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NASA NTRS2019

Development of a Point of Care Technology for Military Medical Applications in Austere Environments

NASA, Lawrence Livermore National Laboratory (LLNL) and the Department of Defense (DoD) share a common interest in compact medical diagnostic technologies—also known as “point of care testing” (POCT) technologies. For NASA, the need is to take care of astronauts on deep space missions. For LLNL, the focus is on technologies needed to support homeland security applications. For DoD, the need is to support warfighters in military theaters of operation, especially for prolonged field care and en route care. A recently patented technology, “Portable Medical Diagnosis Instrument” (U.S. Patent 9824870), co-invented by NASA and LLNL, is being developed further in a partnership between NASA, LLNL and Travis Air Force Base, with a focus on military applications. This instrument, the NASA-LLNL Medical Tricorder, can be used for a wide range of clinical samples including breath, saliva and blood. One component of the Tricorder is the NASA E-Nose, a carbon nanotube-based chemical sensor, integrated into a hand-held smart phone, that can detect and measure “breath biomarkers” in the gas phase of exhaled breath. The response of the NASA E-Nose is rapid, which makes it possible to detect various gas-phase substances in real time. The NASA E-Nose, with modification, can also be used for breath condensate analysis. Another component of the Tricorder is a miniaturized microfluidic analyzer, under development by LLNL, that does not require any pumps. The microfluidic analyzer can detect and measure biomarkers in liquid samples, such as blood, saliva and breath condensate. This microfluidic system requires small quantities of liquid sample and can perform analysis very rapidly (seconds to minutes), which makes it possible to detect relevant biomarkers in near real time in the field. The Clinical Investigation Facility (CIF) at Travis Air Force Base is currently conducting research with the goal to develop improved field-able technologies and procedures for the emergency response to life threatening injuries soldiers may receive in theater. This work includes experimental large animal systems and comprehensive collection of clinical specimens and physiological data. NASA and LLNL are partnering with Travis to test and further develop the Tricorder technology for high priority military applications, initially focused on lung injury models and traumatic brain injury.

Loftus, David J.↗

NASA NTRS1993

Welding process modelling and control

The research and analysis performed, and software developed, and hardware/software recommendations made during 1992 in development of the PC-based data acquisition system for support of Welding Process Modeling and Control is reported. A need was identified by the Metals Processing Branch of NASA Marshall Space Flight Center, for a mobile data aquisition and analysis system, customized for welding measurement and calibration. Several hardware configurations were evaluated and a PC-based system was chosen. The Welding Measurement System (WMS) is a dedicated instrument, strictly for the use of data aquisition and analysis. Although the WMS supports many of the functions associated with the process control, it is not the intention for this system to be used for welding process control.

Romine, Peter L.↗

NASA NTRSDate not supplied

Mars Commercial-Compatible Initial Human-Precursor Surveying and Instrument-Deployment Concepts

Water is a critical resource need for future human exploration and habitation of Mars and other planetary environments. An integral scientific question in the search for life outside of Earth is: What are the constraints on life in planetary environments? One of the most critical features of habitable environments is the availability of water - both as an environment for prebiotic chemistry, abiogenesis, and life; and as a vehicle for generating geo- and electro- chemical systems that can support metabolism. Seeking evidence of life prior to human arrival is important both to preserve signs of any existing or past evidence of Martian life, reducing the risks of unintentional forward contamination of Martian environments, and to potentially protect the health of any human crews. Looking forward towards Mars, future human exploration will require a rapid, but thorough, initial survey of any local “area of operations” on Mars to determine the spatial distribution, quantity, and quality (e.g., salt/mineral/organic content) of any local water, as well as to evaluate any signs of current or extinct life. We will discuss several candidate field survey methodologies, involving humans, a teamed instrument platform and a surveying/sampling rover. These are proposed to be validated in a given terrestrial Mars analog environment exhibiting varying distributions of water (ice, permafrost, rock-bound) to evaluate the constraints on life. Commercial space exploration brings the future possibility of unprecedented mass, power and in situ instrument capability, potentially enabling thorough exploration of the geology, hydrology and astrobiology of a km-radius study-zone around a future Mars human/commercial space landing site. We propose to study several representative planetary surface precursor-survey architectures and mission concepts (that are commercial-Mars-compatible), and to test and compare them in field application. We will examine some of the performance issues, using given metrics and controls, of spacesuited humans using handheld and standalone instruments, vs. a robotic human-tended rover/drill, robot arm and instruments. The latter rover-based architecture can in turn be viewed in terms of returned-to-base sample in-situ analyses vs sample analysis performed on a standalone instrument platform deployed away from the primary area of operations.

astrobiology↗

NASA NTRS1987

Quantitative analysis of the reconstruction performance of interpolants

The analysis presented provides a quantitative measure of the reconstruction or interpolation performance of linear, shift-invariant interpolants. The performance criterion is the mean square error of the difference between the sampled and reconstructed functions. The analysis is applicable to reconstruction algorithms used in image processing and to many types of splines used in numerical analysis and computer graphics. When formulated in the frequency domain, the mean square error clearly separates the contribution of the interpolation method from the contribution of the sampled data. The equations provide a rational basis for selecting an optimal interpolant; that is, one which minimizes the mean square error. The analysis has been applied to a selection of frequently used data splines and reconstruction algorithms: parametric cubic and quintic Hermite splines, exponential and nu splines (including the special case of the cubic spline), parametric cubic convolution, Keys' fourth-order cubic, and a cubic with a discontinuous first derivative. The emphasis in this paper is on the image-dependent case in which no a priori knowledge of the frequency spectrum of the sampled function is assumed.

Lansing, Donald L.↗

NASA NTRS1992

Verification of rain-flow reconstructions of a variable amplitude load history

The suitability of using rain-flow reconstructions as an alternative to an original loading spectrum for component fatigue life testing is investigated. A modified helicopter maneuver history is used for the rain-flow cycle counting and history regenerations. Experimental testing on a notched test specimen over a wide range of loads produces similar lives for the original history and the reconstructions. The test lives also agree with a simplified local strain analysis performed on the specimen utilizing the rain-flow cycle count. The rain-flow reconstruction technique is shown to be a viable test spectrum alternative to storing the complete original load history, especially in saving computer storage space and processing time. A description of the regeneration method, the simplified life prediction analysis, and the experimental methods are included in the investigation.

Clothiaux, John D.↗

NASA NTRS1977

Shuttle/GPSPAC experimentation study

The utilization is discussed of the GPSPAC, which is presently being developed to be used on the low altitude host vehicle (LAHV), for possible use in the shuttle avionics system to evaluate shuttle/GPS navigation performance. Analysis and tradeoffs of the shuttle/GPS link, shuttle signal interface requirements, oscillator tradeoffs and GPSPAC mechanical modifications for shuttle are included. Only the on-orbit utilization of GPSPAC for the shuttle is discussed. Other phases are briefly touched upon. Recommendations are provided for using the present GPSPAC and the changes required to perform shuttle on-orbit navigation.

Moses, J.↗

NASA NTRS1988

In situ XRF and gamma ray spectrometer for Mars sample return mission

A combined in situ X-ray fluorescence (XRF) and passive gamma ray spectrometer instrument is proposed for the chemical elemental analysis of various Martian surfaces and samples. The combined instrument can be carried on board a rover. The passive gamma ray or the neutron excited gamma ray system would be used to determine the elemental composition of the Martian surface while the rover is in motion. The XRF system would be used to perform analysis either on the Martian surface or on collected samples when the rover is stationary. The latter function is important both in cataloging the collected samples and in the selection of samples to be returned to earth. For both systems, data accumulation time would be on the order of 30 minutes. No sample preparation would be necessary.

Lo, I. Yin↗

NASA NTRS2010

Analysis of Anechoic Chamber Testing of the Hurricane Imaging Radiometer

The Hurricane Imaging Radiometer System (HIRAD) is a new airborne passive microwave remote sensor developed to observe hurricanes. HIRAD incorporates synthetic thinned array radiometry technology, which use Fourier synthesis to reconstruct images from an array of correlated antenna elements. The HIRAD system response to a point emitter has been measured in an anechoic chamber. With this data, a Fourier inversion image reconstruction algorithm has been developed. Performance analysis of the apparatus is presented, along with an overview of the image reconstruction algorithm

Fenigstein, David↗

DOE OSTI2024

PaRSEC: Scalability, flexibility, and hybrid architecture support for task-based applications in ECP

This paper highlights the most significant enhancements made to PaRSEC, a scalable task-based runtime system designed for hybrid machines, during the Exascale Computing Project (ECP). The enhancements focus on expanding the capabilities of PaRSEC to address the evolving landscape of parallel computing. Notable achievements include the integration of support for three major types of accelerators (NVIDIA, AMD, and Intel GPUs), the refinement and increased flexibility of the communication subsystem, and the introduction of new programming interfaces tailored for irregular applications. Additionally, the project resulted in the development of powerful debugging and performance analysis tools aimed at assisting users in understanding and optimizing their applications. We present a comprehensive demonstration of these advancements through a series of benchmarks and applications within ECP and beyond, thereby showcasing the enhanced capabilities of PaRSEC across the diverse architectures within the ECP, providing valuable insights into the runtime system’s adaptability and performance across varied computing environments.

Bouteiller, Aurelien↗

NASA NTRS1984

Review of SERI Solar Pond Work

Development of models of pond thermal performance; analysis of solar pond use for building space heat and hot water production; use of low-temperature pond-produced heat for industrial processes, desalination, and electricity production; development of direct-contact heat exchanger to reduce conversion equipment cost; determination of effects of extracted heat and mass from the storage layer on pond performance; and investigation of factors which determine gradient layer stability and the stability of this interface between this level and the upper and lower convecting layers were described.

Zangrando, F.↗

NASA NTRS1986

Controlled Ecological Life Support Systems (CELSS) conceptual design option study

Results are given of a study to explore options for the development of a Controlled Ecological Life Support System (CELSS) for a future Space Station. In addition, study results will benefit the design of other facilities such as the Life Sciences Research Facility, a ground-based CELSS demonstrator, and will be useful in planning longer range missions such as a lunar base or manned Mars mission. The objectives were to develop weight and cost estimates for one CELSS module selected from a set of preliminary plant growth unit (PGU) design options. Eleven Space Station CELSS module conceptual PGU designs were reviewed, components and subsystems identified and a sensitivity analysis performed. Areas where insufficient data is available were identified and divided into the categories of biological research, engineering research, and technology development. Topics which receive significant attention are lighting systems for the PGU, the use of automation within the CELSS system, and electric power requirements. Other areas examined include plant harvesting and processing, crop mix analysis, air circulation and atmosphere contaminant flow subsystems, thermal control considerations, utility routing including accessibility and maintenance, and nutrient subsystem design.

Oleson, Melvin↗

DOE OSTI2024

Accuracy of kinetic equilibrium reconstruction of NSTX and NSTX-U plasmas and its impact on the transport and stability analysis

An accurate magnetohydrodynamic (MHD) equilibrium reconstruction is an essential starting point for stability and transport plasma analysis. Herein this work describes an approach for obtaining kinetic equilibrium reconstructions using the OMFIT framework, which has been applied for the first time to spherical tokamak data from NSTX and NSTX-U. The EFIT equilibrium solver is integrated with experimental data analysis procedures and subsequent TRANSP transport simulations to enhance the accuracy of the reconstruction, in particular, at the edge region, by adding constraints on the total pressure and current density profiles, based on the transport code solution. The accuracy of the equilibrium reconstruction depends on the uncertainty and number of constraints, as well as the choice of basis functions to represent the pressure and current density profiles. Improved fidelity of the equilibrium reconstruction is demonstrated by reducing the variability of the magnetic axis and boundary locations from several centimeters, for reconstructions based on magnetic and experimental pressure constraints, to only several millimeters, for kinetic reconstructions based on transport code constraints, when different representations of basis functions were tested. The variability of the safety factor on axis was reduced ten times in the same sensitivity study. The accuracy of the equilibrium reconstruction and subsequent mapping of the experimental kinetic profile data have a significant impact on the trapped gyro Landau fluid and linear CGYRO turbulence simulations, which predict different spectra of unstable modes and turbulent fluxes for cases with different numbers of constraints in the equilibrium reconstruction. Conversely, the stability analysis performed using the GATO code shows plasmas that are stable to n = 1 MHD modes in both equilibria using magnetic and experimental pressure constraints as well as the transport code constrained equilibrium. However, a scan of parameters away from these conditions shows considerable deviation in the threshold of unstable modes between these reconstructions. Therefore, for reliable plasma analysis and use in turbulence and stability calculations, a high-fidelity equilibrium reconstruction with accurate kinetic constraints based on transport code solutions is necessary.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

NASA NTRS1975

Precise optical pulse timing

This paper evaluates the performance of the maximum likelihood and several sub-optimum arrival time estimators for optical pulses. The performance analysis of a 'sliding window' counter followed by that of a threshold detector is achieved by deriving an expression for the first crossing density of the output of the counter. A sub-optimum arrival time estimator using a threshold rather than a maximum detector is suggested and evaluated by simulation. It appears to provide near optimum performance.

Lee, G.↗

NASA NTRS1991

FAST: A multi-processed environment for visualization of computational fluid

Three dimensional, unsteady, multizoned fluid dynamics simulations over full scale aircraft is typical of problems being computed at NASA-Ames on CRAY2 and CRAY-YMP supercomputers. With multiple processor workstations available in the 10 to 30 Mflop range, it is felt that these new developments in scientific computing warrant a new approach to the design and implementation of analysis tools. These large, more complex problems create a need for new visualization techniques not possible with the existing software or systems available as of this time. These visualization techniques will change as the supercomputing environment, and hence the scientific methods used, evolve ever further. Visualization of computational aerodynamics require flexible, extensible, and adaptable software tools for performing analysis tasks. FAST (Flow Analysis Software Toolkit), an implementation of a software system for fluid mechanics analysis that is based on this approach is discussed.

Bancroft, Gordon V.↗

NASA NTRS2004

Space Shuttle Upgrades: Long Life Alkaline Fuel Cell

NASA has utilized the alkaline fuel cell technology to provide electrical power for manned launch vehicles such as Gemini, Apollo, and the Space Shuttle. The current Shuttle alkaline fuel cells are procured from UTC Fuel Cells, a United Technologies Company. The alkaline fuel cells are very reliable but the operating life is limited to 2600 hours due to voltage degradation of the individual cells. The main limiting factor in the life of the cells is corrosion of the cell's fiberglass/epoxy frame by the aqueous potassium hydroxide electrolyte. To reduce operating costs, the orbiter program office approved the Long Life Alkaline Fuel Cell (LLAFC) program as a shuttle upgrade in 1999 to increase the operating life of the fuel cell powerplant to 5000 hours. The LLAFC program incorporates improving the cell by extending the length of the corrosion path, which reduces the cell frame corrosion. UTCFC performed analysis to understand the fundamental mechanisms that drive the cell frame corrosion. The analysis indicated that the corrosion path started along the bond line between the cathode and the cell frame. Analysis also showed that the oxygen available at the cathode, the catalyst on the electrode, and the electrode substrate all supported or intensified the corrosion. The new cell design essentially doubled the corrosion path to mitigate the problem. A 10-cell stack was tested for 5000 hours during the development phase of this program to verify improved cell performance. A complete 96-cell stack was then tested for 5000 hours during the full manned-space qualification phase of this program. Additional upgrades to the powerplant under this program are: replacing the aluminum body in the pressure regulator with stainless steel to reduce corrosion, improving stack insulator plate with improved resistance to stress failure and improved temperature capability, and replacing separator plate elastomer seals with a more durable material and improved seal retention.

Kerri McCurdy↗

DOE OSTI2020

As-Run Neutronics Evaluation for the CSM-10584 Experiment in the ATR

This engineering calculations and analysis report (ECAR) documents the results of the Advanced Test Reactor (ATR) detailed Monte Carlo N-Particle (MCNP) code full-core model as-run physics analysis performed to support the Colorado School of Mines (CSM) experiment in the B-5 position.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗

NASA NTRS1986

Energy Efficient Engine: Combustor component performance program

The results of the Combustor Component Performance analysis as developed under the Energy Efficient Engine (EEE) program are presented. This study was conducted to demonstrate the aerothermal and environmental goals established for the EEE program and to identify areas where refinements might be made to meet future combustor requirements. In this study, a full annular combustor test rig was used to establish emission levels and combustor performance for comparison with those indicated by the supporting technology program. In addition, a combustor sector test rig was employed to examine differences in emissions and liner temperatures obtained during the full annular performance and supporting technology tests.

Dubiel, D. J.↗

NASA NTRS1991

The ONR-602 experiment and investigation of particle precipitation near the equator

The global precipitation of radiation belt particles at low altitude was investigated, using the ONR-602 experiment on board U.S. Air Force mission S81-1. A combination of a main telescope, beginning analysis at a few MeV/nucleon, and a monitor system, giving results below 1 MeV/nucleon, was designed for measuring particle phenomena characterized by almost any energy spectrum. The monitor provides an indication of the presence of the particles at low energy, while the main telescope gives detailed flux and composition data for the higher energy events. Results of the instrument performance analysis indicate that, at the equator, the monitor telescope has the peak efficiency for particles of about 90 deg pitch angles. The large opening angle of 75 deg makes it possible to detect omnidirectional flux of quasi-trapped particles. The high-energy cosmic-ray background count is found to be very insignificant. It is demonstrated that the particle counting rates for the low-energy threshold have been almost entirely due to protons.

Miah, M. A.↗