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All sourcesNASA NTRSDOE OSTI
NASA NTRS1996

Extending the JOVE Program through undergraduate research

The JOVE program was initiated in 1988 to develop NASA-related research capabilities in colleges and universities which had had little or no previous experience with NASA. Any institution which was not currently funded at more than $100 K annually by NASA was eligible. In an open competition six universities were selected for participation in the first year. NASA supplied funds, access to its facilities and data, collaboration with its researchers and a hookup to the internet. In return the university was expected to match NASA's investment by giving its participating faculty members time off of their teaching schedules to perform research during the school year, by waiving it overhead charge and by putting up real funds to match those supplied by NASA. Each school was eligible for three years after which they were expected to seek funds from other sources. Over the span of the program more than 100 colleges and universities have participated. Fifteen have finished their eligiblity. Since one of the strong components of the program was the direct involvement of undergraduate students in active research, it was decided to develop a follow-on program which would provide stipends to undergraduate students at the institutions who had used up their JOVE eligiblity. NASA's desire to transfer its technologies to the private sector now permeates all of its programs. Therefore a Partnering Venture (PAVE) program is now being discussed in which JOVE-like rules will be applied to small companies which do not now do much business with NASA. The JOVE, PAVE, and other summer activities of the author are told here.

Lebo, George R.↗
NASA NTRS1995

Space Life-Support Engineering Program

This report covers the seventeen months of work performed under an extended one year NASA University Grant awarded to Iowa State University to perform research on topics relating to the development of closed-loop long-term life support systems with the initial principal focus on space water management. In the first phase of the program, investigators from chemistry and chemical engineering with demonstrated expertise in systems analysis, thermodynamics, analytical chemistry and instrumentation, performed research and development in two major related areas; the development of low-cost, accurate, and durable sensors for trace chemical and biological species, and the development of unsteady-state simulation packages for use in the development and optimization of control systems for life support systems. In the second year of the program, emphasis was redirected towards concentrating on the development of dynamic simulation techniques and software and on performing a thermodynamic systems analysis, centered on availability or energy analysis, in an effort to begin optimizing the systems needed for water purification. The third year of the program, the subject of this report, was devoted to the analysis of the water balance for the interaction between humans and the life support system during space flight and exercise, to analysis of the cardiopulmonary systems of humans during space flight, and to analysis of entropy production during operation of the air recovery system during space flight.

Seagrave, Richard C.↗
NASA NTRS1996

Advanced Configurations for Very Large Subsonic Transport Airplanes

Recent aerospace industry interest in developing a subsonic commercial transport airplane with 50 percent greater passenger capacity than the largest existing aircraft in this category (the Boeing 747-400 with approximately 400-450 seats) has generated a range of proposals based largely on the configuration paradigm established nearly 50 years ago with the Boeing B-47 bomber. While this basic configuration paradigm has come to dominate subsonic commercial airplane development since the advent of the Boeing 707/Douglas DC-8 in the mid-1950's, its extrapolation to the size required to carry more than 600-700 passengers raises several questions. To explore these and a number of related issues, a team of Boeing, university, and NASA engineers was formed under the auspices of the NASA Advanced Concepts Program. The results of a Research Analysis focused on a large, unconventional transport airplane configuration for which Boeing has applied for a patent are the subject of this report. It should be noted here that this study has been conducted independently of the Boeing New Large Airplane (NLA) program, and with the exception of some generic analysis tools which may be common to this effort and the NLA (as will be described later), no explicit Boeing NLA data other than that published in the open literature has been used in the conduct of the study reported here.

McMasters, John H.↗
NASA NTRS1998

Catastrophic Collapse of Particulate Clouds: Implications From Aggregation Experiments in the USML-1 and USML-2 Glovebox

Experiments with electrostatic aggregation of well-dispersed (nominally, mono-dispersed), freely suspended particles in the United States Microgravity Laboratory (USML) Glovebox have determined that filamentary aggregates are a universal product of grain interactions in relatively dense particulate clouds. Aggregate growth from the experimental particle clouds primarily involves dipole-dipole interactions for nonconducting materials; dipole interactions account for both attraction between grains as well as the cohesive force that maintains the integrity of the filamentary structures. When a cloud undergoes a turbulent-to-quiescent transition after damping of fluid and ballistic grain motions, aggregation occurs almost instantaneously and the cloud is transformed into a population of "heavier" clusters of material with organized electrical structures. This abrupt transformation could initiate catastrophic gravitational collapse of certain regions of particulate clouds, thus controlling the longevity and fate of cloud systems as diverse as protoplanetary dust disks and volcanic eruption plumes.

Marshall, John↗
NASA NTRS2000

Simulation of a Flywheel Electrical System for Aerospace Applications

A Flywheel Energy Storage Demonstration Project was initiated at the NASA Glenn Research Center as a possible replacement for the battery energy storage system on the International Space Station (ISS). While the hardware fabrication work was being performed at a university and contractor's facility, the related simulation activity was begun at Glenn. At the top level, Glenn researchers simulated the operation of the ISS primary electrical system (as described in another paper) with the Flywheel Energy Storage Unit (FESU) replacing one Battery Charge and Discharge Unit (BCDU). The FESU consists of a Permanent Magnet Synchronous Motor/Generator (PMSM), which is connected to the flywheel; the power electronics that connects the PMSM to the ISS direct-current bus; and the associated controller. The PMSM model is still under development, but this paper describes the rest of the FESU model-the simulation of the converter and the associated control system that regulates energy transfer to and from the flywheel.

Truong, Long V.↗
NASA NTRS2004

Application of Remote Sensing to Assess the Impact of Short Term Climate Variability on Coastal Sedimentation

The purpose of this joint University of Wisconsin (UW) and Louisiana State University (LSU) project has been to relate short term climate variation to response in the coastal zone of Louisiana in an attempt to better understand how the coastal zone is shaped by climate variation. Climate variation in this case largely refers to variation in surface wind conditions that affect wave action and water currents in the coastal zone. The primary region of focus was the Atchafalaya Bay and surrounding bays in the central coastal region of Louisiana. Suspended solids in the water column show response to wind systems both in quantity (through resuspension) and in the pattern of dispersement or transport. Wind systems associated with cold fronts are influenced by short term climate variation. Wind energy was used as the primary signature of climate variation in this study because winds are a significant influence on sediment transport in the micro-tidal Gilf of Mexico coastal zone. Using case studies, the project has been able to investigate the influence of short term climate variation on sediment transport. Wind energy data, collected daily for National Weather Service (NWS) stations at Lake Charles and New Orleans, LA, were used as an indicator of short term climate variation influence on seasonal time scales. A goal was to relate wind energy to coastal impact through sediment transport. This goal was partially accomplished by combining remote sensing and wind energy data. Daily high resolution remote sensing observations are needed to monitor the complex coastal zone environment, where winds, tides, and water level all interact to influence sediment transport. The NASA Earth Observing System (EOS) era brings hope for documenting and revealing response of the complex coastal transport mosaic through regular high spatial resolution observations from the Moderate resolution Imaging Spectrometer (MODIS) instrument. MODIS observations were sampled in this project for information content and should continue to be viewed as a resource for coastal zone monitoring. The project initialized the effort to transfer a suspended sediment concentration (SSC) algorithm to the MODIS platform for case 2 waters. MODIS enables monitoring of turbid coastal zones around the globe. The MODIS SSC algorithm requires refinements in the atmospheric aerosol contribution, sun glint influence, and designation of the sediment inherent optical properties (IOPs); the framework for continued development is in place with a plan to release the algorithm to the MODIS direct broadcast community.

Menzel, W. Paul↗
NASA NTRS2005

Soot Formation in Purely-Curved Premixed Flames and Laminar Flame Speeds of Soot-Forming Flames

The research addressed here is a collaborative project between University of Delaware and Case Western Reserve University. There are two basic and related scientific objectives. First, we wish to demonstrate the suitability of spherical/cylindrical, laminar, premixed flames in the fundamental study of the chemical and physical processes of soot formation. Our reasoning is that the flame standoff distance in spherical/cylindrical flames under microgravity can be substantially larger than that in a flat burner-stabilized flame. Therefore the spherical/cylindrical flame is expected to give better spatial resolution to probe the soot inception and growth chemistry than flat flames. Second, we wish to examine the feasibility of determining the laminar flame speed of soot forming flames. Our basic assumption is that under the adiabatic condition (in the absence of conductive heat loss), the amount and dynamics of soot formed in the flame is unique for a given fuel/air mixture. The laminar flame speed can be rigorously defined as long as the radiative heat loss can be determined. This laminar flame speed characterizes the flame soot formation and dynamics in addition to the heat release rate. The research involves two integral parts: experiments of spherical and cylindrical sooting flames in microgravity (CWRU), and the computational counterpart (UD) that aims to simulate sooting laminar flames, and the sooting limits of near adiabatic flames. The computations work is described in this report, followed by a summary of the accomplishments achieved to date. Details of the microgra+ experiments will be discussed in a separate, final report prepared by the co-PI, Professor C-J. Sung of CWRU. Here only a brief discussion of these experiments will be given.

Buchanan, Thomas↗
NASA NTRS2007

Proceedings of the 20th International Symposium on Space Flight Dynamics

Topics include: Measuring Image Navigation and Registration Performance at the 3-Sigma Level Using Platinum Quality Landmarks; Flight Dynamics Performances of the MetOp A Satellite during the First Months of Operations; Visual Navigation - SARE Mission; Determining a Method of Enabling and Disabling the Integral Torque in the SDO Science and Inertial Mode Controllers; Guaranteeing Pointing Performance of the SDO Sun-Pointing Controllers in Light of Nonlinear Effects; SDO Delta H Mode Design and Analysis; Observing Mode Attitude Controller for the Lunar Reconnaissance Orbiter; Broken-Plane Maneuver Applications for Earth to Mars Trajectories; ExoMars Mission Analysis and Design - Launch, Cruise and Arrival Analyses; Mars Reconnaissance Orbiter Aerobraking Daily Operations and Collision Avoidance; Mars Reconnaissance Orbiter Interplanetary Cruise Navigation; Motion Parameters Determination of the SC and Phobos in the Project Phobos-Grunt; GRAS NRT Precise Orbit Determination: Operational Experience; Orbit Determination of LEO Satellites for a Single Pass through a Radar: Comparison of Methods; Orbit Determination System for Low Earth Orbit Satellites; Precise Orbit Determination for ALOS; Anti-Collision Function Design and Performances of the CNES Formation Flying Experiment on the PRISMA Mission; CNES Approaching Guidance Experiment within FFIORD; Maneuver Recovery Analysis for the Magnetospheric Multiscale Mission; SIMBOL-X: A Formation Flying Mission on HEO for Exploring the Universe; Spaceborne Autonomous and Ground Based Relative Orbit Control for the TerraSAR-X/TanDEM-X Formation; First In-Orbit Experience of TerraSAR-X Flight Dynamics Operations; Automated Target Planning for FUSE Using the SOVA Algorithm; Space Technology 5 Post-Launch Ground Attitude Estimation Experience; Standardizing Navigation Data: A Status Update; and A Study into the Method of Precise Orbit Determination of a HEO Orbiter by GPS and Accelerometer.

Woodard, Mark↗
NASA NTRS2011

Defining Tolerance: Impacts of Delay and Disruption when Managing Challenged Networks

Challenged networks exhibit irregularities in their communication performance stemming from node mobility, power constraints, and impacts from the operating environment. These irregularities manifest as high signal propagation delay and frequent link disruption. Understanding those limits of link disruption and propagation delay beyond which core networking features fail is an ongoing area of research. Various wireless networking communities propose tools and techniques that address these phenomena. Emerging standardization activities within the Internet Research Task Force (IRTF) and the Consultative Committee for Space Data Systems (CCSDS) look to build upon both this experience and scalability analysis. Successful research in this area is predicated upon identifying enablers for common communication functions (notably node discovery, duplex communication, state caching, and link negotiation) and how increased disruptions and delays affect their feasibility within the network. Networks that make fewer assumptions relating to these enablers provide more universal service. Specifically, reliance on node discovery and link negotiation results in network-specific operational concepts rather than scalable technical solutions. Fundamental to this debate are the definitions, assumptions, operational concepts, and anticipated scaling of these networks. This paper presents the commonalities and differences between delay and disruption tolerance, including support protocols and critical enablers. We present where and how these tolerances differ. We propose a set of use cases that must be accommodated by any standardized delay-tolerant network and discuss the implication of these on existing tool development.

mobility drivers↗
NASA NTRS2011

Low-Frequency Gravitational-Wave Science with eLISA/ NGO

We review the expected science performance of the New Gravitational-Wave Observatory (NGO, a.k.a. eLISA), a mission under study by the European Space Agency for launch in the early 2020s. eLISA will survey the low-frequency gravitational-wave sky (from 0.1 mHz to 1 Hz), detecting and characterizing a broad variety of systems and events throughout the Universe, including the coalescences of massive black holes brought together by galaxy mergers; the inspirals of stellar-mass black holes and compact stars into central galactic black holes; several millions of ultracompact binaries, both detached and mass transferring, in the Galaxy; and possibly unforeseen sources such as the relic gravitational-wave radiation from the early Universe. eLISA's high signal-to-noise measurements will provide new insight into the structure and history of the Universe, and they will test general relativity in its strong-field dynamical regime.

Amaro-Seoane, Pau↗
NASA NTRS1978

Conference of Remote Sensing Educators (CORSE-78)

Ways of improving the teaching of remote sensing students at colleges and universities are discussed. Formal papers and workshops on various Earth resources disciplines, image interpretation, and data processing concepts are presented. An inventory of existing remote sensing and related subject courses being given in western regional universities is included.

Source record↗
NASA NTRS2006

The Evolution of the Cluster X-ray Scaling Relations in the Wide Angle ROSAT Pointed Survey Sample at 0.6 < z < 1.0

The X-ray properties of a sample of 11 high-redshift (0.6 < z < 1 .O) clusters observed with Chardm and/or XMM-Newton are used to investigate the evolution of the cluster scaling relations. The observed evolution in the normalization of the L-T, M-T, M(sub 2)-T and M-L relations is consistent with simple self-similar predictions, in which the properties of clusters reflect the properties of the Universe at their redshift of observation. Under the assumption that the model of self-similar evolution is correct and that the local systems formed via a single spherical collapse, the high-redshift L-T relation is consistent with the high-z clusters having virialized at a significantly higher redshift than the local systems. The data are also consistent with the more realistic scenario of clusters forming via the continuous accretion of material. The slope of the L-T relation at high redshift (B = 3.32 +/- 0.37) is consistent with the local relation, and significantly steeper than the self-similar prediction of B = 2. This suggests that the same non-gravitational processes are responsible for steepening the local and high-z relations, possibly occurring universally at z is approximately greater than 1 or in the early stages of the cluster formation, prior to their observation. The properties of the intracluster medium at high redshift are found to be similar to those in the local Universe. The mean surface-brightness profile slope for the sample is Beta = 0.66 +/- 0.05, the mean gas mass fractions within R(sub 2500(z)) and R(200(z)) are 0.069 +/- 0.012 and 0.11 +/- 0.02, respectively, and the mean metallicity of the sample is 0.28 +/- 0.11 Z(sub solar).

Maughan, B. J.↗
NASA NTRS1998

Fifth International Conference on Squeezed States and Uncertainty Relations

The Fifth International Conference on Squeezed States and Uncertainty Relations was held at Balatonfured, Hungary, on 27-31 May 1997. This series was initiated in 1991 at the College Park Campus of the University of Maryland as the Workshop on Squeezed States and Uncertainty Relations. The scientific purpose of this series was to discuss squeezed states of light, but in recent years the scope is becoming broad enough to include studies of uncertainty relations and squeeze transformations in all branches of physics including quantum optics and foundations of quantum mechanics. Quantum optics will continue playing the pivotal role in the future, but the future meetings will include all branches of physics where squeeze transformations are basic. As the meeting attracted more participants and started covering more diversified subjects, the fourth meeting was called an international conference. The Fourth International Conference on Squeezed States and Uncertainty Relations was held in 1995 was hosted by Shanxi University in Taiyuan, China. The fifth meeting of this series, which was held at Balatonfured, Hungary, was also supported by the IUPAP. In 1999, the Sixth International Conference will be hosted by the University of Naples in 1999. The meeting will take place in Ravello near Naples.

Han, D.↗
NASA NTRS2005

Confirmation Of Thick Whim At Z-0.1 In Sculptor Supercluster

This grant is associated to an XMM observation of the quasar QSO Q0056-363(PI: Dr. Roberto Maiolino), which is one of the brightest quasars in the X-ray sky, and it lies in the general direction of the Sculptor Supercluster, and behind it. We requested the observation to check a previous hint of existence of an absorption features by highly ionized gas at the redshift of the Supercluster, which we supposed to be the imprint of a Warm-Hot Intergalactic Medium filament connecting the already virialized structures in the Supercluster. The observation suffered a high background, and so the net exposure was considerably reduced compared to the requested exposure. Additionally the quasar turned out to be in a quite low level of activity. These two unfortunate facts made it impossible to confirm or rule-out at high resolution (i.e. with the RGS) the existence of the previously hinted OW1 K-alpha resonant line at the redshift of the Sculptor Supercluster, the new RGS data being sensitive only to equivalent width of unresolved absorption lines of about 30-50 mA at 1-sigma. The data, however, shows a very strong absorption line in a position different from the OVII/OVIII K-alpha at the redshift of the Supercluster. If this line is interpreted as OVII/OVIII K-alpha absorption, the redshift of this WHIM filament would lie in a region of the Universe where no visible virialized concentrations are present. This would confirm the relatively high probability of detecting WHIM filaments in apparent 'void' regions of the Universe (as previously suggested by our first detection of WHIM filaments at z greater than 0 along the line of sight to the blazar Mkn 421). A paper on the non-detection of any WHIM filament at the redshift of the Sculptor Supercluster, as well as on the detection of this putative WHIM filament in a 'void', will be shortly submitted to the ApJ.

Nicastro, Fabrizio↗
NASA NTRS1983

Radiation budget measurement/model interface

This final report includes research results from the period February, 1981 through November, 1982. Two new results combine to form the final portion of this work. They are the work by Hanna (1982) and Stevens to successfully test and demonstrate a low-order spectral climate model and the work by Ciesielski et al. (1983) to combine and test the new radiation budget results from NIMBUS-7 with earlier satellite measurements. Together, the two related activities set the stage for future research on radiation budget measurement/model interfacing. Such combination of results will lead to new applications of satellite data to climate problems. The objectives of this research under the present contract are therefore satisfied. Additional research reported herein includes the compilation and documentation of the radiation budget data set a Colorado State University and the definition of climate-related experiments suggested after lengthy analysis of the satellite radiation budget experiments.

Vonderhaar, T. H.↗
NASA NTRS2009

Merging Black Holes, Gravitational Waves, and Numerical Relativity

The final merger of two black holes will emit more energy than all the stars in the observable universe combined. This energy will come in the form of gravitational waves, which are a key prediction of Einstein's general relativity and a new tool for exploring the universe. Observing these mergers with gravitational wave detectors, such as the ground-based LIGO and the space-based LISA, requires knowledge of the radiation waveforms. Since these mergers take place in regions of extreme gravity, we need to solve Einstein's equations of general relativity on a computer. For more than 30 years, scientists have tried to compute black hole mergers using the methods of numerical relativity. The resulting computer codes were long plagued by instabilities, causing them to crash well before the black holes in the binary could complete even a single orbit. Within the past few years, however, this situation has changed dramatically, with a series of remarkable breakthroughs. This talk will focus on new simulations that are revealing the dynamics and w ae~fo rms of binary black hole mergers, and their applications in gravitational wave detection, testing general relativity, and astrophysics.

Centrella, Joan M.↗
NASA NTRS1983

Four-dimensional symmetry from a broad viewpoint. II Invariant distribution of quantized field oscillators and questions on infinities

The foundation of the quantum field theory is changed by introducing a new universal probability principle into field operators: one single inherent and invariant probability distribution P(/k/) is postulated for boson and fermion field oscillators. This can be accomplished only when one treats the four-dimensional symmetry from a broad viewpoint. Special relativity is too restrictive to allow such a universal probability principle. A radical length, R, appears in physics through the probability distribution P(/k/). The force between two point particles vanishes when their relative distance tends to zero. This appears to be a general property for all forces and resembles the property of asymptotic freedom. The usual infinities in vacuum fluctuations and in local interactions, however complicated they may be, are all removed from quantum field theories. In appendix A a simple finite and unitary theory of unified electroweak interactions is discussed without assuming Higgs scalar bosons.

Hsu, J. P.↗
NASA NTRS1972

Studies relating to FM television and telemetry transmitters

The Auburn University Model S-2 FM television transmitter was examined to determine if the performance and reliability could be improved by application of new techniques and devices developed since completion of the original design work. In particular this study examined the possibility of increased use of integrated circuits. It was determined that improvements in both performance and reliability were possible. In addition a study was conducted to determine the feasibility of converting the transmitter to handle telemetry signals. The study revealed that this conversion was feasible and the modifications were made to the prototype model for verification.

Albritton, W. P.↗