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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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For small photon numbers, trapping states are difficult to detect due to the influence of the collective effects. We find that if the atoms are injected with atomic polarization, the micromaser becomes more insensitive to these effects. In particular, the squeezing properties of the cotangent states are basically unchanged.
The Universal Multizone Crystallizator (UMC) is a special apparatus for crystal growth under terrestrial and microgravity conditions. The use of twenty-five zones allows the UMC to be used for several normal freezing growth techniques. The thermal profile is electronically translated along the stationary sample by systematically reducing the power to the control zones. Elimination of mechanical translation devices increases the systems reliability while simultaneously reducing the size and weight. This paper addresses the UMC furnace design, sample cartridge and typical thermal profiles and corresponding power requirements necessary for the dynamic gradient freeze crystal growth technique. Results from physical vapor transport and traveling heater method crystal growth experiments are also discussed.
Based on this review, the following conclusions are drawn regarding the 'school readiness' of the sites. All six of the sites had great appeal to the reviewers and therefore we can conclude that each has tremendous potential for use in the classroom. None, however, were given a completely 'school-ready' assessment. With recommended revisions, each site will be a valuable asset to the classroom teacher. For each as well, teachers particularly had problems with access or finding them, but once there, felt they all had some relevance. Many of the weaknesses noted related to lack of guidance for teachers with links to their curriculum or provision of activities. Other weaknesses related to the lack of educational purpose, however, this may be addressed in the development of strong teacher resources and guides linked to the sites. For those sites with a weak or without a teacher's guide, adding this component would be worth the expenditure of time and money needed.
In many years of research, a number of powerful theorem-proving systems have arisen with differing capabilities and strengths. Resolution theorem provers (such as Kestrel's KITP or SRI's SNARK) deal with first-order logic with equality but not the principle of mathematical induction. The Boyer-Moore theorem prover excels at proof by induction but cannot deal with full first-order logic. Both are highly automated but cannot accept user guidance easily. The purpose of this project, and the companion project at Kestrel, has been to use the category-theoretic notion of logic morphism to combine systems with different logics and languages.
Several areas of work related to commercialization of technology developed at NASA Ames Research Center (ARC) are discussed in this report. The areas are: (1) perform a feasibility study to develop a software commercialization center is at ARC; (2) perform preliminary work for formation of joint development of sensor technology for telemedicine applications; (3) development of a discovery interview process and staff training to assist the commercialization of technology developed at Ames, specifically aimed at working with researchers; (4) develop partners to further develop and commercialize image compression technology developed at AMES; (5) assist efforts to commercialize a software technology which imparts the ability to establish relevance-based retrieval in the handling of large repositories of information; (6) explore the development of cryocooler technology using pulse tube refrigeration; (7) assess interest in commercialization of a new method of measuring skin friction drag on wind tunnel models using liquid crystal material; (8) attempt to incorporate emerging technologies in the infrastructure of natural hazards mitigation; and (9) forming a nonprofit organization, "The Bootstrap Alliance", whose mission is to promote the use of digital technologies for collaborative problem solving. The results of these initiatives are discussed.
Reliable estimates of exposures due to ionizing radiations are of paramount importance in achieving human exploration and development of space, and in several technologically important and scientifically significant areas impacting on industrial and public health. For proper assessment of radiation exposures reliable transport codes are needed. An essential input to the transport codes is the information about the interaction of ions and neutrons with the matter. Most of the information about this interaction is put in by nuclear cross section data. In order to obtain an accurate parameterization of cross sections data, theoretical input is indispensable especially for the processes where there is little or no experimental data available. In the grant period reliable data base was developed and a phenomenological model was developed for the total absorption cross sections valid for any charged/uncharged light, medium and heavy collision pairs valid for the entire energy range. It is gratifying to note the success of the model. The cross sections model has been adopted and is in use in NASA cosmic ray detector development projects, the radiation protection and shielding programs and several DoE laboratories and institutions. A list of the publications based on the work done during the grant period is given below and a sample copy of one of the papers is enclosed with this report.
The origin of the Geotail Program and the collaboration with Japan traces back to the Origin of Plasmas in the Earth's Neighborhood (OPEN) Program, a fleet of four spacecraft studied at the National Aeronautics and Space Administration (NASA) Goddard Space Flight Center (GSFC) in the early 1980s to conduct multipoint, coordinated measurements in the Earth's magnetosphere and the interplanetary medium. The OPEN program was the natural evolution of the early discovery missions, which although finding many new regions and plasmaphysical phenomena in the magnetosphere had problems separating cause-and effect relationships and resolving space-time ambiguities. The primary scientific objective was the coordinated study of the flow of energy, mass, and momentum from the Sun through the interplanetary medium and its eventual deposition in the Earth's atmosphere. This objective was to be achieved in a quantitative manner and to that extent theory, models, and ground-based observations were incorporated for the first time as an integral part of the project baseline. An ambitious ground system, capable of processing and visualizing the vast amounts of data generated by these spacecraft, was also conceived and incorporated in the OPEN concept.
This poster is an invitation for participation in the specification and implementation of engineering and ancillary data standards, and allied software tools needed to conceptualize, designs, operate and analyze the data returned from Mars and other solar system exploration missions
Vertical ozone profiles between the Equator and 10 S latitude available from the Southern Hemisphere Additional Ozone (SHADOZ) program provide consistent data Ozone sets from up to 10 sounding locations. SHADOZ designed to provide independent ozone profiles in the tropics for evaluation of satellite ozone data and models has made available over 600 soundings over the period 1998-1999. These observations provide an ideal data base for the detailed description of ozone and afford differential comparison between sites. TOMS total ozone when compared with correlative integrated total ozone overburden from the sondes is found to be negatively biased when using the classical constant mixing ratio procedure to determine residual ozone. On the other hand, the climatological method proposed by McPeters and Labow appears to give consistent results but is positively biased. The longer then two years series of measurements also was subjected to harmonic analysis to examine data cycles. These will be discussed as well.
The project is concerned with the development of decision-theoretic techniques to optimize the scientific return of planetary rovers. Planetary rovers are small unmanned vehicles equipped with cameras and a variety of sensors used for scientific experiments. They must operate under tight constraints over such resources as operation time, power, storage capacity, and communication bandwidth. Moreover, the limited computational resources of the rover limit the complexity of on-line planning and scheduling. We have developed a comprehensive solution to this problem that involves high-level tools to describe a mission; a compiler that maps a mission description and additional probabilistic models of the components of the rover into a Markov decision problem; and algorithms for solving the rover control problem that are sensitive to the limited computational resources and high-level of uncertainty in this domain.
MSST2004, the Twelfth NASA Goddard / Twenty-first IEEE Conference on Mass Storage Systems and Technologies has as its focus long-term stewardship of globally-distributed storage. The increasing prevalence of e-anything brought about by widespread use of applications based, among others, on the World Wide Web, has contributed to rapid growth of online data holdings. A study released by the School of Information Management and Systems at the University of California, Berkeley, estimates that over 5 exabytes of data was created in 2002. Almost 99 percent of this information originally appeared on magnetic media. The theme for MSST2004 is therefore both timely and appropriate. There have been many discussions about rapid technological obsolescence, incompatible formats and inadequate attention to the permanent preservation of knowledge committed to digital storage. Tutorial sessions at MSST2004 detail some of these concerns, and steps being taken to alleviate them. Over 30 papers deal with topics as diverse as performance, file systems, and stewardship and preservation. A number of short papers, extemporaneous presentations, and works in progress will detail current and relevant research on the MSST2004 theme.
The viability of a Capillary Heat Pump (CHP) concept using a Loop Heat Pipe evaporator and an eductor in a closed loop to reject heat at a higher temperature than it is acquired at with the goal of reducing spacecraft radiator area is examined. Eductor inefficiency resulting from the mixing of high velocity motive flow with low velocity suction flow may preclude spacecraft radiator area savings. The utility of a CHP for thermal management may be limited to those missions where system mass is of secondary concern compared to system reliability, or where a heat pump is required to accommodate relatively high thermal rejection temperatures. Shearography techniques for nondestructive inspection and evaluation were examined for two unique applications. Shearography is shown to give good results in evaluating the quality of bonds holding lead tiles to the SWIFT spacecraft BAT gamma ray mask. Also, a novel technique was developed allowing specular objects to be inspected using shearography to evaluate bonding between the skin and core of a specular surface honeycomb structure. Large-scale bond failures are readily identified.
This report describes research undertaken by USRA scientists working in the NASA Space Science Directorate laboratories at Goddard Space Flight Center.
The Centers for Disease Control and Prevention (CDC) is coordinating HELIX- Atlanta to provide information regarding the five-county Metropolitan Atlanta Area (Clayton, Cobb, DeKalb, Fulton, and Gwinett) via a network of integrated environmental monitoring and public health data systems so that all sectors can take action to prevent and control environmentally related health effects. The HELIX-Atlanta Network is a tool to access interoperable information systems with optional information technology linkage functionality driven by scientific rationale. HELIX-Atlanta is a collaborative effort with local, state, federal, and academic partners, including the NASA Marshall Space Flight Center. The HELIX-Atlanta Partners identified the following HELIX-Atlanta initial focus areas: childhood lead poisoning, short-latency cancers, developmental disabilities, birth defects, vital records, respiratory health, age of housing, remote sensing data, and environmental monitoring, HELIX-Atlanta Partners identified and evaluated information systems containing information on the above focus areas. The information system evaluations resulted in recommendations for what resources would be needed to interoperate selected information systems in compliance with the CDC Public Health Information Network (PHIN). This presentation will discuss the collaborative process of building a network that links health and environment data for information exchange, including NASA remote sensing data, for use in HELIX-Atlanta.
Since its inception in January 2003, the program has provided support for 1 faculty, 1 research scientist. 1 research assistant, and a total of 7 Graduate Research Scholar Assistants, of these all 7 have gram. The program has generated 4 MS thesis. Attachment: Appendix A, B, C, and D.
It is well known that fires in the low-gravity environment of Earth-orbiting spacecraft are different from fires on Earth. The flames lack the familiar upward plume, which is the result of gravitational buoyancy. These flames, however, are strongly influenced by minor airflow currents. A recent study conducted in low gravity (microgravity) on the Russian orbital station Mir used burning plastic rods mounted in a small chamber with a controllable fan to expose the flame to airflows of different velocities. In this unique project, a Russian scientific agency, the Keldysh Research Center, furnished the apparatus and directed the Mir tests, while the NASA Glenn Research Center at Lewis Field provided the test materials and the project management. Reference testing and calibrations in ground laboratories were conducted jointly by researchers at Keldysh and at the NASA Johnson Space Center's White Sands Test Facility. Multiple samples of three different plastics were burned in the tests: Delrin, a common material for valve bodies; PMMA, a plastic "glass"; and polyethylene, a familiar material for containers and films. Each burned with a unique spherical or egg-shaped flame that spread over the rod. The effect of varying the airflow was dramatic. At the highest airflow attainable in the combustion chamber, nearly 10 cm/sec (a typical ventilation breeze), the flames were bright and strong. As airflow velocity decreased, the flames became shorter but wider. In addition, the flames became less bright, and for PMMA and polyethylene, they showed two colors, a bright part decreasing in volume and a nearly invisible remainder (see the photographs). Finally, at a very low velocity, the flames extinguished. For the plastics tested, this minimum velocity was very low, around 0.3 to 0.5 cm/sec. This finding confirms that at least a slight airflow is required to maintain a flame in microgravity for these types of materials.
The International Space Station Program Office (ISSPO) has organized a consolidated program to provide communication, education, and outreach to the general public. Existing space station education programs, including amateur radio activities on ISS done voluntarily by the crew members, can be linked to additional classroom and field activities, multiplying the impact of this very scarce and valuable Station resource. Linkages could be created between programs such as Starshine, Space Camp Turkey, MISSES/PCSAT2, and Amateur Radio on ISS. In addition, Amateur radio provides a means of introducing school children to technical hardware and concepts while being fun for the youthful mind. Amateur radio can reach the worldwide community while remaining within very affordable budgets of schools and individuals. When the radio communication is coupled with the Internet, the effect is even greater. People in many diverse areas of the world have access to the internet or radio.
Situation management is a rapidly evolving science where managed sources are processed as realtime streams of events and fused in a way that maximizes comprehension, thus enabling better decisions for action. Sensor networks provide a new technology that promises ubiquitous input and action throughout an environment, which can substantially improve information available to the process. Here we describe a NASA program that requires improvements in sensor networks and situation management. We present an approach for massively deployed sensor networks that does not rely on centralized control but is founded in lessons learned from the way biological ecosystems are organized. In this approach, fully distributed data aggregation and integration can be performed in a scalable fashion where individual motes operate based on local information, making local decisions that achieve globally-meaningful results. This exemplifies the robust, fault-tolerant infrastructure required for successful situation management systems.