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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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NASA NTRS2009

NASA Tech Briefs, May 2009

Topics covered include: Valve-"Health"-Monitoring System; Microstrip Antenna for Remote Sensing of Soil Moisture and Sea Surface Salinity; Biomedical Wireless Ambulatory Crew Monitor; Wireless Avionics Packet to Support Fault Tolerance for Flight Applications; Aerobot Autonomy Architecture; Submillimeter Confocal Imaging Active Module; Traveling-Wave Maser for 32 GHz; System Synchronizes Recordings from Separated Video Cameras; Piecewise-Planar Parabolic Reflectarray Antenna; Reducing Interference in ATC Voice Communication; EOS MLS Level 1B Data Processing, Version 2.2; Auto-Generated Semantic Processing Services; Geospatial Authentication; Maneuver Automation Software; Event Driven Messaging with Role-Based Subscriptions; Estimating Relative Positions of Outer-Space Structures; Fabricating PFPE Membranes for Capillary Electrophoresis; Linear Actuator Has Long Stroke and High Resolution; Installing a Test Tap on a Metal Battery Case; Fabricating PFPE Membranes for Microfluidic Valves and Pumps; Room-Temperature-Cured Copolymers for Lithium Battery Gel Electrolytes; Catalysts for Efficient Production of Carbon Nanotubes; Amorphous Silk Fibroin Membranes for Separation of CO2; "Zero-Mass" Noninvasive Pressure Transducers; Radial-Electric-Field Piezoelectric Diaphragm Pumps; Ejector-Enhanced, Pulsed, Pressure-Gain Combustor; Suppressing Ghost Diffraction in E-Beam-Written Gratings; Target-Tracking Camera for a Metrology System; Polarimetric Imaging using Two Photoelastic Modulators; Miniature Wide-Angle Lens for Small-Pixel Electronic Camera; Modal Filters for Infrared Interferometry; Mo(3)Sb(7-x)Te(x) for Thermoelectric Power Generation; Two-Dimensional Quantum Model of a Nanotransistor; Scanning Miniature Microscopes without Lenses; Manipulating Neutral Atoms in Chip-Based Magnetic Traps; Expansion Compression Contacts for Thermoelectric Legs; Processing Electromyographic Signals to Recognize Words; Physical Principle for Generation of Randomness; DSN Beowulf Cluster-Based VLBI Correlator; Hybrid NN/SVM Computational System for Optimizing Designs; Criteria for Modeling in LES of Multicomponent Fuel Flow; Computerized Machine for Cutting Space Shuttle Thermal Tiles; Orbiting Depot and Reusable Lander for Lunar Transportation; FPGA-Based Networked Phasemeter for a Heterodyne Interferometer; Aquarius Digital Processing Unit; Three-Dimensional Optical Coherence Tomography; Benchtop Antigen Detection Technique using Nanofiltration and Fluorescent Dyes; Isolation of Precursor Cells from Waste Solid Fat Tissue; Identification of Bacteria and Determination of Biological Indicators; Further Development of Scaffolds for Regeneration of Nerves; Chemically Assisted Photocatalytic Oxidation System; Use of Atomic Oxygen for Increased Water Contact Angles of Various Polymers for Biomedical Applications; Crashworthy Seats Would Afford Superior Protection; Open-Access, Low-Magnetic-Field MRI System for Lung Research; Microfluidic Mixing Technology for a Universal Health Sensor; Microfluidic Extraction of Biomarkers using Water as Solvent; Microwell Arrays for Studying Many Individual Cells; Droplet-Based Production of Liposomes; and Identifying and Inactivating Bacterial Spores

Source record↗

NASA NTRS1991

Variant terminology

A system called Variant Terminology Switching (VTS) is set forth that is intended to provide computer-assisted spellings for terms that have American and British versions. VTS is based on the use of brackets, parentheses, and other symbols in conjunction with letters that distinguish American and British spellings. The symbols are used in the systems as indicators of actions such as deleting, adding, and replacing letters as well as replacing entire words and concepts. The system is shown to be useful for the intended purpose and also for the recognition of misspellings and for the standardization of computerized input/output. The VTS system is of interest to the development of international retrieval systems for aerospace and other technical databases that enhance the use by the global scientific community.

Buchan, Ronald L.↗

NASA NTRS1974

Selected reliability studies for the NERVA program

An investigation was made into certain methods of reliability analysis that are particularly suitable for complex mechanisms or systems in which there are many interactions. The methods developed were intended to assist in the design of such mechanisms, especially for analysis of failure sensitivity to parameter variations and for estimating reliability where extensive and meaningful life testing is not feasible. The system is modeled by a network of interconnected nodes. Each node is a state or mode of operation, or is an input or output node, and the branches are interactions. The network, with its probabilistic and time-dependent paths is also analyzed for reliability and failure modes by a Monte Carlo, computerized simulation of system performance.

Hoover, S. V.↗

NASA NTRS2003

RSRM Case Acceptance and Refurbishment Requirements

The RSRM (Reuseable Solid Rocket Motor) Program has been developed and implemented to support manned flight space travel. The Space Shuttle Vehicle utilizes two SRBs (Solid Rocket Boosters) to assist during the launch sequence and achieve the predefined orbit and mission objectives. A critical feature of this program involves post- flight SRB retrieval, disassembly and reuse of case structural components to manufacture future RSRM motors. To ensure these components can be safely reused, inspection criteria based on dimensional, structural and fracture requirements, has been established in the form of Engineering specifications and drawings. These criteria originated from actual hardware testing (both subscale and full scale) coupled with conventional Engineering hand calculations and computerized Finite Element Analyses (FEA). The intent of this paper is to provide an overview of the RSRM Case component refurbishment requirements and the associated case hardware inspection and evaluation processes that has been established to satisfy these requirements. Many of these processes have been recently upgraded to comply with environmental regulations, obsolescence concerns and technological advancements. Qualification of these process changes has been closely monitored and documented through test plans and reports.

Brinkerhoff, Gary Z.↗

NASA NTRS1993

Analysis of rocket beacon transmissions for computerized reconstruction of ionospheric densities

Three methods are described to obtain ionospheric electron densities from transionospheric, rocket-beacon TEC data. First, when the line-of-sight from a ground receiver to the rocket beacon is tangent to the flight trajectory, the electron concentration can be obtained by differentiating the TEC with respect to the distance to the rocket. A similar method may be used to obtain the electron-density profile if the layer is horizontally stratified. Second, TEC data obtained during chemical release experiments may be interpreted with the aid of physical models of the disturbed ionosphere to yield spatial maps of the modified regions. Third, computerized tomography (CT) can be used to analyze TEC data obtained along a chain of ground-based receivers aligned along the plane of the rocket trajectory. CT analysis of TEC data is used to reconstruct a 2D image of a simulated equatorial plume. TEC data is computed for a linear chain of nine receivers with adjacent spacings of either 100 or 200 km. The simulation data are analyzed to provide an F region reconstruction on a grid with 15 x 15 km pixels. Ionospheric rocket tomography may also be applied to rocket-assisted measurements of amplitude and phase scintillations and airglow intensities.

Bernhardt, P. A.↗

NASA NTRS1988

Micro-based fact collection tool user's manual

A procedure designed for use by an analyst to assist in the collection and organization of data gathered during the interview processes associated with system analysis and modeling task is described. The basic concept behind the development of this tool is that during the interview process an analyst is presented with assertions of facts by the domain expert. The analyst also makes observations of the domain. These facts need to be collected and preserved in such a way as to allow them to serve as the basis for a number of decision making processes throughout the system development process. This tool can be thought of as a computerization of the analysts's notebook.

Mayer, Richard↗

NASA NTRS1990

Computer-assisted knowledge acquisition for hypermedia systems

The usage of procedural and declarative knowledge to set up the structure or 'web' of a hypermedia environment is described. An automated knowledge acquisition tool was developed that helps a knowledge engineer elicit and represent an expert's knowledge involved in performing procedural tasks. The tool represents both procedural and prerequisite, declarative knowledge that supports each activity performed by the expert. This knowledge is output and subsequently read by a hypertext scripting language to generate the link between blank, but labeled cards. Each step of the expert's activity and each piece of supporting declarative knowledge is set up as an empty node. An instructional developer can then enter detailed instructional material concerning each step and declarative knowledge into these empty nodes. Other research is also described that facilitates the translation of knowledge from one form into a form more readily useable by computerized systems.

Steuck, Kurt↗

NASA NTRS1985

Demonstration of various rotor instabilities (exhibit of Bently Rotor Dynamics Research Corporation Laborator rigs at symposium on instability in rotaing machinery)

The operation of rotor rigs used to demonstrate various instability phenomena occurring in rotating machines is described. The instability phenomena demonstrated included oil whirl/whip antiswirl, rub, loose rotating parts, water-lubricated bearing instabilities, and cracked shaft. The rotor rigs were also used to show corrective measures for preventing instabilities. Vibrational response data from the rigs were taken with modern, computerized instrumentation. The rotor nonsynchronous perturbation rig demonstrated modal identification techniques for rotor/bearing systems. Computer-aided data acquisition and presentation, using the dynamic stiffness method, makes it possible to identify rotor and bearing parameters for low modes. The shaft mode demonstrator presented the amplified modal shape line of the shaft excited by inertia forces of unbalance (synchronous perturbation). The first three bending modes of the shaft can be demonstrated. The user-friendly software, Orbits, presented a simulation of rotor precessional motion that is characteristic of various instability phenomena. The data presentation demonstration used data measured on a turbine driven compressor train as an example of how computer aided data acquisition and presentation assists in identifying rotating machine malfunctions.

Muszynska, A.↗

NASA NTRS1973

A semi-automated system for plotting and computer cataloging of remote sensing imagery

Description of a computer-assisted system for plotting and descriptor-cataloging of aerial imagery - an ingredient of the aerial image data handling system of the NASA Earth Resources Aircraft Project (ERAP). The system under consideration uses two graphic tablets linked interactively with a digital computer as input devices for deriving frame coordinates by correlating image points to map points. The various software programs and operating modes facilitate a semiautomatic plotting of an image by selecting two or more points within the image for matching with map details. The computer performs the scaling and orientation transformations for the calculation of the center and corner coordinates of the frame. Twenty five other descriptors for each frame are fed into a computerized data base requiring a minimum operator's time for verification and correction.

Gnauck, G. E.↗

NASA NTRS1998

Synaptic changes in rat maculae in space and medical imaging: the link

Two different space life sciences missions (SLS-1 and SLS-2) have demonstrated that the synapses of the hair cells of rat vestibular maculae increase significantly in microgravity. The results also indicate that macular synapses are sensitive to stress. These findings argue that vestibular maculae exhibit neuroplasticity to macroenvironmental and microenvironmental changes. This capability should be clinically relevant to rehabilitative training and/or pharmacological treatments for vestibular disease. The results of this ultrastructural research also demonstrated that type I and type II hair cells are integrated into the same neuronal circuitry. The findings were the basis for development of three-dimensional reconstruction software to learn details of macular wiring. This software, produced for scientific research, has now been adapted to reconstruct the face and skull directly from computerized tomography scans. In collaboration with craniofacial reconstructive surgeons at Stanford University Medical Center, an effort is under way to produce a virtual environment workbench for complex craniofacial surgery. When completed, the workbench will help surgeons train for and simulate surgery. The methods are patient specific. This research illustrates the value of basic research in leading to unanticipated medical applications.

Flight Experiment↗

NASA NTRS2001

An integrated software suite for surface-based analyses of cerebral cortex

The authors describe and illustrate an integrated trio of software programs for carrying out surface-based analyses of cerebral cortex. The first component of this trio, SureFit (Surface Reconstruction by Filtering and Intensity Transformations), is used primarily for cortical segmentation, volume visualization, surface generation, and the mapping of functional neuroimaging data onto surfaces. The second component, Caret (Computerized Anatomical Reconstruction and Editing Tool Kit), provides a wide range of surface visualization and analysis options as well as capabilities for surface flattening, surface-based deformation, and other surface manipulations. The third component, SuMS (Surface Management System), is a database and associated user interface for surface-related data. It provides for efficient insertion, searching, and extraction of surface and volume data from the database.

NASA Discipline Neuroscience↗

NASA NTRS2011

Split-screen display system and standardized methods for ultrasound image acquisition and multi-frame data processing

A standardized acquisition methodology assists operators to accurately replicate high resolution B-mode ultrasound images obtained over several spaced-apart examinations utilizing a split-screen display in which the arterial ultrasound image from an earlier examination is displayed on one side of the screen while a real-time "live" ultrasound image from a current examination is displayed next to the earlier image on the opposite side of the screen. By viewing both images, whether simultaneously or alternately, while manually adjusting the ultrasound transducer, an operator is able to bring into view the real-time image that best matches a selected image from the earlier ultrasound examination. Utilizing this methodology, dynamic material properties of arterial structures, such as IMT and diameter, are measured in a standard region over successive image frames. Each frame of the sequence has its echo edge boundaries automatically determined by using the immediately prior frame's true echo edge coordinates as initial boundary conditions. Computerized echo edge recognition and tracking over multiple successive image frames enhances measurement of arterial diameter and IMT and allows for improved vascular dimension measurements, including vascular stiffness and IMT determinations.

Selzer, Robert H.↗

DOE OSTI2020

Design and Development of a Robotic Exoskeleton Device for use in Glove Boxes - 20374

Glovebox operators in nuclear facilities often operate under radioactive environment and typically perform monotonous, dull and repetitive work. This can result in muscle fatigue leading to increased levels of accidents. Current research work aims in assisting the glovebox operators by designing a novel upper limb exoskeleton device to reduce injuries and increase worker efficiency. Almost none of the commercially available hand and upper body exoskeletons are directly suitable for use in gloveboxes. This explains the novelty of the present work in developing a wearable powered robotic exoskeleton device. The device consists of electronics, motors and spring systems mounted on adjustable plates and is supported by a stationary frame behind the worker. The device is intended to be portable and adjustable according to the operator height. The elbow has a flexion movement assisted with motor control by way of a Bowden cable system. The system is floated on a spring and pulley combination that allows for extra safety and smoothness of operation. The end points are fixed near the pivot points to help minimize unwanted movement/torque. The extension movement of the upper and lower arm are assisted by gravity and a counter spring. The shoulder and upper arm movement are held in a neutral position with a spring system for counter balance allowing small movements within the glovebox. This initial concept considers only the vertical movement of the arm. The abduction and adduction movement will not be assisted or impeded by the over shoulder plate or at the forearm plate allowing for full range of motion. Several glovebox aspects such as the level of task assistance, ergonomic design, minimum hindrance in dexterity/operator movements and tear resistance for hazardous safety reasons will be considered in the design of the exoskeleton. Computer models will be simulated to test the load levels and stress conditions on the exoskeleton to enhance the designs. The exoskeleton focusses on major muscular involvement reduction through weight offset and active assistance with minimal parts and hence the device is derived with several joint links and contains both passive and active joints. The paper details the various stages in the design development and prototype testing of the exoskeleton device. Upon successful prototype device development, human testing will be conducted in a replica of the SRS-235F hot cell facility constructed at FIU-ARC. The final stage of the project will be potential testing/deployment of the exoskeleton device in one of the glovebox facilities in Savannah River Nuclear Waste site. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2020

Ion-Exchange Modeling of Crystalline Silicotitanate for Cesium Removal - 20283

The Tank Closure Cesium Removal (TCCR) system is a Savannah River Site (SRS) demonstration 'at-tank' process designed to remove {sup 137}Cs from the high-level aqueous tank waste so that the decontaminated solution can be disposed as low-level waste. Cesium is removed by ion exchange (IX) columns using engineered IONSIV{sup TM} R9120-B form of the Crystalline Silicotitanate (CST) media. The TCCR system is deployed at Tanks 10 and Tank 11 in the SRS H Tank Farm. Water is added to the salt-cake in Tank 10 H to dissolve it. The dissolved salt solution waste is pumped out of Tank 10H (feed tank), through filters and IX columns. The decontaminated salt solution is transferred to Tank 11 (receipt tank), and on to Tank 50H for final disposal in the Saltstone Production Facility. The current TCCR can accommodate lead-lag (two-column) or lead-lag-guard (three-column) configurations to optimize media utilization and achieve the target decontamination. To assist the TCCR operations, a parametric study was conducted to evaluate the impact of different parameters (e.g., column configurations (single column, two columns or three columns in series), waste characteristics, operating temperature, process flow rate, CST average particle size) on the IX column performance including CST bed utilization. The initial results indicate that the IX column performance is improved at slower process flow rate, at lower operating temperature, and with smaller CST average particle size. Multi-column configurations are recommended, because the single-column configuration does not utilize CST bed effectively. This paper demonstrates the versatility of the ion exchange modeling to evaluate the effects of CST characteristics and operational parameters on IX column performances. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

NASA NTRS1997

Functional specializations in human cerebral cortex analyzed using the Visible Man surface-based atlas

We used surface-based representations to analyze functional specializations in the human cerebral cortex. A computerized reconstruction of the cortical surface of the Visible Man digital atlas was generated and transformed to the Talairach coordinate system. This surface was also flattened and used to establish a surface-based coordinate system that respects the topology of the cortical sheet. The linkage between two-dimensional and three-dimensional representations allows the locations of published neuroimaging activation foci to be stereotaxically projected onto the Visible Man cortical flat map. An analysis of two activation studies related to the hearing and reading of music and of words illustrates how this approach permits the systematic estimation of the degree of functional segregation and of potential functional overlap for different aspects of sensory processing.

Non-NASA Center↗

NASA NTRS2001

Root elongation against a constant force: experiment with a computerized feedback-controlled device

Axial force was applied to the root tip of corn (Zea mays L. cv. Merit) seedlings using a computerized, feedback-controlled mechanical device. The system's feedback capability allowed continuous control of a constant tip load, and the attached displacement transducer provided the time course of root elongation. Loads up to 7.5 g decreased the root elongation rate by 0.13 mm h-1 g-1, but loads 7.5 to 17.5 g decreased the growth rate by only 0.04 mm h-1 g-1. Loads higher than 18 g stopped root elongation completely. Measurement of the cross-sectional areas of the root tips indicated that the 18 g load had applied about 0.98 MPa of axial pressure to the root, thereby exceeding the root's ability to respond with increased turgor pressure. Recorded time-lapse images of loaded roots showed that radial thickening (swelling) occurred behind the root cap, whose cross-sectional area increased with tip load.

Non-NASA Center↗

NASA NTRS1998

Comparison of MPEG digital video with super VHS tape for diagnostic echocardiographic readings

BACKGROUND: Digital recording of echocardiographic studies is on the clinical horizon. However, full digital capture of complete echocardiographic studies in traditional video format is impractical, given current storage capacity and network bandwidth. To overcome these constraints, we evaluated the diagnostic image quality of digital video by using MPEG (Motion Picture Experts Group) compression. METHODS AND RESULTS: Fifty-eight complete, consecutive studies were recorded simultaneously with the use of MPEG-1 and sVHS videotape. Each matched MPEG and sVHS study pair was reviewed by two from a total of six readers, and findings were recorded with the use of a detailed, computerized reporting tool. Intrareader and interreader discrepancies were characterized as major or minor and analyzed in total and for specific subgroups of findings (left and right ventricular parameters, valvular insufficiency, and left ventricular regional wall motion). Intrareader discrepancies were reviewed by a consensus panel for agreement with either MPEG or sVHS findings. There was an exact concordance between MPEG and sVHS readings in 83% of findings. The majority of discrepancies were minor, with major discrepancies in only 2.7% of findings. There was no difference in the rate of consensus panel agreement with MPEG or sVHS for instances of intrareader discrepancy, either in total or for any subgroup of findings. Interreader discrepancy rates were nearly identical for both MPEG and sVHS. CONCLUSIONS: MPEG-1 digital video is equivalent to sVHS videotape for diagnostic echocardiography. MPEG increases the range of practical options for digital echocardiography and offers, for the first time, the advantages of digital recording in a familiar video format.

Non-NASA Center↗

NASA NTRS1996

Computerized mappings of the cerebral cortex: a multiresolution flattening method and a surface-based coordinate system

We present a new method for generating two-dimensional maps of the cerebral cortex. Our computerized, two-stage flattening method takes as its input any well-defined representation of a surface within the three-dimensional cortex. The first stage rapidly converts this surface to a topologically correct two-dimensional map, without regard for the amount of distortion introduced. The second stage reduces distortions using a multiresolution strategy that makes gross shape changes on a coarsely sampled map and further shape refinements on progressively finer resolution maps. We demonstrate the utility of this approach by creating flat maps of the entire cerebral cortex in the macaque monkey and by displaying various types of experimental data on such maps. We also introduce a surface-based coordinate system that has advantages over conventional stereotaxic coordinates and is relevant to studies of cortical organization in humans as well as non-human primates. Together, these methods provide an improved basis for quantitative studies of individual variability in cortical organization.

Non-NASA Center↗