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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 91 records · Page 5

General Temporal Knowledge for Planning and Data Mining

We consider the architecture of systems that combine temporal planning and plan execution and introduce a layer of temporal reasoning that potential1y improves both the communication between humans and such systems, and the performance of the temporal planner itself. In particular, this additional layer simultaneously supports more flexibility in specifying and maintaining temporal constraints on plans within an uncertain and changing execution environment, and the ability to understand and trace the progress of plan execution. It is shown how a representation based on single set of abstractions of temporal information can be used to characterize the reasoning underlying plan generation and execution interpretation. The complexity of such reasoning is discussed.

Morris, Robert↗

Observational Tests of the Mars Ocean Hypothesis: Selected MOC and MOLA Results

We have begun a detailed analysis of the evidence for and topography of features identified as potential shorelines that have been im-aged by the Mars Orbiter Camera (MOC) during the Aerobraking Hiatus and Science Phasing Orbit periods of the Mars Global Surveyor (MGS) mission. MOC images, comparable in resolution to high-altitude terrestrial aerial photographs, are particularly well suited to address the morphological expressions of these features at scales comparable to known shore morphologies on Earth. Particularly useful are examples of detailed relationships between potential shore features, such as erosional (and depositional) terraces have been cut into "familiar" pre-existing structures and topography in a fashion that points to a shoreline interpretation as the most likely mechanism for their formation. Additional information is contained in the original extended abstract.

Parker, T. J.↗

Geologist's Field Assistant: Developing Image and Spectral Analyses Algorithms for Remote Science Exploration

We are developing science analyses algorithms to interface with a Geologist's Field Assistant device to allow robotic or human remote explorers to better sense their surroundings during limited surface excursions. Our algorithms will interpret spectral and imaging data obtained by various sensors. Additional information is contained in the original extended abstract.

Gulick, V. C.↗

International Symposium on Remote Sensing of Environment, 7th, University of Michigan, Ann Arbor, Mich., May 17-21, 1971, Proceedings. Volumes 1, 2 & 3.

The sessions dealt in full detail with basic research in geology and soils; manual interpretation of data on land use, snow, and ice; machine assisted data handling; instrumentation; basic research in water, snow, and ice; manual interpretation of data on vegetation, soils, and geology; user studies and instrumentation; and operational systems. Individual items are abstracted in this issue.

Source record↗

Evidence for Ancient Martian Life

Three SNC meteorites ranging in age from 4.5 Ga. to 1.3 Ga. to 165 m.y. contain features suggestive of past biogenic activity on Mars. Because we do not know what past martian life looks like or its physical or chemical properties, the only tools or criteria which the scientific community have to evaluate evidence of past life is to use evidence for early life on earth. There are features within ALH84001's carbonate globules and the preterrestrial aqueous alteration phases of Nakhla and Shergotty which have been interpreted as possible evidence for past life on early Mars. Additional information is contained in the original extended abstract.

Gibson, E. K., Jr.↗

Possible Evidence for Life in ALH84001

Since our original paper in Science in August 1996, considerable new data has appeared from laboratories throughout the world, and our own team has had a chance to examine the sample in greater detail. The following summary touches on our original data and interpretation, and points out new data from us and from other groups, and the resulting changes and refinements in interpretations which we have made during the past three years. Additional information is contained in the original extended abstract.

McKay, David↗

Investigation of atmospheric waves on Neptune

This document constitutes the final report for grant NAGW-2442 of the Neptune Data Analysis Program, which supported research concerning atmospheric dynamics on Neptune. Professor Von R. Eshleman was the principal investigator. David P. Hinson was a Co-Investigator. The grant covered the period 1 March 1991 through 31 August 1994, including a six month no-cost extension. Funding from this grant resulted in publication of one journal article and one book chapter as well as presentation of results at two conferences and in numerous seminars. A complete bibliography is given below. A copy of the journal article is attached along with abstracts from the book chapter and the conference presentations. With support from this grant we extended our analysis and interpretation of the Voyager Project. This research contributed to an improvement in our basic understanding of atmospheric dynamics on Neptune. The highlight was the discovery and characterization of inertio-gravity waves in the troposphere and stratosphere. Results include measures of basic wave properties, such as amplitudes and vertical wavelengths, as well as estimates of the effect of the waves on the photochemistry and momentum balance of the stratosphere. This investigation also yielded a better understanding of the potential of radio occultation experiments for studies of atmospheric waves. At the same time we developed new methods of data analysis for exploiting these capabilities. These are currently being applied to radio occultation data obtained with the Magellan spacecraft to study waves in the atmosphere of Venus. Future planetary missions, such as Mars Global Surveyor and Cassini, will benefit from these accomplishments.

Eshleman, Von R.↗

A study of the use of abstract types for the representation of engineering units in integration and test applications

Physical quantities using various units of measurement can be well represented in Ada by the use of abstract types. Computation involving these quantities (electric potential, mass, volume) can also automatically invoke the computation and checking of some of the implicitly associable attributes of measurements. Quantities can be held internally in SI units, transparently to the user, with automatic conversion. Through dimensional analysis, the type of the derived quantity resulting from a computation is known, thereby allowing dynamic checks of the equations used. The impact of the possible implementation of these techniques in integration and test applications is discussed. The overhead of computing and transporting measurement attributes is weighed against the advantages gained by their use. The construction of a run time interpreter using physical quantities in equations can be aided by the dynamic equation checks provided by dimensional analysis. The effects of high levels of abstraction on the generation and maintenance of software used in integration and test applications are also discussed.

Johnson, Charles S.↗

A low-density boundary-layer wind tunnel facility

This abstract describes a low-density wind-tunnel facility that was established at NASA Ames in order to aid interpretation and understanding of data received from the Mariner and Viking spacecraft through earth-based simulation. The wind tunnel is a boundary-layer type which is capable of operating over a range of air densities ranging from 0.01 to 1.24 kg/cu m, with the lower values being equivalent to the near-surface density of the planet Mars. Although the facility was developed for space and extraterrestrial simulation, it also can serve as a relatively large-scale, low-density aerodynamic test facility. A description of this unique test facility and some Pitot-tube and hot-wire anemometry data acquired in the facility are presented.

White, B. R.↗

Hydrogen Isotopic Composition of Water in the Martian Atmosphere and Released from Rocknest Fines

The Mars Science Laboratory Curiosity rover sampled the aeolian bedform called Rocknest as its first solid samples to be analyzed by the analytical instruments CheMin and SAM. The instruments ingested aliquots from a sieved sample of less than 150 micrometer grains. As discussed in other reports at this conference [e.g., 1], CheMin discovered many crystalline phases, almost all of which are igneous minerals, plus some 10s of percent of x-ray amorphous material. The SAM instrument is focused on understanding volatiles and possible organics in the fines, performing evolved gas analysis (EGA) with the SAM quadrapole mass spectrometer (QMS), isotope measurements using both the QMS and the tunable laser spectrometer (TLS), which is sensitive to CO2, water and methane, and organics with the gas chromatograph mass spectrometer (GCMS). As discussed in the abstract by Franz et al. [2] and others, EGA of Rocknest fines revealed the presence of significant amounts of H2O as well as O-, C- and S-bearing materials. SAM has also tasted the martian atmosphere several times, analyzing the volatiles in both the TLS and QMS [e.g., 3,4]. This abstract will focus on presentation of initial hydrogen isotopic data from the TLS for Rocknest soils and the atmosphere, and their interpretation. Data for CO2 isotopes and O isotopes in water are still being reduced, but should be available by at the conference.

Leshin, L. A.↗

Galilean Satellite Surface Non-Ice Constituents: New Results from the Cassini/Huygens VIMS Jupiter Flyby in the Context of the Galileo NIMS Results

The Cassini mission Visible and Infrared Mapping Spectrometer (VIMS) is currently returning data for the Galilean satellites. Examples of the new satellite data and the initial interpretations will be presented in the context of the Galileo NIMS data and results. Additional information is contained in the original extended abstract.

McCord, T. B.↗

Cosmic Ray Astronomy

The cosmic ray division participation in the cooperative agreement was activated in the second year. The scientific goals will be analysis of cosmic ray data from the Japanese-American Cooperative Emulsion Experiments (JACEE). Measurements of primary cosmic rays in the JACEE emulsion chambers will be made to derive for each detected particle the deposited energy in the chamber and the primary charge (atomic number). The data will be corrected to the primary flux above the atmosphere, and the composition and energy spectra will be derived. The spectra of the individual elements will be interpreted in context with the supernova shock and other models of cosmic ray acceleration. Additional information is contained in the original extended abstract.

Wu, S. T.↗

LISP: Data is program. A tutorial in LISP

A novel approach at teaching LISP to a novice was developed. The abstract data format is presented, emphasizing its real structure and its machine implantation. Then the technique of writing programs in the data language, and of interpreting them, is presented. Illustrative features are drawn from various extant LISP implementations.

White, J. L.↗

EVA Glove Sensor Feasbility II Abstract

The main objectives for the glove project include taking various measurements from human subjects during and after they perform different tasks in the glove box, acquiring data from these tests and determining the accuracy of these results, interpreting and analyzing this data, and using the data to better understand how hand injuries are caused during EVAs.1 Some of these measurements include force readings, temperature readings, and micro-circulatory blood flow.1 The three glove conditions tested were ungloved (a comfort glove was worn to house the sensors), Series 4000, and Phase VI. The general approach/procedure for the glove sensor feasibility project is as follows: 1. Prepare test subject for testing. This includes attaching numerous sensors (approximately 50) to the test subject, wiring, and weaving the sensors and wires in the glove which helps to keep everything together. This also includes recording baseline moisture data using the Vapometer and MoistSense. 2. Pressurizing the glove box. Once the glove box is pressurized to the desired pressure (4.3 psid), testing can begin. 3. Testing. The test subject will perform a series of tests, some of which include pinching a load cell, making a fist, pushing down on a force plate, and picking up metal pegs, rotating them 90 degrees, and placing them back in the peg board. 4. Post glove box testing data collection. After the data is collected from inside the glove box, the Vapometer and MoistSense device will be used to collect moisture data from the subject's hand. 5. Survey. At the conclusion of testing, he/she will complete a survey that asks questions pertaining to comfort/discomfort levels of the glove, glove sizing, as well as offering any additional feedback.

Melone, Kate↗

Scattering models in the microwave regime

Results of first and second year research efforts are summarized in a series of complete articles and abstracts. The goal of the first year efforts was to calculate scattering from an inhomogeneous layer with irregular boundaries to model natural terrains. The model was applied to interpret measurements from vegetation, snow, and sea ice. The goal of the second year was to extend the scattering model to handle disc shaped scatterers which are comparable to incident wavelength and to use the model to investigate the relative merits between active versus passive sensing of soil moisture over vegetated terrain.

Fung, A. K.↗

Domain specific software design for decision aiding

McDonnell Aircraft Company (MCAIR) is involved in many large multi-discipline design and development efforts of tactical aircraft. These involve a number of design disciplines that must be coordinated to produce an integrated design and a successful product. Our interpretation of a domain specific software design (DSSD) is that of a representation or framework that is specialized to support a limited problem domain. A DSSD is an abstract software design that is shaped by the problem characteristics. This parallels the theme of object-oriented analysis and design of letting the problem model directly drive the design. The DSSD concept extends the notion of software reusability to include representations or frameworks. It supports the entire software life cycle and specifically leads to improved prototyping capability, supports system integration, and promotes reuse of software designs and supporting frameworks. The example presented in this paper is the task network architecture or design which was developed for the MCAIR Pilot's Associate program. The task network concept supported both module development and system integration within the domain of operator decision aiding. It is presented as an instance where a software design exhibited many of the attributes associated with DSSD concept.

Keller, Kirby↗