Showing papers by "Raytheon published in 2006"

Tropospheric emission spectrometer: retrieval method and error analysis

Abstract: We describe the approach for the estimation of the atmospheric state, e.g., temperature, water, ozone, from calibrated, spectral radiances measured from the Tropospheric Emission Spectrometer (TES) onboard the Aura spacecraft. The methodology is based on the maximum a posteriori estimate, which mathematically requires the minimization of the difference between observed spectral radiances and a nonlinear model of radiative transfer of the atmospheric state subject to the constraint that the estimated state must be consistent with an a priori probability distribution for that state. The minimization techniques employed here are based on the trust-region Levenberg-Marquardt algorithm. An analysis of the errors for this estimate include smoothing, random, spectroscopic, "cross-state", representation, and systematic errors. In addition, several metrics and diagnostics are introduced that assess the resolution, quality, and statistical significance of the retrievals. We illustrate this methodology for the retrieval of atmospheric and surface temperature, water vapor, and ozone over the Gulf of Mexico on November 3, 2004.

A Tailored Smoking, Alcohol, and Depression Intervention for Head and Neck Cancer Patients

Abstract: Background: Smoking, alcohol use, and depression are interrelated and highly prevalent in patients with head and neck cancer, adversely affecting quality of life and survival. Smoking, alcohol, and depression share common treatments, such as cognitive behavioral therapy and antidepressants. Consequently, we developed and tested a tailored smoking, alcohol, and depression intervention for patients with head and neck cancer. Methods: Patients with head and neck cancer with at least one of these disorders were recruited from the University of Michigan and three Veterans Affairs medical centers. Subjects were randomized to usual care or nurse-administered intervention consisting of cognitive behavioral therapy and medications. Data collected included smoking, alcohol use, and depressive symptoms at baseline and at 6 months. Results: The mean age was 57 years. Most participants were male (84%) and White (90%). About half (52%) were married, 46% had a high school education or less, and 52% were recruited from Veterans Affairs sites. The sample was fairly evenly distributed across three major head and neck cancer sites and over half (61%) had stage III/IV cancers. Significant differences in 6-month smoking cessation rates were noted with 47% quitting in the intervention compared with 31% in usual care ( P < 0.05). Alcohol and depression rates improved in both groups, with no significant differences in 6-month depression and alcohol outcomes. Conclusion: Treating comorbid smoking, problem drinking, and depression may increase smoking cessation rates above that of usual care and may be more practical than treating these disorders separately. (Cancer Epidemiol Biomarkers Prev 2006;15(11):2203–8)

Incident command system

Abstract: A portable electronic command board includes a computer for inputting incident data, a database for storing incident data locally within the computer and a wireless interface, connected to the computer, to connect the computer with another computer to replicate the database on the other computer to provide a collaborative workspace environment. Furthermore a touch screen is provided to input the incident data in a manner similar to drawing on a white board.

Tropospheric Emission Spectrometer observations of the tropospheric HDO/H2O ratio: Estimation approach and characterization

Abstract: [1] We present global, vertical profile estimates of the HDO/H2O ratio from the Tropospheric Emission Spectrometer (TES) on the Earth Observing System (EOS) Aura satellite. We emphasize in this paper the estimation approach and error characterization, which are critical to determining the very small absolute concentration of HDO relative to H2O and its uncertainty. These estimates were made from TES nadir-viewing (downlooking) thermal infrared spectral radiances observed on 20 September 2004. Profiles of HDO and H2O are simultaneously estimated from the observed radiances and a profile of the ratio is then calculated. This simultaneous, or “joint,” estimate is regularized with an a priori covariance matrix that includes expected correlations between HDO and H2O. This approach minimizes errors in the profile of the HDO/H2O ratio that are due to overlapping HDO and H2O spectroscopic lines. Under clear-sky conditions in the tropics, TES estimates of the HDO/H2O ratio are sensitive to the distribution of the actual ratio between the surface and about 300 hPa with peak sensitivity at 700 hPa. The sensitivity decreases with latitude through its dependence on temperature and water amount. We estimate a precision of approximately 1% to 2% for the ratio of the HDO/H2O tropospheric densities; however, there is possibly a bias of approximately 5% in the ratio due to the HDO spectroscopic line strengths. These global observations clearly show increased isotopic depletion of water vapor at higher latitudes as well as increased depletion in the upper troposphere versus the lower troposphere.

Ferrite phase shifter and phase array radar system

Abstract: A phase shifter comprises a substrate, a ground plane formed on a first surface of the substrate, a support structure positioned on a second surface of the substrate opposite the first surface, three parallel, non-co-planar microstrip lines supported by the support structure above the second surface of the substrate, a ferrite element supported by the support structure between the second surface of the substrate and the three non-co-planar microstrip lines, and means for applying a magnetic field to the ferrite element.

The role of CA3 hippocampal NMDA receptors in paired associate learning.

Abstract: The hippocampus is necessary for declarative memory in humans and episodic memory in rodents. Considerable current research is focused on the role of plasticity within specific subfields of the hippocampus. Here, using a viral vector to temporally control a focal deletion of the NR1 gene, we show that learning novel paired associations between specific cues and their context is dependent on CA3 NMDA receptors. Deletion of CA3 NR1 genes in <30% of the dorsal hippocampus was sufficient to disrupt new learning, whereas the same treatment does not prevent expression of previously acquired paired associates and does not affect the ability to discriminate contexts or paired associate learning when either the cues or the context is familiar. The findings suggest that CA3 NMDA receptors specifically support the encoding of new experiences to involve incidental and contingent associations.

Ozone-CO correlations determined by the TES satellite instrument in continental outflow regions

Abstract: 0.4– 1.0 mol mol � 1 and consistent with ICARTT data. The GEOS-Chem model reproduces the O3-CO enhancement ratios observed in continental outflow, but model correlations are stronger and more extensive. We show that the discrepancy can be explained by spectral measurement errors in the TES data. These errors will decrease in future data releases, which should enable TES to provide better information on O3-CO correlations. Citation: Zhang, L., et al. (2006), Ozone-CO correlations determined by the TES satellite instrument in continental outflow regions, Geophys. Res. Lett., 33, L18804, doi:10.1029/2006GL026399.

The Fifth VLBA Calibrator Survey: VCS5

Abstract: This paper presents the fifth part of the Very Long Baseline Array (VLBA) Calibrator Survey (VCS), containing 569 sources not observed previously with very long baseline interferometry in geodetic or absolute astrometry programs. This campaign has two goals: (i) to observe additional sources which, together with previous survey results, form a complete sample, (ii) to find new strong sources suitable as phase calibrators. This VCS extension was based on three 24-hour VLBA observing sessions in 2005. It detected almost all extragalactic flat-spectrum sources with correlated flux density greater than 200 mJy at 8.6 GHz above declination -30 degrees which were not observed previously. Source positions with milliarcsecond accuracy were derived from astrometric analysis of ionosphere-free combinations of group delays determined from the 2.3 GHz and 8.6 GHz frequency bands. The VCS5 catalog of source positions, plots of correlated flux density versus projected baseline length, contour plots and FITS files of naturally weighted CLEAN images, as well as calibrated visibility function files are available on the Web at this http URL

The Visible Infrared Imaging Radiometer Suite

Abstract: The Visible Infrared Imaging Radiometer Suite (VIIRS) is used to obtain measurements of the Earth’s oceans, land surface and atmosphere to make a wide range of Environmental Data Records (EDR’s). These standard products, which have been defined in the Integrated Operational Requirements Document (IORD) (JARG, 2005), are listed in Table 11.1. VIIRS is designed to provide global coverage at least once per day, with moderate (better than 1 km) spatial resolution. This combination of spatial and temporal scales has been chosen to provide needed input to operational weather and environmental models while sampling the natural variability of biological processes on the land surface and in the oceans. It has very high radiometric and geometric fidelity, enabling its use in the acquisition of long-term data records suitable for the study of climate and climate change as well as being a powerful tool for studies designed to increase our understanding of specific geophysical processes such as the interaction of the biological and physical mechanisms in ocean plankton blooms.

Technique for compensation of transmit leakage in radar receiver

Abstract: A radar system (500) radiates a radar transmit signal, has a radar signal receiver (503) and a canceller (505) for canceling leakage of the transmit signal into the radar signal receiver (503). The canceller (505) comprises a digital waveform generator (528) for generating a first digital signal converted to an analog waveform. The analog waveform is amplified after a fixed delay (534) to generate a first cancellation signal input into a circulator (504). The circulator combines the first cancellation signal with the leakage to generate a first corrected signal. A summer (507) combines the first corrected signal from the circulator with a second cancellation signal to generate a second corrected signal. The second cancellation signal is generated by a digital cancellation filter (526). The digital cancellation filter (526) has as an input the first digital signal from the digital waveform generator (528). The digital cancellation filter (526) is controlled using weight adjustments computed by an adaptive weight processor (518). The adaptive weight processor (518) samples the second corrected signal and computes the weight adjustments to optimize the second cancellation signal.

Search for gravitational waves from binary black hole inspirals in LIGO data

Abstract: We report on a search for gravitational waves from binary black hole inspirals in the data from the second science run of the LIGO interferometers. The search focused on binary systems with component masses between 3 and 20M⊙. Optimally oriented binaries with distances up to 1 Mpc could be detected with efficiency of at least 90%. We found no events that could be identified as gravitational waves in the 385.6 hours of data that we searched.

Discovery of Water Maser Emission in Eight AGNs with 70 m Antennas of NASA's Deep Space Network

Abstract: We report the discovery of water maser emission in eight active galactic nuclei (AGNs) with the 70 m NASA Deep Space Network (DSN) antennas at Tidbinbilla, Australia, and Robledo, Spain. The positions of the newly discovered masers, measured with the VLA, are consistent with the optical positions of the host nuclei to within 1 σ (03 radio and 13 optical) and most likely mark the locations of the embedded central engines. The spectra of two sources, NGC 3393 and NGC 5495, display the characteristic spectral signature of emission from an edge-on accretion disk, with orbital velocities of ~600 and ~400 km s-1, respectively. In a survey with DSN facilities of 630 AGNs selected from the NASA Extragalactic Database, we have discovered a total of 15 water maser sources. The resulting incidence rate of maser emission among nearby (vsys < 7000 km s-1) Seyfert 1.8-2.0 and LINER systems is ~10% for a typical rms noise level of ~14 mJy over 1.3 km s-1 spectral channels. As a result of this work, the number of nearby AGNs (vsys < 7000 km s-1) observed with <20 mJy rms noise has increased from 130 to 449.

Airfoil array with an endwall depression and components of the array

Abstract: An airfoil array includes a laterally extending endwall 56 with a series of airfoils such as 28 , or 38 projecting from the endwall. The airfoils cooperate with the endwall to define a series of fluid flow passages 74 . The endwall has a hump 84 toward a pressure side of the passage and a less elevated profile toward a suction side of the passage for reducing secondary flow losses.

Network architecture and communication modules for guaranteeing acceptable control and communication performance for networked multi-agent systems

Abstract: When sensory and actuation devices in a control system are exchanging data through one common communication medium, the sharing of communication bandwidth will induce unavoidable data latency and might degrade the control performance. Hence, the utilization of communication resource and the requirement of control specification should be analyzed and properly designed when implementing a control system over a network architecture. In this paper, we analyze the performance of information sharing of multiple cooperative agents over one communication network, and propose design methodologies of guaranteeing acceptable control and communication performance in a networked control system. In particular, we study the relationship between the sampling rates of a control system,and the transmission rates of a communication network, and then utilize an integrated networked control design chart to help select design parameters and visualize overall system performance at different sampling and transmission rates. Based on the design parameters selected, the communication modules by utilizing deadband control and state estimation are presented for guaranteeing both control and communication performance. Simulation studies are conducted in a network-and-control simulation tool that is developed on the Matlab/Simulink platform and is used to demonstrate the proposed design methodologies. Both the analysis and simulation results illustrate the characteristics of designing mechanisms between control and communication performance and show the improvement of implementing the proposed communication modules.

Generic head models for atlas‐based EEG source analysis

Abstract: We describe a method for using a generic head model, in the form of an anatomical atlas, to produce EEG source localizations. The atlas is fitted to the subject by a nonrigid warp using a set of surface landmarks. The warped atlas is used to compute a finite element model (FEM) of the forward mapping or lead-fields between neural current generators and the EEG electrodes. These lead-fields are used to localize current sources from the subject's EEG data and the sources are then mapped back to the anatomical atlas. This approach provides a mechanism for comparing source localizations across subjects in an atlas-based coordinate system, which can be used in the large fraction of EEG studies in which MR images are not available. The Montreal brain atlas was used as the reference anatomical atlas and 10 individual MR volumes were used to evaluate the method. The atlas was fitted to each subject's head by a thin-plate-spline (TPS) warp. The spatial locations of a generic 155-electrode configuration were used to constrain the warp. For the purposes of evaluation, dipolar sources were placed on the inner cortical surface in the atlas geometry and transferred to each subject's brain space using a polynomial warp. The parameters of the warp were computed using an intensity-based matching of the atlas and subject brains, thus ensuring that the sources were placed at approximately the same anatomical location in each case. Data were simulated in the subject geometry and a dipole fit was performed on these data using an FEM of the TPS warped atlas. The source positions found in the warped atlas were transferred back to the original atlas and compared to the original position. Sources were simulated at 972 locations evenly distributed over the inner cortical surface of the atlas. The mean error over all 10 subjects was 8.1 mm in the subject space and 15.2 mm in the atlas space. In comparison, using an affine transformation of the electrodes into atlas space and an FEM model generated from the atlas produced mean errors of 22.3 mm in subject space and 19.6 mm in atlas space. With a standard three-shell spherical model the errors were 27.2 mm in the subject space and 34.7 mm when mapped to atlas space.

Nadir measurements of carbon monoxide distributions by the Tropospheric Emission Spectrometer instrument onboard the Aura Spacecraft: Overview of analysis approach and examples of initial results

Abstract: We provide an overview of the nadir measurements of carbon monoxide (CO) obtained thus far by the Tropospheric Emission Spectrometer (TES) The instrument is a high resolution array Fourier transform spectrometer designed to measure infrared spectral radiances from low Earth orbit It is one of four instruments successfully launched onboard the Aura platform into a sun synchronous orbit at an altitude of 705 km on July 15, 2004 from Vandenberg Air Force Base, California Nadir spectra are recorded at 006/cm spectral resolution with a nadir footprint of 5 x 8 km We describe the TES retrieval approach for the analysis of the nadir measurements, report averaging kernels for typical tropical and polar ocean locations, characterize random and systematic errors for those locations, and describe instrument performance changes in the CO spectral region as a function of time Sample maps of retrieved CO for the middle and upper troposphere from global surveys during December 2005 and April 2006 highlight the potential of the results for measurement and tracking of global pollution and determining air quality from space

N-BIT 2's COMPLEMENT SYMMETRIC ROUNDING METHOD AND LOGIC FOR IMPLEMENTING THE SAME

Abstract: A rounding circuit is provided that includes an input for receiving a 2's complement number to be rounded. The 2's complement number has a format SXY, where S represents a sign bit, X represents one or more bits to round and keep, and Y represents one or more bits to be discarded. The rounding circuit also includes first logic for adding a rounding bias to the 2's complement number, and second logic for at least one of subtracting the sign bit S from the 2's complement number, or adding the inverted sign bit !S to the 2's complement number. Moreover, the rounding circuit includes third logic for truncating Y bits from a result produced by the first and second logic to produce a rounded 2's complement number having a format SX.

Western Pacific modulation of large phytoplankton blooms in the central and eastern equatorial Pacific

Abstract: [1] Satellite observations show that large-scale phytoplankton blooms (increases in chlorophyll) occurred in the equatorial Pacific in 1998, 2003, and 2005, following termination of the three most recent El Nino events. The occurrence of blooms following successive El Nino events cannot be explained by local enhancement of vertical nutrient flux, as evidenced by observations of equatorial winds, thermocline depth, and the depth and strength of the Equatorial Undercurrent (EUC, which supplies the limiting nutrient iron to the euphotic zone). However, near the peak of each El Nino event (late in 1997, 2002, and 2004), while the thermocline of the western equatorial Pacific was anomalously shallow, the flow of the New Guinea Coastal Undercurrent (NGCUC, which is the primary source of iron-enriched waters to the EUC) intensified, and its core shoaled from >200 m to ∼100 m depth. Analysis of NGCUC variability using a high-resolution, terrain-following three-dimensional ocean circulation model simulation indicates that as the NGCUC shoals and intensifies, it develops meanders and eddies that augment coupling of the New Guinea shelf and upper slope to the EUC. We hypothesize that these changes in NGCUC circulation during El Nino enhance iron transport from the New Guinea margin into the EUC and thereby trigger large-scale blooms when iron-enriched waters subsequently reach the euphotic zone along the equator. The threefold to fourfold chlorophyll increases over large regions, up to ∼5 × 105 km2, must have profound impacts on the equatorial ecosystem and biogeochemical cycles.

Passive conductive cooling module

Abstract: A cooling module includes a thermally conductive plate, a bladder disposed on at least one side of the plate, the bladder have a chamber, and fluid disposed in the chamber of the bladder wherein the bladder in an inflated state impresses the cooling module against an adjacent electronic circuit card. where the cooling module is forcibly pressed against adjacent electronic circuit card providing increased physical stability to the electronic circuit card as well as provide a cooling technique for the circuit card.

A method of generating accurate estimates of azimuth and elevation angles of a target for a phased-phased array rotating radar

Abstract: A method and apparatus for generating accurate estimates of a radar target ' s azimuth and elevation angles for a phased-phased array rotating radar. Scan modulated coherently integrated (SMCI) monopulse curves are generated from a measured one-way transmit antenna pattern and three receive antenna patterns . The SMCI monopulse curves are calculated in advance for the expected beam steers. To utilize the SMCI monopulse curves, two-way Sum, Delta-Azimuth and Delta-Elevation target returns are coherently integrated, the target's monopulse ratios calculated, and the SMCI monopulse curves or polynomials used to calculate the target's U- of f set and V-offset sine-space angles, which are added to the radar's beam steer to get an improved estimate of the target's sine-space angular position denoted as Utgt and Vtgt- A coordinate system transformation transforms Utgt and Vtgt to azimuth and elevation angles in a non- rotating coordinate system.

Uninterruptible oil supply in planetary system

Abstract: A planetary carrier includes a journal bearing for supporting a planetary gear. The journal bearing receives lubricant to produce a lubricant film to support gear loads. A torque frame is attached to the carrier housing to transmit torque and to prevent twisting of the carrier housing. The torque frame includes several lubricant communication passages to provide lubricant to each of the separate journal bearings. Each of the lubricant communication passages includes an accumulator for storing lubricant during normal operation. The accumulator stores a desired amount of lubricant to provide lubricant to the adjacent journal bearing for the interim period between primary system stoppage and reestablishment of lubricant flow by a secondary system.

Integrated smart power switch

Abstract: A device including a controllable semiconductor, sensor, and controller is provided. The controllable semiconductor is associated with a first operating parameter and a second operating parameter, wherein at least the first operating parameter is controllable. The sensor is in communication with the controllable semiconductor device and acquires data relating to the second operating parameter of the controllable semiconductor device. The controller is in communication with the controllable semiconductor device and the sensor, and the controller is configured to access device data associated with the controllable semiconductor, control the first operating parameter of the controllable semiconductor, and receive data from the first sensor relating to the second operating parameter. The controller determines a first predicted value dependent on the device data, compares the data relating to the second operating parameter with the first predicted value, and, if a first condition is detected based on this comparison, dynamically modifies the first operating parameter.

Applying System Execution Modeling Tools to Evaluate Enterprise Distributed Real-time and Embedded System QoS

Abstract: Component middleware is popular for enterprise distributed systems because it provides effective reuse of the core intellectual property (i.e., the "business logic"). Component-based enterprise distributed real-time and embedded (DRE) systems, however, incur new integration problems associated with component configuration and deployment. New research is therefore needed to minimize the gap between the development and deployment/ configuration of components, so that deployment and configuration strategies can be evaluated well before system integration. This paper uses an industrial case study from the domain of shipboard computing to show how system execution modeling tools can provide software and system engineers with quantitative estimates of system bottlenecks and performance characteristics to help evaluate the performance of componentbased enterprise DRE systems and reduce time/effort in the integration phase. The results from our case study show the benefits of system execution modeling tools and pinpoint where more work is needed.

Ceramic shroud assembly

Abstract: A ceramic shroud assembly suitable for use in a gas turbine engine comprises a metal clamp ring shrink fitted around a ceramic shroud ring and an insulating and compliant interlayer. The interlayer is positioned between the metal clamp ring and the ceramic shroud ring.

Beam director and control system for a high energy laser within a conformal window

Abstract: A beam control system and method. The system includes an illuminator for providing a first beam of electromagnetic energy at a first wavelength; a source for providing a second beam of electromagnetic energy at a second wavelength; and an arrangement for compensating wavefront errors in the second beam using a bias representative of a comparison between the first wavelength and the second wavelength. In the illustrative embodiment, the arrangement includes a processor which corrects wavefront errors using a bias representative of a difference between said first wavelength and said second wavelength. In the disclosed application, a target wavefront sensor is included and the laser is a high-energy laser beam. The wavefront errors include a chromatic aberration and the errors are compensated using a deformable mirror and a correction algorithm executed by an adaptive optics processor. In one alternative embodiment, the errors are compensated using an optical aberration corrector. The aberration corrector may be a holographic optical element or other suitable device. In another alternative embodiment, the errors are corrected with the above embodiment in combination with the use of “woofer” and “tweeter” correcting elements with the woofer being a long stroke low frequency element and the tweeter being a short stroke high frequency element.

Phased-Array and Radar Breakthroughs

Abstract: Many think that radar is a mature field, nothing new to happen, it having been around a long time. Nothing can be further from the truth. When I entered the field in the '50s I thought the same thing. The MIT Radiation Lab. Series 28 book volume set summarizing the highly classified World War II work on radar was just published and provided the definitive coverage and there was to be nothing more to learn. How wrong I was. Since then many amazing new developments have taken place. Things are moving even faster now. We live in exciting times. Phased array radars and radars have seen in recent years breakthroughs that lead to capabilities not possible only a few years ago. This is exemplified by the development of GaAs integrated microwave circuits called monolithic microwave integrated circuits (MMIC) which makes it possible to build active electronically scanned arrays (AESAs) having lighter weight, smaller volume, higher reliability and lower cost. MMIC allows the construction of AESAs for applications not feasible before. This integration has reached the point where it is possible to now build a low cost 35 GHz phased array for a missile seeker costing $40/element (total cost of array including all electronics divided by number of elements). The advances provided by Moore's Law has now made it is feasible to do digital beam forming with all its numerous advantages. One advantage of digital beamforming is the ability to lower the search power and occupancy by up to a factor of two. Another advantage is that it makes it possible to achieve the performance of a fully adaptive array without having to do a large matrix inversion, i.e., it makes adaptive-adaptive array processing or equivalently principal decomposition feasible. Also covered will be: the potential for GaN and SiC chips which have the capability of a factor of ten higher peak power than GaAs chips; arrays with instantaneous bandwidths of up to 33:1; SiGe low cost T/R modules; low cost MEMS arrays; metamaterials which provide negative refractivity possibly allowing focusing beyond the diffraction limit; a real radar application for Multiple-Input Multiple-Output (MIMO) as opposed to fantasy has been demonstrated by Lincoln Laboratory MIT which allows the coherent combining of two radars to achieve a 9 dB increase in sensitivity; the ability to build microwave tubes that are smaller, more power efficient, lighter, require lower voltages and have lower cost.

A classification system for radar and sonar applications

Abstract: The invention lies in the field of digital airport surveillance and overcomes a problem in identifying various types of aircraft and non- aircraft targets The invention relates to an apparatus and a method for classifying a given radar track segment obtained from multiple radars wherein the method comprises of a pre-processing stage to form the given radar track segment and to generate principal/secondary track data, a feature extraction stage to process the principal/secondary track data, a classification stage that generates principal and extension classification results for the given radar track segment based on feature values, and a combiner stage that combines the extension and principal classification results to provide a classification result for the given radar track segment.

Repair of composite sandwich structures

Abstract: A method of restoring a section of a composite includes the steps of removing an undesirable section of a composite and securing a repair section in the location of the removed undesirable section. One or more covers are secured on at least a portion the repair section to prevent or resist peeling of the repair section.