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This report analyzes the workings of the “Real - time Adaptive Acceleration of Dynamic Experimental Science” LDRD team, led by James Ahrens, Cindy Bolme and Richard Sandberg, using it to outline practices of successful and innovative LDRD collaborations.
This report summarizes the activities, technical accomplishments, and outcomes of the RAPIDS2 Institute project at the University of Delaware (UD). The RAPIDS2 Institute was a large multi-institution project with the objective of assisting SciDAC and Office of Science application teams in the use of DOE supercomputing resources to achieve scientific breakthroughs. The UD team contributed to this effort through work on formal software verification. This thrust aims to reduce software developer time and effort, especially regarding debugging and testing, and to increase confidence in the correctness of the results computed by the software.
BSC TO5 Task 7.1 Field Testing Unvented Roofs with Asphalt Shingles in Cold Climates - Bolingbrook, IL 60440 BSC TO5 Task 7.1 Field Testing Unvented Roofs with Asphalt Shingles in Hot-Humid Climates - Friendswood, TX 77546 To understand the long-term moisture performance of unvented roof assemblies with fibrous insulation, the U.S. Department of Energy's Building America team Building Science Corporation built and monitored test roofs in two climates: a cold-climate test house in Bolingbrook, Illinois (Chicago area; zone 5A), and a hot-humid test house in Friendswood, Texas (Houston area, zone 2A). The Chicago-area test bed had seven parallel experimental rafter bays. The assemblies included a control vented compact (cathedral) roof, a dense-pack cellulose unvented roof, and an unvented roof with a "diffusion vent" (a strip of vapor-permeable gypsum sheathing at the ridge to allow drying). The interior finish was gypsum wallboard (GWB) with latex paint. The other four bays were top vent roof assemblies, which have a polypropylene breather mesh between the roof sheathing and the asphalt shingles to allow ventilation drying of the assembly from underneath the vapor-impermeable shingles. Two of the four "top vent" roofs were fiberglass batt and two were dense-pack cellulose roofs with either interior GWB or open to the interior. Wintertime moisture-related failure was accelerated by providing interior humidification (22.2 degree C [72 degree F]/50% relative humidity [RH]), which is known to be an extreme interior loading). Data were captured over 8 months, including a winter and the following spring and early summer.
BSC TO5 Task 2.5 Field Testing of an Un-vented Roof with Fibrous Insulation and Tiles - Winter Park, FL 32789 Field test data available for wood moisture contents, temperature, and relative humidity. Un-vented roofs (aka cathedral-ized attics) are an established presence in Florida residential building markets. These roofs are built with a layer of spray polyurethane foam (SPF) on the underside of the roof deck. Such a roof configuration positions the heating, ventilating, and air-conditioning equipment and ductwork within the conditioned space and improves airtight-ness in practice (by shifting the air barrier from the ceiling to the roofline). However, SPF is more expensive than fibrous insulation. Some builders have also become wary of using SPF because of liability concerns about indoor air quality and off-gassing. Unfortunately, un-vented roofs that use only air-permeable fibrous insulation (cellulose or fiberglass) have been demonstrated to be at risk of moisture issues in climate zone 2A because condensation and moisture accumulation occur at the ridge. This report describes research about a test implementation of an un-vented tile roof assembly in a hot-humid climate (Orlando, Florida; climate zone 2A); the roof was insulated with air-permeable insulation (netted and blown fiberglass). Given the localized moisture accumulation and failures seen in previous work, the U.S. Department of Energy's Building America research team Building Science Corporation theorized that installation of diffusion vents might allow for the wintertime release of moisture to safe levels. Diffusion vents are open slots at the roof's highest points (the ridge and hips) that are covered with a water-resistant but vapor-open (500+ perm) air barrier membrane. The test home is a two-story slab-on-grade structure (3,600 ft2 ); the roof was insulated with a prototype insulation system (called boxed netting), which allows full depth insulation (i.e., it is not limited by the depth of the truss top chord). As a control comparison, one part of the roof was constructed as a typical un-vented roof (with a self-adhered membrane at the ridge). Ideally, failure would occur in the control roof and the experimental (diffusion vent) roofs would show sufficient drying to avoid failure. No intentional space conditioning was provided in the un-vented attic so worst-case humidity buildup conditions could be observed.
The Wide Field InfraRed Survey Telescope (WFIRST) was the highest-ranked large space-based mission of the 2010 New Worlds, New Horizons decadal survey. It is now a NASA mission in formulation with a planned launch in the mid 2020s. A primary mission objective is to precisely constrain the nature of dark energy through multiple probes, including Type Ia supernovae (SN Ia). Here, we present the first realistic simulations of the WFIRST SN survey based on current hardware specifications and using open-source tools. We simulate SN light curves and spectra as viewed by the WFIRST wide-field channel (WFC) imager and integral field channel (IFC) spectrometer, respectively. We examine 11 survey strategies with different time allocations between the WFC and IFC, two of which are based upon the strategy described by the WFIRST Science Definition Team, which measures SN distances exclusively from IFC data. We propagate statistical and, crucially, systematic uncertainties to predict the Dark Energy Task Force figure of merit (FoM) for each strategy. Of the strategies investigated, we find the most successful to be WFC focused. However, further work in constraining systematics is required to fully optimize the use of the IFC. Even without improvements to other cosmological probes, the WFIRST SN survey has the potential to increase the FoM by more than an order of magnitude from the current values. Although the survey strategies presented here have not been fully optimized, these initial investigations are an important step in the development of the final hardware design and implementation of the WFIRST mission.
This document presents updated estimates, as of May 2022, of the Rubin system throughput and compares them to throughput requirements from the LSST Science Requirements Document. In addition, it uses these estimates to forecast LSST's median single-visit and co-added image depths for the current (OpSim v2.0) baseline LSST cadence simulation: (23.8, 24.5, 24.0, 23.4, 22.7, 22.0) and (25.6, 26.9, 26.9, 26.4, 25.6, 24.8) in ugrizy, respectively. In addition, it uses these estimates to forecast LSST’s median single-visit and co-added image depths for the current baseline LSST cadence simulation. Estimated system performance relies on actual measurements of the performance of various system hardware components, and on simulations where measurements are still unavailable. The updated performance estimates meet all the relevant requirements from the LSST Science Requirements Document. As our knowledge of the as-buit system continues to improve, updates to these estimates will continue to be provided.
Special Programs are additional survey areas and/or observing strategies that are driven by specific science goals which build on, or are beyond, the core science pillars of the Wide Fast Deep Main Survey. In order to meet the requirements and enable science related to Special Programs, this document provides recommendations for Rubin Data Management regarding processing and serving data products for Special Programs. Hardware and processing boundaries on the potential diversity of data from Special Programs are discussed along with scenarios in which user-generated processing and data products might be needed to meet Special Programs' science goals.
A quantitative review of the key numbers associated with the Legacy Survey of Space and Time (LSST) Alert Stream.
The scientific analyses of photographic data in astronomy obtained by the Apollo Orbital Science Photographic Team during Apollo flights 14 through 17 are described. Some of the tasks are the collection and correlation of Quick-Look listings, working prints for further study, the generation of post-mission reports, and project reports. Postflight calibrations of the flight photographic systems are carried out, and lens vignetting effects are corrected. The data handling is described and includes photodigitization of photographic scenes, calibrated step-wedges, and vignetting patterns, which are followed by computer program processing of the film density readings.
Major aerospace companies are talking about space factories manufacturing billions of dollars worth of high technology materials per year. On the other hand, a recent National Academy of Sciences study team saw little prospect for space manufacturing because, in their opinion, most of the disturbing effects of gravity in the processes they considered could be overcome on the ground for much less expenditure. This paper presents a current assessment of the problems and promises of the Materials Processing in Space Program and outlines a strategy for developing the first products of commercial value. These early products are expected to serve as paradigms of what can be accomplished by manufacturing in space and should stimulate industry to develop space manufacturing to whatever degree is economically justifiable.
The key science requirements, the overall design, and the innovative testing approaches that have been used to ensure the functionality of the Alaska SAR Facility (ASF) are described. The facility is to play an important role in the remote sensing applications of Arctic oceanography, geology, glaciology, hydrology, and ecosystem processes. Attention is given to the ASF's three major components: the Receiving Ground Station, the SAR Processing System, and the Archive and Operations System. The ASF hardware configuration and software support, through extensive design and implementaton reviews, were shown to satisfy the initial memorandum of agreement first initiated by NASA for the establishment of a receiving ground station and image processing facility at the University of Alaska Fairbanks, and also to satisfy the science objectives formulated by the prelaunch Science Working team. The testing strategy and techniques used in the implementation of the ASF to assure functionality is outlined. The test structures, approach, and environment are considered.
On 18 Jan. 1991, NASA confirmed 29 Inter-Disciplinary Science (IDS) teams, each involving a group of investigators, to conduct interdisciplinary research using data products from Earth Observing System (EOS) instruments. These studies are multi-disciplinary and require output data products from multiple EOS instruments, including both FI and PI instruments. The purpose of this volume is to provide information on output products expected from IDS investigators, required input data, and retrieval algorithms. Also included in this volume is the revised analysis of the 'best' and 'alternative' match data products for IDS input requirements. The original analysis presented in the August 1991 release of the SPSO Report was revised to incorporate the restructuring of the EOS platform. As a result of the reduced EOS payload, some of EOS instruments were deselected and their data products would not be available for IDS research. Information on these data products is also presented.
Past co-operation between the NASA Earth Science and Applications Division and the CSIRO and Australian university researchers has led to a number of mutually beneficial activities. These include the deployment of the C-130 aircraft with TIMS, AIS, and NS001 sensors in Australia in 1985; collaboration between scientists from the USA and Australia in soils research which has extended for the past decade; and in the development of imaging spectroscopy where DSIRO and NASA have worked closely together and regularly exchanged visiting scientists. In May this year TIMS was flown in eastern Australia on board a CSIRO-owned aircraft together with a CSIRO-designed CO2 laser spectrometer. The Science Investigation Team for the Shuttle Imaging Radar (SIRC-C) Program includes one Australian Principal Investigator and ten Australian co-investigators who will work on nine projects related to studying land and near-shore surfaces after the Shuttle flight scheduled for April 1994. This long-term continued joint collaboration was progressed further with the deployment of AIRSAR downunder in September 1993. During a five week period, the DC-8 aircraft flew in all Australian states and collected data from some 65 individual test sites.
This effort was for the participation of Dr. William S. Kurth in the study of the application of spacecraft using solar electric propulsion (SEP) for a range of space physics missions. This effort included the participation of Dr. Kurth in the Tropix Science Definition Team but also included the generalization to various space physics and planetary missions, including specific Explorer mission studies.
Swift is a multi-wavelength observatory specifically designed to detect transients sources in the gamma-ray energy band 15-200 keV. The primary goals of the mission involve gamma ray burst (GRB) astronomy, namely to determine the origin of GRBs and their afterglows, and use bursts to probe the early Universe. However, Swift will also discover new X-ray transient sources, and it will be possible to bring Swift's considerable multi-wavelength capabilities to bear on these sources, and those discovered by other means. The Burst Alert Telescope (BAT) is a coded mask instrument sensitive to 15-200 keV gamma rays, and has a field of view which covers approximately 1/8th of the sky in a single pointing. Over a typical observing day, the almost the entire sky will be observed and monitored for new transient sources. Sources will be detected within several hours of observation. The two narrow field instruments, the X-ray Telescope and Ultra-Violet Optical Telescope, can provide sensitive simultaneous imaging and spectroscopy observations in the optical through soft X-ray bands. The Swift science operations team will entertain requests for targets of opportunity for sources which are astrophysically significant. Swift will be ideally suited for the detection of transients which produce hard X-rays, such as black hole binaries and some neutron star systems.
Searching for evidence of life on Mars will probably require access to the subsurface. The Martian surface is bathed in ultraviolet radiation which decomposes organic compounds, destroying possible evidence for life. Also, experiments performed by the Viking Landers imply the presence of several strongly oxidizing compounds at the Martian surface that may also play a role in destroying organic compounds near the surface. While liquid water is unstable on the Martian surface, and ice is unstable at the surface at low latitudes, recent results from the Mars Odyssey Gamma Ray Spectrometer experiment indicate that water ice is widely distributed near the surface under a thin cover of dry soil. Organic compounds created by an ancient Martian biosphere might be preserved in such ice-rich layers. Furthermore, accessing the subsurface provides a way to identify unique stratigraphy such as small-scale layering associated with lacustrine sediments. Subsurface access might also provide new insights into the Mars climate record that may be preserved in the Polar Layered Deposits. Recognizing the importance of accessing the subsurface of Mars to the future scientific exploration of the planet, the Mars Surveyor 2007 Science Definition Team called for drilling beneath the surface soils. Subsurface measurements are also cited as high priority in by MEPAG. Recognizing the importance of accessing the Martian subsurface to search for life, the European Space Agency has incorporated a small automated burrowing device called a subsurface penetrometer or Mole onto the Beagle 2 lander planned for 2003 launch. This device, called the Planetary Underground Tool (PLUTO), is a pointed slender cylinder 2 cm wide and 28 cm long equipped with a small sampling device at the pointed end that collects samples and brings them to the surface for analysis. Drawing on the PLUTO design, we are developing a larger Mole carrying sensors for identifying mineralogy, organic compounds, and water.
We present the initial results from our study of the nonthermal continuum emission from the supernova remnants Cassiopeia A, MSB 11-61-4, a d CT-4 1. We used the INTEGRAL Core Program data to conduct this study. During the INTEGRAL mission a significant fraction of the total observing time (e.g. 35% in year one) is allocated to the Core Program and is analyzed under the auspices of the INTEGRAL Science Working Team. We report no statistically significant detections thus far but we will continue to analyze the data as more is taken. The results so far are consistent with previous measurements from e.g. RXTE and ASCA.
Neurolab is a NASA Spacelab mission with multinational cooperative participation that is dedicated to research on the nervous system. The nervous systems of all animal species have evolved in a one-g environment and are functionally influenced by the presence of gravity. The absence of gravity presents a unique opportunity to gain new insights into basic neurologic functions as well as an enhanced understanding of physiological and behavioral responses mediated by the nervous system. The primary goal of Neurolab is to expand our understanding of how the nervous system develops, functions in, and adapts to microgravity space flight. Twenty-six peer reviewed investigations using human and nonhuman test subjects were assigned to one of eight science discipline teams. Individual and integrated experiments within these teams have been designed to collect a wide range of physiological and behavior data in flight as well as pre- and postflight. Information from these investigations will be applicable to enhancing the well being and performance of future long duration space travelers, will contribute to our understanding of normal and pathological functioning of the nervous system, and may be applied by the medical community to enhance the health of humans on Earth.