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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 307 records · Page 17

Reasoning by analogy as an aid to heuristic theorem proving.

When heuristic problem-solving programs are faced with large data bases that contain numbers of facts far in excess of those needed to solve any particular problem, their performance rapidly deteriorates. In this paper, the correspondence between a new unsolved problem and a previously solved analogous problem is computed and invoked to tailor large data bases to manageable sizes. This paper outlines the design of an algorithm for generating and exploiting analogies between theorems posed to a resolution-logic system. These algorithms are believed to be the first computationally feasible development of reasoning by analogy to be applied to heuristic theorem proving.

Kling, R. E.↗

Application of remote sensing to state and regional problems

Mississippi State University was awarded a grant by NASA to effect remote sensing technology transfer in Mississippi and the Mid-South region and to demonstrate the operational uses of remoting sensing in providing the basic data and information necessary to solve problems of state and regional nature. Thus, the primary purpose of the Remote Sensing Applications Program at Mississippi State University is for members of the University community to participate in activities that improve effective communication between the scientific community engaged in remote sensing research and development, and the potential users of modern remote sensing technology. The state-of-the-art remote sensing capability is significantly beyond the present-day applications of the potential user group. The program services to accelerate the operational use of proven remote sensing technology which will help to insure reasonable pay-off from the better usage of space, high altitude, and other remote sensing products evolved by the NASA program. Outputs of this program are assisting the State of Mississippi in recognizing and solving its environmental resource planning, and socio-economic sensing system.

W Frank Miller↗

Relation of the lunar power system to the SEI program and to landers

The people of Earth will need more than 20,000 billion watts (GWe) of electric power by 2050 for a high level of prosperity. Power needs in the 22nd Century could exceed 100,000 GWe. By 2100 the total quantity of thermal energy used could fully deplete the known inventory (10(exp 7) GWt-Y) of all non-renewable sources on Earth except for deuterium and hydrogen for use in proposed fusion reactors. The labor, capital, and mass of power plants required to produce 1 GWe-Y of energy from present-day power plants is summarized. Fossil and nuclear plants respectively consume 80 to 190 M$ and 12 to 48 M$ of fuel per GWe-Y. The Lunar Power System (LPS) uses solar power bases on the moon to beam electric power to Earth. The LPS in the figure supplies load-following power to rectennas on Earth. Additional solar power conversion units are located across the lunar limb from their respective Earthward transmitting stations. LPS can be augmented by mirrors in polar orbit about the moon. The construction of rectennas on Earth determines the base cost (0.001s$/kWe-H) of LPS power. A manned International Lunar Base (ILB) can accelerate the development of LPS by providing the initial transportation and habitation facilities and base operations. ILB can greatly reduce up front costs and risks by emplacing a moderate scale LPS (1-100 GWe). LPS can accelerate the development of the ILB by providing greater funding than is reasonable to expect for purely scientific research. An international ILB/LPS program can foster world trust and prosperity.

Criswell, David R.↗

Analysis of pressure-broadened ozone spectra in the 3 micron region

This work involves the analysis of a series of McMath Fourier Transform Infrared (FTIR) spectra of ozone broadened by mixing with air (four different pressures), nitrogen (three pressures), or oxygen (three pressures). Each spectrum covers the region from 2396 to 4057 cm(-1). This study focused on the 3 sub nu sub 3 band in t 3000 to 3060 cm(-1). The band is analyzed by first dividing its region into small intervals containing a few well isolated absorption lines of reasonable intensity. Each of these small intervals is fit by multiple iterations of the nonlinear least squares program until residuals (the difference between calculated and observed spectrum, as a percent of the strongest intensity in the interval) are minimized to a reasonable value which corresponds to the noise level of the measured spectrum. Position, intensity, and half-width are recorded for later analysis. From the measured half-widths, a pressure broadening coefficient was determined for each absorption line. Pressure shifts were determined by comparing observed line positions in the spectra of the diluted ozone samples to tabulated line positions determined from spectra of pure gas samples. Comparisons to other work on ozone indicate that the broadening and shift coefficients determined in this study are consistent with those determined in other spectral regions.

Prochaska, Eleanor S.↗

An editor for the generation and customization of geometry restraints

Chemical restraints for use in macromolecular structure refinement are produced by a variety of methods, including a number of programs that use chemical information to generate the required bond, angle, dihedral, chiral and planar restraints. These programs help to automate the process and therefore minimize the errors that could otherwise occur if it were performed manually. Furthermore, restraint-dictionary generation programs can incorporate chemical and other prior knowledge to provide reasonable choices of types and values. However, the use of restraints to define the geometry of a molecule is an approximation introduced with efficiency in mind. The representation of a bond as a parabolic function is a convenience and does not reflect the true variability in even the simplest of molecules. Another complicating factor is the interplay of the molecule with other parts of the macromolecular model. Finally, difficult situations arise from molecules with rare or unusual moieties that may not have their conformational space fully explored. These factors give rise to the need for an interactive editor for WYSIWYG interactions with the restraints and molecule. Restraints Editor, Especially Ligands (REEL) is a graphical user interface for simple and error-free editing along with additional features to provide greater control of the restraint dictionaries in macromolecular refinement.

59 BASIC BIOLOGICAL SCIENCES↗

Integrated Data Collection Analysis (IDCA) Program - SSST Testing Methods

The Integrated Data Collection Analysis (IDCA) program is conducting a proficiency study for Small- Scale Safety and Thermal (SSST) testing of homemade explosives (HMEs). Described here are the methods used for impact, friction, electrostatic discharge, and differential scanning calorimetry analysis during the IDCA program. These methods changed throughout the Proficiency Test and the reasons for these changes are documented in this report. The most significant modifications in standard testing methods are: 1) including one specified sandpaper in impact testing among all the participants, 2) diversifying liquid test methods for selected participants, and 3) including sealed sample holders for thermal testing by at least one participant. This effort, funded by the Department of Homeland Security (DHS), is putting the issues of safe handling of these materials in perspective with standard military explosives. The study is adding SSST testing results for a broad suite of different HMEs to the literature. Ultimately the study will suggest new guidelines and methods and possibly establish the SSST testing accuracies needed to develop safe handling practices for HMEs. Each participating testing laboratory uses identical test materials and preparation methods wherever possible. The testing performers involved are Lawrence Livermore National Laboratory (LLNL), Los Alamos National Laboratory (LANL), Indian Head Division, Naval Surface Warfare Center, (NSWC IHD), Sandia National Laboratories (SNL), and Air Force Research Laboratory (AFRL/RXQL). These tests are conducted as a proficiency study in order to establish some consistency in test protocols, procedures, and experiments and to compare results when these testing variables cannot be made consistent.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

An Investigation of LED Street Lighting's Impact on Sky Glow

A significant amount of public attention has recently focused on perceived impacts of converting street lighting from incumbent lamp-based products to LED technology. Much of this attention pertains to the higher content of short wavelength light (commonly referred to as "blue light") of LEDs and its attendant influences on sky glow (a brightening of the night sky that can interfere with astronomical observation and may be associated with a host of other issues). The complexity of this topic leads to common misunderstandings and misperceptions among the public, and for this reason the U.S. Department of Energy Solid-State Lighting Program embarked on a study of sky glow using a well-established astronomical model to investigate some of the primary factors influencing sky glow. This report details the results of the investigation and attempts to present those results in terms accessible to the general lighting community. The report also strives to put the results into a larger context, and help educate interested readers on various topics relevant to the issues being discussed.

99 GENERAL AND MISCELLANEOUS↗

Evaluation of the 2018 Version of the Integrated Surveillance Program Database Pressure Equation

The Integrated Surveillance Program (ISP) Database Pressure Equation was developed to determine with reasonable certainty the total maximum pressure of hydrogen and other gases in packaged 3013 containers stored at Savannah River Site (SRS) in support of the destructive evaluation (DE) process. The pressure equation in the Department of Energy (DOE) 3013 Standard, “Standard for Stabilization, Packaging and Storage of Plutonium- Bearing Materials” (DOE-STD-3013-2004) used a bounding assumption that all the water is decomposed to form hydrogen. However, the results of Los Alamos National Laboratory (LANL) shelf-life experiments showed that hydrogen is consumed, and that the maximum pressures would not approach the design pressure of the 3013 container. Therefore, the ISP Database Pressure Equation was revised in 2008 to include terms for the generation of helium and hydrogen as a function of time, as well as the consumption of water and destruction of hydrogen based on shelf-life results. The 2008 ISP Database Pressure Equation provided a more reasonable estimate of the total maximum pressure in packaged 3013 containers than the pressure equation in versions of the 3013 Standard issued prior to 2018.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

LF467 concept definition

The LF467 concept is discussed. The LF467 is an advanced turbotip lift fan intended for application with the YJ97-GE-100 turbojet gas generator on a V/STOL transport research aircraft. The program objective was to define a fan that develops a reasonably high (1.30) fan pressure ratio consistent with propulsion requirements of a V/STOL research transport aircraft and that exhibits the ability to achieve a 100 PNdE overall noise objective through the use of modest additional installation treatment. The aerodynamic and mechanical designs of this system and the resulting configuration, weight, and noise predictions are presented.

Source record↗

An improved prediction method for the noise generated in flight by circular jets

A semi-empirical model for predicting the noise generated by jets exhausting from circular nozzles is presented and compared with small-scale static and simulated-flight data. The present method is an updated version of that part of the original NASA aircraft noise prediction program relating to circular jet noise. The earlier method agreed reasonably well with experimental static and flight data for jet velocities up to approximately 520 m/sec. The poorer agreement at higher jet velocities appeared to be due primarily to the manner in which supersonic convection effects were formulated. The purely empirical supersonic convection formulation is replaced in the present method by one based on theoretical considerations. Other improvements of an empirical nature were included based on model-jet/free-jet simulated-flight tests. The effects of nozzle size, jet velocity, jet temperature, and flight are included.

Stone, J. R.↗

US in-space electric propulsion experiments

Arcjet and ion propulsion offer potentially significant reductions in the mass of propulsion systems required for Earth orbiting satellites and planetary spacecraft. For this reason, they have been the subject of validation and demonstration programs. After examining the benefits of electric propulsion, this paper discusses the technology base for the Electric Propulsion Space Experiment (ESEX) arcjet demonstration experiment and the NASA Technology Application Readiness (NSTAR) ion propulsion validation program. As part of the Advanced Research Global Observation Spacecraft (ARGOS), ESEX will perform ten 15-min firings of a 30-kW ammonia arcjet. NASA's validation program, NSTAR, consists of two major elements: a ground-test element and an in-space experiment. The ground element will validate the life, integrability, and performance of low-power ion propulsion. The in-space element will demonstrate the feasibility of integrating and flying an ion propulsion system. The experiment will measure the interactions among the ion propulsion system, the host spacecraft, and the surrounding space plasma. It will provide a quantitative assessment of the ability of ground testing to replicate the in-space performance ion thrusters. By involving industry in NSTAR, a commercial source for this technology will be ensured. Furthermore, the successful completion of the NSTAR validation program will stimulate commercial and government (both civilian and military) uses of this technology.

Stocky, John F.↗

Reformulating Non-Monotonic Theories for Inference and Updating

We aim to help build programs that do large-scale, expressive non-monotonic reasoning (NMR): especially, 'learning agents' that store, and revise, a body of conclusions while continually acquiring new, possibly defeasible, premise beliefs. Currently available procedures for forward inference and belief revision are exhaustive, and thus impractical: they compute the entire non-monotonic theory, then re-compute from scratch upon updating with new axioms. These methods are thus badly intractable. In most theories of interest, even backward reasoning is combinatoric (at least NP-hard). Here, we give theoretical results for prioritized circumscription that show how to reformulate default theories so as to make forward inference be selective, as well as concurrent; and to restrict belief revision to a part of the theory. We elaborate a detailed divide-and-conquer strategy. We develop concepts of structure in NM theories, by showing how to reformulate them in a particular fashion: to be conjunctively decomposed into a collection of smaller 'part' theories. We identify two well-behaved special cases that are easily recognized in terms of syntactic properties: disjoint appearances of predicates, and disjoint appearances of individuals (terms). As part of this, we also definitionally reformulate the global axioms, one by one, in addition to applying decomposition. We identify a broad class of prioritized default theories, generalizing default inheritance, for which our results especially bear fruit. For this asocially monadic class, decomposition permits reasoning to be localized to individuals (ground terms), and reduced to propositional. Our reformulation methods are implementable in polynomial time, and apply to several other NM formalisms beyond circumscription.

Grosof, Benjamin N.↗

U.S. In-Space Electric Propulsion Experiments

Arcjet and ion propulsion offer potentially significant reductions in the mass of propulsion systems required for Earth orbiting satellites and planetary spacecraft. For this reason, they have been the subject of validation and demonstration programs. After examining the benefits of electric propulsion, this paper discusses the technology base for the Electric propulsion Space Experiment (ESEX) arcjet demonstration experiment and the NASA SEP Technology Application Readiness (NSTAR) ion propulsion validation program. As part of the Advanced Research and Global Observation Spacecraft (ARGOS), ESEX will perform ten 15-minute firings of a 30 kW ammonia arcjet. NASA's validation program, NSTAR, consists of two major elements: a ground-test element and an in-space experiment. The ground-test element will validate the life, intergrability, and performance of low-power ion propulsion. The in-space element will demonstrate the feasibility of integrating and flying an ion propulsion system. The experiment will measure the interactions among the ion propulsion system, the host spacecraft, and the surrounding space plasma; and it will provide a quantitative assessment of the ability of ground testing to replicate the in-space performance of ion thrusters. By involving industry in NSTAR, a commercial source for this technology will be ensured. Furthermore, the successful completion of the NSTAR validation program will stimulate commercial and government (both civilian and military) uses of this technology.

arcjet↗

Keeping Up, with the Crowd

High-level presentation explaining the innovation imperative (reason for crowdsourcing) in addition to NASA CoECI's crowdsourcing program and how it's been successful.

Crowdsourcing↗

What is Security? A perspective on achieving security

This presentation provides a perspective on achieving security in an organization. It touches upon security as a mindset, ability to adhere to rules, cultivating awareness of the reason for a security mindset, the quality of a security program, willingness to admit fault or acknowledge failure, peer review in security, science as a model that can be applied to the security profession, the security vision, security partnering, staleness in the security program, security responsibilities, and achievement of success over time despite the impossibility of perfection.

99 GENERAL AND MISCELLANEOUS↗

River Corridor Closure at DOE's Hanford Site - 12503

The discussion of Hanford's River Corridor will cover work that has already been completed plus the work remaining to be done. This includes the buildings, waste sites, and groundwater plumes in the 300 Area; large-scale burial ground remediation in the 600 Area; plutonium production reactor dismantling and 'cocooning' along the river; preservation of the world's first full-scale plutonium production reactor; removal of more than 14 million tons of contaminated soil and debris along the Columbia River shoreline and throughout the River Corridor; and the excavation of buried waste sites in the river shore area. It also includes operating an EPA-permitted low-level waste disposal facility in the central portion of the site. At the completions of cleanup in 2015, Hanford's River Corridor will be the largest closure project ever completed by the Department of Energy. Cleanup of the River Corridor has been one of Hanford's top priorities since the early 1990's. This urgency has been due to the proximity of hundreds of waste sites to the Columbia River. In addition, removal of the sludge from K West Basin, near the river, remains a high priority. This 220-square-mile area of the Hanford Site sits on the edge of the last free-flowing stretch of the Columbia River. The River Corridor portion of the Hanford Site includes the 100 and 300 Areas along the south shore of the Columbia River. The 100 Areas contain nine retired plutonium production reactors. These areas are also the location of numerous support facilities and solid and liquid waste disposal sites that have contaminated groundwater and soil. The 300 Area, located just north of the city of Richland, contains fuel fabrication facilities, nuclear research and development facilities, and their associated solid and liquid waste disposal sites that have contaminated groundwater and soil. In order to ensure that cleanup actions address all threats to human health and the environment, the River Corridor includes the adjacent areas that extend from the 100 Area and 300 Area to the Central Plateau. For sites in the River Corridor, remedial actions are expected to restore groundwater to drinking water standards and ensure that aquatic life in the Columbia River is protected by achieving ambient water quality standards. It is intended that these objectives be achieved, unless technically impracticable, within a reasonable timeframe. In those instances where remedial action objectives are not achievable in a reasonable time frame, or are determined to be technically impracticable, programs are being implemented to contain the plume, prevent exposure to contaminated groundwater, and evaluate further risk reduction opportunities as new technologies become available. River Corridor cleanup work also removes potential sources of contamination, which are close to the Columbia River, and places them on the Central Plateau for final disposal. The intent is to shrink the footprint of active cleanup to within the 75-square- mile area of the Central Plateau by removing excess facilities and remediating waste sites. Cleanup actions are supporting anticipated future land uses consistent with the Hanford Reach National Monument, where applicable, and the Hanford Comprehensive Land- Use Plan (DOE 1999). The River Corridor has been divided into six geographic decision areas to achieve source and groundwater remedy decisions. These decisions will provide comprehensive coverage for all areas within the River Corridor and will incorporate ongoing interim action cleanup activities. Cleanup levels will be achieved in order to support anticipated future land uses of conservation and preservation for most of this area and industrial use for the 300 Area. At the conclusion of cleanup actions, the federal government will implement long-term stewardship activities to ensure protection of human health and the environment. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Economical graphics display system for flight simulation avionics

During the past academic year the focal point of this project has been to enhance the economical flight simulator system by incorporating it into the aero engineering educational environment. To accomplish this goal it was necessary to develop appropriate software modules that provide a foundation for student interaction with the system. In addition experiments had to be developed and tested to determine if they were appropriate for incorporation into the beginning flight simulation course, AERO-41B. For the most part these goals were accomplished. Experiments were developed and evaluated by graduate students. More work needs to be done in this area. The complexity and length of the experiments must be refined to match the programming experience of the target students. It was determined that few undergraduate students are ready to absorb the full extent and complexity of a real-time flight simulation. For this reason the experiments developed are designed to introduce basic computer architectures suitable for simulation, the programming environment and languages, the concept of math modules, evaluation of acquired data, and an introduction to the meaning of real-time. An overview is included of the system environment as it pertains to the students, an example of a flight simulation experiment performed by the students, and a summary of the executive programming modules created by the students to achieve a user-friendly multi-processor system suitable to an aero engineering educational program.

Source record↗