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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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At least 217 records · Page 12

Study of space shuttle orbiter system management computer function. Volume 1: Analysis, baseline design

A system analysis of the shuttle orbiter baseline system management (SM) computer function is performed. This analysis results in an alternative SM design which is also described. The alternative design exhibits several improvements over the baseline, some of which are increased crew usability, improved flexibility, and improved growth potential. The analysis consists of two parts: an application assessment and an implementation assessment. The former is concerned with the SM user needs and design functional aspects. The latter is concerned with design flexibility, reliability, growth potential, and technical risk. The system analysis is supported by several topical investigations. These include: treatment of false alarms, treatment of off-line items, significant interface parameters, and a design evaluation checklist. An in-depth formulation of techniques, concepts, and guidelines for design of automated performance verification is discussed.

Source record↗

Parametric study of thermal storage containing rocks or fluid filled cans for solar heating and cooling, phase 2

The test data and an analysis of the heat transfer characteristics of a solar thermal energy storage bed utilizing water filled cans and standard bricks as energy storage medium are presented. This experimental investigation was initiated to find a usable heat intensive solar thermal storage device other than rock storage and water tank. Four different sizes of soup cans were stacked in a chamber in three different arrangements-vertical, horizontal, and random. Air is used as transfer medium for charging and discharge modes at three different mass flow rates and inlet air temperature respectively. These results are analyzed and compared, which show that a vertical stacking and medium size cans with Length/Diameter (L/D) ratio close to one have better average characteristics of heat transfer and pressure drop.

Saha, H.↗

Aviation safety research and transportation/hazard avoidance and elimination

Data collected by the Scanning Laser Doppler Velocimeter System (SLDVS) was analyzed to determine the feasibility of the SLDVS for monitoring aircraft wake vortices in an airport environment. Data were collected on atmospheric vortices and analyzed. Over 1600 landings were monitored at Kennedy International Airport and by the end of the test period 95 percent of the runs with large aircraft were producing usable results in real time. The transport was determined in real time and post analysis using algorithms which performed centroids on the highest amplitude in the thresholded spectrum. Making use of other parameters of the spectrum, vortex flow fields were studied along with the time histories of peak velocities and amplitudes. The post analysis of the data was accomplished with a CDC-6700 computer using several programs developed for LDV data analysis.

Sonnenschein, C. M.↗

Automated image processing of LANDSAT 2 digital data for watershed runoff prediction

The U.S. Soil Conservation Service (SCS) model for watershed runoff prediction uses soil and land cover information as its major drivers. Kern County Water Agency is implementing the SCS model to predict runoff for 10,400 sq cm of mountainous watershed in Kern County, California. The Remote Sensing Unit, University of California, Santa Barbara, was commissioned by KCWA to conduct a 230 sq cm feasibility study in the Lake Isabella, California region to evaluate remote sensing methodologies which could be ultimately extrapolated to the entire 10,400 sq cm Kern County watershed. Digital results indicate that digital image processing of Landsat 2 data will provide usable land cover required by KCWA for input to the SCS runoff model.

Sasso, R. R.↗

Simulating the Dynamics of Earth's Core: Using NCCS Supercomputers Speeds Calculations

If one wanted to study Earth's core directly, one would have to drill through about 1,800 miles of solid rock to reach liquid core-keeping the tunnel from collapsing under pressures that are more than 1 million atmospheres and then sink an instrument package to the bottom that could operate at 8,000 F with 10,000 tons of force crushing every square inch of its surface. Even then, several of these tunnels would probably be needed to obtain enough data. Faced with difficult or impossible tasks such as these, scientists use other available sources of information - such as seismology, mineralogy, geomagnetism, geodesy, and, above all, physical principles - to derive a model of the core and, study it by running computer simulations. One NASA researcher is doing just that on NCCS computers. Physicist and applied mathematician Weijia Kuang, of the Space Geodesy Branch, and his collaborators at Goddard have what he calls the,"second - ever" working, usable, self-consistent, fully dynamic, three-dimensional geodynamic model (see "The Geodynamic Theory"). Kuang runs his model simulations on the supercomputers at the NCCS. He and Jeremy Bloxham, of Harvard University, developed the original version, written in Fortran 77, in 1996.

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Enceladus: Biosignatures

Saturn's moon Enceladus is a new world for Astrobiology. Through the study of Enceladus' plumes new insights into its habitability will be gained. The four core parameters for life include: water, carbon, nitrogen, and energy; all were found in the plume. Carbon and nitrogen in the plume exist in forms easily usable by biological systems (CH4, HCN, NH3, H2, CO2, and organics up to C6). The first step to search for evidence of life is to define potential biosignatures for Enceladus.

Amino Acids↗

Development of a preprototype vapor compression distillation water recovery subsystem

The activities involved in the design, development, and test of a preprototype vapor compression distillation water recovery subsystem are described. This subsystem, part of a larger regenerative life support evaluation system, is designed to recover usable water from urine, urinal rinse water, and concentrated shower and laundry brine collected from three space vehicle crewmen for a period of 180 days without resupply. Details of preliminary design and testing as well as component developments are included. Trade studies, considerations leading to concept selections, problems encountered, and test data are also presented. The rework of existing hardware, subsystem development including computer programs, assembly verification, and comprehensive baseline test results are discussed.

Johnson, K. L.↗

Technical communication in aeronautics - Results of an exploratory study

A study was undertaken that explored several aspects of technical communications in aeronautics. The study utilized survey research. A self-administered mail questionnaire was sent to 2,000 randomly selected members of the American Institute of Aeronautics and Astronautics (AIAA) in the U.S. with academic, government, or industrial affiliations. Six hundred and six (606) usable questionnaires were received. The findings add considerable information to the knowledge of technical communications among aeronautical engineers and scientists; reinforce some of the conventional wisdom about technical communications and question other widely-held notions; and hold significant implications for technical communicators, information managers, research and development managers, and curriculum developers.

Pinelli, Thomas E.↗

Qualitative Analysis for Maintenance Process Assessment

In order to improve software maintenance processes, we first need to be able to characterize and assess them. These tasks must be performed in depth and with objectivity since the problems are complex. One approach is to set up a measurement-based software process improvement program specifically aimed at maintenance. However, establishing a measurement program requires that one understands the problems to be addressed by the measurement program and is able to characterize the maintenance environment and processes in order to collect suitable and cost-effective data. Also, enacting such a program and getting usable data sets takes time. A short term substitute is therefore needed. We propose in this paper a characterization process aimed specifically at maintenance and based on a general qualitative analysis methodology. This process is rigorously defined in order to be repeatable and usable by people who are not acquainted with such analysis procedures. A basic feature of our approach is that actual implemented software changes are analyzed in order to understand the flaws in the maintenance process. Guidelines are provided and a case study is shown that demonstrates the usefulness of the approach.

Brand, Lionel↗

ISS Propulsion Module Crew Systems Interface Analysis in the Intelligent Synthesis Environment

ERGO, a human modeling software for ergonomic assessment and task analysis, was used for the crew systems interface analysis of the International Space Station (ISS) Propulsion Module (PM). The objective of analysis was to alleviate passageway size concerns. Three basic passageway configuration concepts: (1) 45" clear passageway without centerline offset (2) 50" clear passageway, 12" centerline offset, (3) 50" clear passageway, no centerline offset, and were reviewed. 95 percentile male and female models which were provided by the software performed crew system analysis from an anthropometric point of view. Four scenarios in which the crew floats in microgravity through a 50" no-offset passageway as they carry a 16" x 20" x 30" avionics box were simulated in the 10-weeks of intensive study. From the results of the analysis, concept (3) was the preferred option. A full scale, three-dimensional virtual model of the ISS Propulsion Module was created to experience the sense of the Intelligent Synthesis Environment and to evaluate the usability and applicability of the software.

Chen, Di-Wen↗

Dynamics of playa lakes in the Texas High Plains

The author has identified the following significant results. Three small playa lake basins on the southern High Plains, Texas, have been examined by geologists, pedologists, hydrologists, and botanists to establish ground truth for correlation with ERTS-1 imagery. Although the sites are recognizable, details of the three playa basins are too small, at present resolution, to be accurately determined by the available MSS imagery. However, a fourth study site, consisting of a dual playa complex approximately 5 miles long in a basin of 9 square miles, does resolve available imagery allowing accurate measurement of water fluctuations and water depth. Of the available MSS imagery, Band 5 is the most usable. Definition of Band 4 is less due to reduced tonal contrast. The greatest tonal contrast appears on Band 6 and Band 7 between dry land and water areas. Band 6 is particularly good for defining large water areas, Band 7 being best for small lake basins, and Band 5 for growing fields.

Reeves, C. C., Jr.↗

Space shuttle phase B extension, volume 1

In order to define a system which would significantly reduce payload delivery costs, activities were extended to modifications of the reusable space shuttle design concept. Considered were systems using orbiters with external propellant tanks and an interim expendable booster which allowed phased development of the usable orbiter and booster. Analyzed were: Merits of internal and external propellant tanks and the impact of external LH2 compared to L02 and LH2; impact of cargo bay size; impact abort; merit of expendable booster options; and merit of a phased development program. Studies showed that external L02/LH2 and the continued use of the J-2S engine on the orbiter reduced program cost and risk.

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NASA Applications Data Service

The NASA Applications Data Service (ADS), which is being developed to provide timely, affordable access to readily usable multisource data products and services for NASA-affliliated space-technology applications researchers, is presented. The system concept of a decentralized information network, which retrieves data from existing data bases and provides it to the user, has been adopted, and feasibility studies of the compatibility of the ADS with other existing or planned network data systems are under way. Other current efforts include the definition of the requirements and services necessary to support NASA applications experiments and encourage private industry to design the system and commercially implement it, as well as applications scenarios support, commercialization potential, standards identification, and concept justification with respect to future applications missions.

Brown, L. E.↗

Shuttle ground operations efficiencies/technologies study. Volume 4: Preliminary Issues Database (PIDB) catalog

The Preliminary Issues Database (PIDB) was assembled very early in the study as one of the fundamental tools to be used throughout the study. Data was acquired from a variety of sources and compiled in such a way that the data could be easily sorted in accordance with a number of different analytical objectives. The system was computerized to significantly expedite sorting and make it more usable. The information contained in the PIDB is summarized and the reader is provided with the capability to manually find items of interest.

Scholz, A. L.↗

NASA gateway requirements analysis

NASA devotes approximately 40 percent of its budget to R&D. Twelve NASA Research Centers and their contractors conduct this R&D, which ranges across many disciplines and is fueled by information about previous endeavors. Locating the right information is crucial. While NASA researchers use peer contacts as their primary source of scientific and technical information (STI), on-line bibliographic data bases - both Government-owned and commercial - are also frequently consulted. Once identified, the STI must be delivered in a usable format. This report assesses the appropriateness of developing an intelligent gateway interface for the NASA R&D community as a means of obtaining improved access to relevant STI resources outside of NASA's Remote Console (RECON) on-line bibliographic database. A study was conducted to determine (1) the information requirements of the R&D community, (2) the information sources to meet those requirements, and (3) ways of facilitating access to those information sources. Findings indicate that NASA researchers need more comprehensive STI coverage of disciplines not now represented in the RECON database. This augmented subject coverage should preferably be provided by both domestic and foreign STI sources. It was also found that NASA researchers frequently request rapid delivery of STI, in its original format. Finally, it was found that researchers need a better system for alerting them to recent developments in their areas of interest. A gateway that provides access to domestic and international information sources can also solve several shortcomings in the present STI delivery system. NASA should further test the practicality of a gateway as a mechanism for improved STI access.

Duncan, Denise R.↗

Knowledge-based critiquing of graphical user interfaces with CHIMES

CHIMES is a critiquing tool that automates the process of checking graphical user interface (GUI) designs for compliance with human factors design guidelines and toolkit style guides. The current prototype identifies instances of non-compliance and presents problem statements, advice, and tips to the GUI designer. Changes requested by the designer are made automatically, and the revised GUI is re-evaluated. A case study conducted at NASA-Goddard showed that CHIMES has the potential for dramatically reducing the time formerly spent in hands-on consistency checking. Capabilities recently added to CHIMES include exception handling and rule building. CHIMES is intended for use prior to usability testing as a means, for example, of catching and correcting syntactic inconsistencies in a larger user interface.

Jiang, Jianping↗

Crew Roles and Interactions in Scientific Space Exploration

Future piloted space exploration missions will focus more on science than engineering, a change which will challenge existing concepts for flight crew tasking and demand that participants with contrasting skills, values, and backgrounds learn to cooperate as equals. In terrestrial space flight analogs such as Desert Research And Technology Studies, engineers, pilots, and scientists can practice working together, taking advantage of the full breadth of all team members training to produce harmonious, effective missions that maximize the time and attention the crew can devote to science. This paper presents, in a format usable as a reference by participants in the field, a successfully tested crew interaction model for such missions. The model builds upon the basic framework of a scientific field expedition by adding proven concepts from aviation and human spaceflight, including expeditionary behavior and cockpit resource management, cooperative crew tasking and adaptive leadership and followership, formal techniques for radio communication, and increased attention to operational considerations. The crews of future spaceflight analogs can use this model to demonstrate effective techniques, learn from each other, develop positive working relationships, and make their expeditions more successful, even if they have limited time to train together beforehand. This model can also inform the preparation and execution of actual future spaceflights.

Love, Stanley G.↗

Are we ready for the first EASA guidance on the use of ML in Aviation?

NASA has been working for the past 12 years on software tools for the assurance of software in Aviation critical systems. For now two years, NASA has focused more on the use of AI-based techniques in Aviation than the traditional software systems used in the past. The primary focus has been on machine learning (ML), and more specifically, on supervised off-line learning ML systems. NSA’s research has been driven by case studies such as a vision-based centerline tracking system (implemented using deep neural networks) and the new generation of collision avoidance systems developed under the FAA guidance, i.e., the family of ACAS-X products. Since EASA has recently released its first usable guidance for Level 1 machine learning applications, it is opportunity to see how the research done at NASA is mapping to this first guidance for ML. In this talk I will use the EASA guidance document as a guide to present the past, present, and future tools and techniques being developed at NASA. The intent is to not only provide an overview of the research effort at NASA but also to see how this effort is addressing the concerns listed in the EASA first usable guidance for ML.

Guillaume Brat↗