19 research outputs found
Collaborative Software Development Approach Used to Deliver the New Shuttle Telemetry Ground Station
United Space Alliance (USA) developed and used a new software development method to meet technical, schedule, and budget challenges faced during the development and delivery of the new Shuttle Telemetry Ground Station at Kennedy Space Center. This method, called Collaborative Software Development, enabled KSC to effectively leverage industrial software and build additional capabilities to meet shuttle system and operational requirements. Application of this method resulted in reduced time to market, reduced development cost, improved product quality, and improved programmer competence while developing technologies of benefit to a small company in California (AP Labs Inc.). Many modifications were made to the baseline software product (VMEwindow), which improved its quality and functionality. In addition, six new software capabilities were developed, which are the subject of this article and add useful functionality to the VMEwindow environment. These new software programs are written in C or VXWorks and are used in conjunction with other ground station software packages, such as VMEwindow, Matlab, Dataviews, and PVWave. The Space Shuttle Telemetry Ground Station receives frequency-modulation (FM) and pulse-code-modulated (PCM) signals from the shuttle and support equipment. The hardware architecture (see figure) includes Sun workstations connected to multiple PCM- and FM-processing VersaModule Eurocard (VME) chassis. A reflective memory network transports raw data from PCM Processors (PCMPs) to the programmable digital-to-analog (D/A) converters, strip chart recorders, and analysis and controller workstations
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Evaluation of innovative arsenic treatment technologies :the arsenic water technology partnership vendors forums summary report.
The lowering of the drinking water standard (MCL) for arsenic from 50 {micro}g/L to 10 {micro}g/L in January 2006 could lead to significant increases in the cost of water for many rural systems throughout the United States. The Arsenic Water Technology Partnership (AWTP), a collaborative effort of Sandia National Laboratories, the Awwa Research Foundation (AwwaRF) and WERC: A Consortium for Environmental Education and Technology Development, was formed to address this problem by developing and testing novel treatment technologies that could potentially reduce the costs of arsenic treatment. As a member of the AWTP, Sandia National Laboratories evaluated cutting-edge commercial products in three annual Arsenic Treatment Technology Vendors Forums held during the annual New Mexico Environmental Health Conferences (NMEHC) in 2003, 2004 and 2005. The Forums were comprised of two parts. At the first session, open to all conference attendees, commercial developers of innovative treatment technologies gave 15-minute talks that described project histories demonstrating the effectiveness of their products. During the second part, these same technologies were evaluated and ranked in closed sessions by independent technical experts for possible use in pilot-scale field demonstrations being conducted by Sandia National Laboratories. The results of the evaluations including numerical rankings of the products, links to company websites and copies of presentations made by the representatives of the companies are posted on the project website at http://www.sandia.gov/water/arsenic.htm. This report summarizes the contents of the website by providing brief descriptions of the technologies represented at the Forums and the results of the evaluations
Hemodynamic Effects of Anthrax Toxins in the Rabbit Model and the Cardiac Pathology Induced by Lethal Toxin
Anthrax lethal toxin (LeTx) and edema toxin (EdTx) have been shown to alter hemodynamics in the rodent model, while LeTx primarily is reported to induce extensive tissue pathology. However, the rodent model has limitations when used for comparison to higher organisms such as humans. The rabbit model, on the other hand, has gained recognition as a useful model for studying anthrax infection and its pathophysiological effects. In this study, we assessed the hemodynamic effects of lethal toxin (LeTx) and edema toxin (EdTx) in the rabbit model using physiologically relevant amounts of the toxins. Moreover, we further examine the pathological effects of LeTx on cardiac tissue. We intravenously injected Dutch-belted rabbits with either low-dose and high-dose recombinant LeTx or a single dose of EdTx. The animals’ heart rate and mean arterial pressure were continuously monitored via telemetry until either 48 or 72 h post-challenge. Additional animals challenged with LeTx were used for cardiac troponin I (cTnI) quantitation, cardiac histopathology, and echocardiography. LeTx depressed heart rate at the lower dose and mean arterial pressure (MAP) at the higher dose. EdTx, on the other hand, temporarily intensified heart rate while lowering MAP. Both doses of LeTx caused cardiac pathology with the higher dose having a more profound effect. Lastly, left-ventricular dilation due to LeTx was not apparent at the given time-points. Our study demonstrates the hemodynamic effects of anthrax toxins, as well as the pathological effects of LeTx on the heart in the rabbit model, and it provides further evidence for the toxins’ direct impact on the heart
The Long-Baseline Neutrino Experiment: Exploring Fundamental Symmetries of the Universe
The preponderance of matter over antimatter in the early Universe, the
dynamics of the supernova bursts that produced the heavy elements necessary for
life and whether protons eventually decay --- these mysteries at the forefront
of particle physics and astrophysics are key to understanding the early
evolution of our Universe, its current state and its eventual fate. The
Long-Baseline Neutrino Experiment (LBNE) represents an extensively developed
plan for a world-class experiment dedicated to addressing these questions. LBNE
is conceived around three central components: (1) a new, high-intensity
neutrino source generated from a megawatt-class proton accelerator at Fermi
National Accelerator Laboratory, (2) a near neutrino detector just downstream
of the source, and (3) a massive liquid argon time-projection chamber deployed
as a far detector deep underground at the Sanford Underground Research
Facility. This facility, located at the site of the former Homestake Mine in
Lead, South Dakota, is approximately 1,300 km from the neutrino source at
Fermilab -- a distance (baseline) that delivers optimal sensitivity to neutrino
charge-parity symmetry violation and mass ordering effects. This ambitious yet
cost-effective design incorporates scalability and flexibility and can
accommodate a variety of upgrades and contributions. With its exceptional
combination of experimental configuration, technical capabilities, and
potential for transformative discoveries, LBNE promises to be a vital facility
for the field of particle physics worldwide, providing physicists from around
the globe with opportunities to collaborate in a twenty to thirty year program
of exciting science. In this document we provide a comprehensive overview of
LBNE's scientific objectives, its place in the landscape of neutrino physics
worldwide, the technologies it will incorporate and the capabilities it will
possess.Comment: Major update of previous version. This is the reference document for
LBNE science program and current status. Chapters 1, 3, and 9 provide a
comprehensive overview of LBNE's scientific objectives, its place in the
landscape of neutrino physics worldwide, the technologies it will incorporate
and the capabilities it will possess. 288 pages, 116 figure
Genome-wide structural variant analysis identifies risk loci for non-Alzheimer’s dementias
We characterized the role of structural variants, a largely unexplored type of genetic variation, in two non-Alzheimer’s dementias, namely Lewy body dementia (LBD) and frontotemporal dementia (FTD)/amyotrophic lateral sclerosis (ALS). To do this, we applied an advanced structural variant calling pipeline (GATK-SV) to short-read whole-genome sequence data from 5,213 European-ancestry cases and 4,132 controls. We discovered, replicated, and validated a deletion in TPCN1 as a novel risk locus for LBD and detected the known structural variants at the C9orf72 and MAPT loci as associated with FTD/ALS. We also identified rare pathogenic structural variants in both LBD and FTD/ALS. Finally, we assembled a catalog of structural variants that can be mined for new insights into the pathogenesis of these understudied forms of dementia
Flammability limits of ammonia-air mixtures
In an attempt to increase the level of understanding of ammonia combustion, this paper presents the results of a recent study of the flammability limits of ammonia-air mixtures. In the past, these studies have been conducted using a flame tube to determine the flammability limits of the gas. The study reported here used the ASTM E 681-85 (ASTM 1985) standard method. Even though the flammability limits of ammonia have been established in the past, it was necessary to determine the limits using this relatively new method, since it is drastically different from any previously used method. A brief but complete literature review is provided, followed by a discussion of the flammability testing apparatus and experimental results. The measured upper and lower flammability limits in dry air were 27.35% and 15.15%, respectively. In air with a relative humidity of 100%, the upper and lower flammability limits narrowed to 15.95% and 26.55%, respectively
Combustion characteristics review of ammonia-air mixtures
Ammonia as a refrigerant presents both combustion safety concerns and interest regarding disposal in a flare under controlled combustion conditions. These two aspects involve the combustion characteristics of ammonia. The literature was reviewed with the objective of identifying the technical information pertinent to combustion safety and performance as a fuel. Ammonia\u27s flammability limits in air at standard atmospheric conditions are 14.8% (lower flammability limit, LFL) and 33.5% (upper flammability limit, UFL) concentration of ammonia by volume in air. Lower pressures tend to narrow the flammability limits and, as temperature increases, the LFL is decreased. The presence of water vapor was noted to narrow the flammability limits. Ignition energy requirements, burning velocity, and explosion hazards are also reviewed. More information is required to ascertain the effect of ammonia liquid droplets and lubricating oil, both possible components of a release at a refrigeration plant, on the combustion characteristics of ammonia
Operating characteristics of a flare/oxidizer for the disposal of ammonia from an industrial refrigeration facility
The disposal of ammonia released from an industrial refrigeration facility may be accomplished by combustion in a flare or oxidizer. An experimental chamber was fabricated whereby a venturi section separated the combustion zone from the mixing chamber where the supply gases entering were mixed. Using natural gas as the pilot fuel, the flare was operated over the entire flammable region where the combustion temperature and exhaust products were measured. For lean fuel (ammonia and natural gas) combustion conditions and ammonia supply content less than 10% of the total by volume, the ammonia exhaust concentrations were less than 5 ppm. However, the NO concentrations over the same region sometimes exceeded 1,000 ppm. Mineral, paraffinic, and polyester-based oils in weight concentrations 20% and above with ammonia reduced the lower flammability limit (LFL) of ammonia-air mixtures to 12%, 9%, and 8% by volume, respectively. The injection of liquid ammonia to the natural gas pilot flame yielded exhaust ammonia concentrations less than 5 ppm when ammonia to natural gas mass ratios were less than 0.5.
Catalyst : Celebrating 25 Years of Fanshawe College Fine Arts
On the occasion of an exhibition of works by 46 Fanshawe graduates, members of the college community recount the establishment and development of the fine arts programme. Includes brief artists' statements. 1 bibl. ref