attention in recent years in a range of application areas including unexploded ordinance (UXO) and landmine remediation. In the last decade or so, considerable advances have been made in the area of EMI instrumentation yielding sensors capable of providing data both in the time and frequency domains which convey far more information concerning the structure of buried objects than is the case with older metal detectors.

Viewgraphs on presentation of parameterized hardware modules for floating point arithmetic and its uses., See also ADM001473. The original document contains color images. Presented at High Performance Embedded Computing (HPEC) Workshop (6th) held in Lexington, MA on 24-26 Sep 2002.

This project was focused on a formal framework for analyzing and developing information fusion systems. Category theory was selected as the formal basis for specifying information fusion systems. A formal definition of information fusion was introduced. Various kinds of fusion were defined, their properties and inter-relationships analyzed. An initial ontology of information fusion was presented. A procedure for developing information fusion systems using formal methods was proposed. Examples of reasoning about measures of effectiveness of information fusion systems were shown. Towards this goal fuzzy logic was formally specified in the Slang language and properties of information fusion were proved. This showed that within this formal framework one can reason about the system being developed in the specification and design phases, rather than after deployment. Finally, the selection of wavelet based features for ATR was investigated within the formal framework.

We propose to study the appropriate wake environment and support the development of detectors for the Charge Hazards and Wake Studies (CHAWS) Missions. Both computer simulations of the detector and laboratory calibrations will be performed. The proposed detector will consist of a high energy resolution Retarding Potential Energy Analyzer and a high spatial resolution drift chamber with MicroChannel Plates. The electric field inside the detector is designed such that the one-to-one correspondence between the incident ion and the collected signal is guaranteed. A fluid dynamic model will be set up to study the effect of the secondary electron, the backscattering, and the negative ion trapping on the potential profile and ion trajectories in the wake. The results of the fluid dynamic model will be compared to hat from the other models. The CHAWS results will be analyzed based on the simulation, including the secondary effects and the time evolution of the plasma parameters. The position of the probes and the operational time sequence of these probes will be modified for best performance.

We have performed in situ measurements in two low frequency CFAs to study several basic physics issues which may lead to CFA noise reduction. Our measurements include the local radio-frequency (RF) fields, electron density profiles, electron energy distributions and noise spectrums in both the linear CFA and the reentrant CFA. Comprehensive electron density measurements of the interaction region as well as parametric comparisons such as gain versus sole voltage, beam current and frequency have been used to benchmark two computer simulation codes, MASK and NESSP.

This final report summarizes a three year project in the area of robust H to infinity control, based mostly on the time domain / game theoretic approach, previously developed by the author. Areas covered included: (1) A framework for sampled data control, including optimization of sample and hold components; (2) lnvestigatir!g fundamental ties between the time and the frequency domain / Hardy space approaches, including control based proofs and variants of the Nehari and Beurling Lax theorems, factorization techniques, dichotomy, etc.; (3) Robust identification and control of periodic and closed to periodic systems; (4) Computationally feasible Robust control of delay systems; (5) Robust system identification; (6) H to infinity based design for frequency varied passivity; and (7) Nliscl. The research resulted both in novel design methods for robust control and in solidifying the theoretical basis of this methodology.

We have developed a theoretical analysis of the current scaling issues of a negatively biased probe in a plasma wake. The theoretical assumptions have been analyzed qualitatively and quantitatively by the use of the POLAR computer code. For a plasma with a constant beam energy, the analysis shows that the I-V collection characteristics are unaffected by Mach number variations for Mach numbers above the value of two. For the same case, the current was found to scale with the 3/7 power of the density.