Orbit transfer rocket engine technology program: Automated preflight methods concept definition

The possibility of automating preflight engine checkouts on orbit transfer engines is discussed. The minimum requirements in terms of information and processing necessary to assess the engine'e integrity and readiness to perform its mission were first defined. A variety of ways for remotely obtaining that information were generated. The sophistication of these approaches varied from a simple preliminary power up, where the engine is fired up for the first time, to the most advanced approach where the sensor and operational history data system alone indicates engine integrity. The critical issues and benefits of these methods were identified, outlined, and prioritized. The technology readiness of each of these automated preflight methods were then rated on a NASA Office of Exploration scale used for comparing technology options for future mission choices. Finally, estimates were made of the remaining cost to advance the technology for each method to a level where the system validation models have been demonstrated in a simulated environment

Electron Self Energy for Higher Excited S Levels

A nonperturbative numerical evaluation of the one-photon electron self energy for the 3S and 4S states with charge numbers Z=1 to 5 is described. The numerical results are in agreement with known terms in the expansion of the self energy in powers of Zalpha.Comment: 3 pages, RevTeX, to appear in Phys. Rev.

Hypersonic test facility Patent

Hypersonic test facility for studying ablation in models under high pressure and high temperatur

Investigation of relationships between linears, total and hazy areas, and petroleum production in the Williston Basin: An ERTS approach

The author has identified the following significant results. ERTS-1 imagery in a variety of formats was used to locate linear, tonal, and hazy features and to relate them to areas of hydrocarbon production in the Williston Basin of North Dakota, eastern Montana, and northern South Dakota. Derivative maps of rectilinear, curvilinear, tonal, and hazy features were made using standard laboratory techniques. Mapping of rectilinears on both bands 5 and 7 over the entire region indicated the presence of a northeast-southwest and a northwest-southeast regional trend which is indicative of the bedrock fracture pattern in the basin. Curved lines generally bound areas of unique tone, maps of tonal patterns repeat many of the boundaries seen on curvilinear maps. Tones were best analyzed on spring and fall imagery in the Williston Basin. It is postulated that hazy areas are caused by atmospheric phenomena. The ability to use ERTS imagery as an exploration tool was examined where petroleum and gas are presently produced (Bottineau Field, Nesson and Antelope anticlines, Redwing Creek, and Cedar Creek anticline). It is determined that some tonal and linear features coincide with location of present production in Redwing and Cedar Creeks. In the remaining cases, targets could not be sufficiently well defined to justify this method

Thematic Mapper Agricultural Applications Performance -- Speculations and Implications for Research

We discuss how performance of the technology used in agricultural applications such as satellite-aided production forecasting as was done in the Large Area Crop Inventory Experiment (LACIE) is expected to be improved when using Thematic Mapper (TM) data as opposed to Landsat Multispectral Scanner (MSS) data. We place this discussion in the context of eight characteristics of the TM: (1) Spectral band placement and width, (2) spacial resolution, ( 3 ) temporal registration accuracy, (4) radiometric sensitivity, (5) temporal sampling frequency, (6) scan angle, (7) data timeliness, and (8) data volume. The TM specifications clearly alleviate many of the deficiencies of the MSS; experience with similar aircraft scanner data shows that the TM will lead to substantial improvements in our ability to recognize or characterize the elements of agricultural scene. The major research issues associated with the TM are then: How useful is TM data for applications? How much better is TM data than MSS data for applications? What is the relative importance of various TM features in the improvements? How should existing analysis procedures be modified to best use TM data? Does the extra information brought by TM increase the range of applicability of a crop or vegetation signature? One of the major lessons of LACIE was that, given the great diversity of agricultural conditions, quantitative procedural comparisons are extremely difficult. This is true both because of the high variance introduced by the diversity of the problem and because certain procedures (or features) have benefits only under specific conditions. We believe that an objective, representative evaluation of the TM in agriculture will require a carefully designed series of extensive experiments using state-of-the-art procedures, rather than the sort of exploratory investigations conducted in the ERTS and ERTS follow-on investigations. A portion of this evaluation will be conducted within the Agriculture and Resources Inventory Surveys Through Aerospace Remote Sensing (AGRISTARS) program to be conducted jointly by the U. S. Department of agriculture, the National Aeronautics and Space Administration, the U. S. Department of Commerce (NCAA), the Department of Interior, and the Agency for International Development - we will outline the types of investigations to be done - but it is clear that a full evaluation includes detailed comparative evaluations and will require the involvement of many institutions. The challenge now facing primarily the research institutions, but also NASA, is to devise an approach including the use of state-of-the art technology whereby the efforts of many investigators can be combined to: Identify the experiments to be done which focus on critical applications technology issues (such as separation of wheat and barley, small fields, etc.) Acquire the data, including ground truth. Conduct the data processing. Analyse the results. Perhaps some approaches used in LACIE could be helpful here

Preschool as a Wellspring for Democracy: Endorsing Traits of Reasonableness in Early Childhood Education

Traits of reasonableness are necessary characteristics of successfully engaged citizens within pluralistic liberal democratic societies. Given the evident unlikelihood of the spontaneous development of these critical characteristics, pedagogical effort ought to be exerted towards ensuring that this goal is realized. In what follows, we argue that preschool presents a unique and compelling opportunity for supporting this worthy pedagogical aim, such that, despite purported prohibitions entailed within arguments for the political neutrality of curricula, it ought to be promoted within this area. In the service of illustrating this point, we provide four examples of promising beginnings for this work

Research in satellite-aided crop inventory and monitoring

Automated information extraction procedures for analysis of multitemporal LANDSAT data in non-U.S. crop inventory and monitoring are reviewed. Experiments to develope and evaluate crop area estimation technologies for spring small grains, summer crops, corn, and soybeans are discussed

Evaluation of insulation materials and composites for use in a nuclear radiation environment, phase 2

The nuclear heating of the propellant in all of the four baseline RNS configurations studied was much lower than that of the nuclear flight module configuration with the 5000-MW NERVA analyzed previously. Although the nuclear heating has been reduced, the effect of nuclear heating on the propellant as well as the effect of nuclear heating on internal structures such as antivortex baffles, screens, and sump components cannot be neglected. In addition, it was found that the present analytical precedures were not able to predict boundary layer initiation and breakoff points with the accuracy necessary to predict propellant thermodynamic nonequilibrium (stratification) and/or mixing

Investigation of relationships between linears, tonal and hazy anomalies, and petroleum production in the Williston Basin: An ERTS approach

There are no author-identified significant results in this report

Constraining the Temperature of Impact Melt from the Mistastin Lake Impact Structure Using Zircon Crystal Structures

Impact melt is a product of hyper-velocity impact events formed by the instantaneous melting of near-surface target rocks. Constraining the temperature of impact melt is vital to understanding its prograde heating and cooling history, which can have implications for inferring the environment of early Earth ~4.0 billion years ago when microbial life potentially arose. To date, only one datum on the initial impact melt temperature has been derived by Timms et al. These authors studied zirconia microstructures and crystallographic orientations that revealed the former presence of cubic zirconia, found in a black impact glass at the Mistastin Lake impact structure, Canada. The presence of cubic zirconia indicates a minimum temperature for the impact melt of >2370C from the dissociation temperature of zircon to cubic zirconia and liquid SiO2. With only one temperature datum, it is still difficult to constrain the entire temperature range experienced during the impact melting process; from its instantaneous formation to thermal equilibrium with the cold clasts collected along the crater floor and walls. In addition, obtaining a temperature value from only one type of impactite limits the inferred temperature range, because each impactite experiences a different cooling history. In this study, we present a preliminary investigation of 61 zircon crystals, 14 of which are similar to those studied by Timms et al., from the Mistastin Lake impact structure. To acquire a more accurate temperature profile representative of impact melt, zircon crystals were collected from different types of impactites containing impact melt, including additional samples of the black impact glass studied by Timms et al