Electrical-power-system data base for consumables analysis. Volume 1: Electrical equipment list, activity blocks, and time lines

A standardized data base is described which consists of a space shuttle electrical equipment list, activity blocks defining electrical equipment utilization, and activity-block time lines for specific mission analyses. Information is presented to facilitate utilization of the data base, to provide the basis for the electrical equipment utilization to enable interpretation of analyses based on the data contained herein

Aviation and programmatic analyses; Volume 1, Task 1: Aviation data base development and application

A method was developed for using the NASA aviation data base and computer programs in conjunction with the GE management analysis and projection service to perform simple and complex economic analysis for planning, forecasting, and evaluating OAST programs. Capabilities of the system are discussed along with procedures for making basic data tabulations, updates and entries. The system is applied in an agricultural aviation study in order to assess its value for actual utility in the OAST working environment

Experiments on Chute Flows of Granular Materials

Experiments on continuous, steady flows of granular materials down an inclined channel or chute were made with the object of acquiring information on the rheological properties of the granular material flow and the nature of the boundary condition on the base of the channel. Specifically measurements were made of the mean material velocities and velocity profiles on all boundaries of the flow using cross-correlation of two neighboring fibre-optic displacement probes. The output from these probes was used to obtain (1) the unsteady or random component of the particle velocity in the longitudinal direction and (2) a measure of the volume fraction of the flow in contact with the base by counting the frequency of passage of the particles. Measurement was also made of the depth of the flow, the mass flow rate and the shear stress on the base. The latter employed a strain-gauged shear force plate built into the base. The experiments are currently in progress and so further data will be presented at a later date. Nevertheless the preliminary data have yielded a number of interesting features

Flight design system-1 system design. Volume 5: Data management and data base documentation support system

Application software intended to reduce the man-hours required per flight design cycle by producing major flight design documents with little or no manual typing is described. The documentation support software is divided into two separately executable processors. However, since both processors support the same overall functions, and most of the software contained in one is also contained in the other, both are collectively presented

Effect of impurities and processing on silicon solar cells. Volume 1: Characterization methods for impurities in silicon and impurity effects data base

Two major topics are treated: methods to measure and evaluate impurity effects in silicon and comprehensive tabulations of data derived during the study. Discussions of deep level spectroscopy, detailed dark I-V measurements, recombination lifetime determination, scanned laser photo-response, conventional solar cell I-V techniques, and descriptions of silicon chemical analysis are presented and discussed. The tabulated data include lists of impurity segregation coefficients, ingot impurity analyses and estimated concentrations, typical deep level impurity spectra, photoconductive and open circuit decay lifetimes for individual metal-doped ingots, and a complete tabulation of the cell I-V characteristics of nearly 200 ingots

On the simulation of infiltration- and saturation-excess runoff using radar-based rainfall estimates: Effects of algorithm uncertainty and pixel aggregation

The effects of uncertainty in radar-estimated precipitation input on simulated runoff generation from a medium-sized (100-km2) basin in northern Texas are investigated. The radar-estimated rainfall was derived from Next Generation Weather Radar (NEXRAD) Level II base reflectivity data and was supplemented by ground-based rain-gauge data. Two types of uncertainty in the precipitation estimates are considered: (1) those arising from the transformation of reflectivity to rainfall rate and (2) those due to the spatial and temporal representation of the 'true' rainfall field. The study explicitly differentiates between the response of simulated saturation-excess runoff and infiltration-excess runoff to these uncertainties. The results indicate that infiltration-excess runoff generation is much more sensitive than saturation-excess runoff generation to both types of precipitation uncertainty. Furthermore, significant reductions in infiltration-excess runoff volume occur when the temporal and spatial resolution of the precipitation input is decreased. A method is developed to relate this storm-dependent reduction in runoff volume to the spatial heterogeneity of the highest-intensity rainfall periods during a storm

PROMIS series. Volume 8: Midlatitude ground magnetograms

This is the eighth in a series of volumes pertaining to the Polar Region Outer Magnetosphere International Study (PROMIS). This volume contains 24 hour stack plots of 1-minute average, H and D component, ground magnetograms for the period March 10 through June 16, 1986. Nine midlatitude ground stations were selected from the UCLA magnetogram data base that was constructed from all available digitized magnetogram stations. The primary purpose of this publication is to allow users to define universal times and onset longitudes of magnetospheric substorms

Astrometric telescope facility. Preliminary systems definition study. Volume 3: Cost estimate

The results of the Astrometric Telescope Facility (ATF) Preliminary System Definition Study conducted in the period between March and September 1986 are described. The main body of the report consists primarily of the charts presented at the study final review which was held at NASA Ames Research Center on July 30 and 31, 1986. The charts have been revised to reflect the results of that review. Explanations for the charts are provided on the adjoining pages where required. Note that charts which have been changed or added since the review are dated 10/1/86; unchanged charts carry the review date 7/30/86. In addition, a narrative summary is presented of the study results and two appendices. The first appendix is a copy of the ATF Characteristics and Requirements Document generated as part of the study. The second appendix shows the inputs to the Space Station Mission Requirements Data Base submitted in May 1986. The report is issued in three volumes. Volume 1 contains an executive summary of the ATF mission, strawman design, and study results. Volume 2 contains the detailed study information. Volume 3 has the ATF cost estimate, and will have limited distribution

Euclidean versus hyperbolic congestion in idealized versus experimental networks

This paper proposes a mathematical justification of the phenomenon of extreme congestion at a very limited number of nodes in very large networks. It is argued that this phenomenon occurs as a combination of the negative curvature property of the network together with minimum length routing. More specifically, it is shown that, in a large n-dimensional hyperbolic ball B of radius R viewed as a roughly similar model of a Gromov hyperbolic network, the proportion of traffic paths transiting through a small ball near the center is independent of the radius R whereas, in a Euclidean ball, the same proportion scales as 1/R^{n-1}. This discrepancy persists for the traffic load, which at the center of the hyperbolic ball scales as the square of the volume, whereas the same traffic load scales as the volume to the power (n+1)/n in the Euclidean ball. This provides a theoretical justification of the experimental exponent discrepancy observed by Narayan and Saniee between traffic loads in Gromov-hyperbolic networks from the Rocketfuel data base and synthetic Euclidean lattice networks. It is further conjectured that for networks that do not enjoy the obvious symmetry of hyperbolic and Euclidean balls, the point of maximum traffic is near the center of mass of the network.Comment: 23 pages, 4 figure

Microfabricated Silicon Mixers for Submillisecond Quench-Flow Analysis

Elucidation of fast chemical reactions such as protein folding requires resolution on a submillisecond time scale. However, most quench-flow and stop-flow techniques only allow chemical processes to be studied after a few milliseconds have elapsed. In order to shorten the minimum observation time for quench-flow experiments, we designed a miniaturized mixer assembly. Two “T” mixers connected by a channel are etched into a 1 cm × 1 cm silicon chip which is interfaced with a commercially available quench-flow instrument. Decreasing the volume of the mixing chambers and the distance between them results in an instrument with greatly reduced dead times. As a test of submillisecond measurements, we studied the basic hydrolysis of phenyl chloroacetate. This reaction proceeds with a second-order rate constant, k = 430 M^(-1) s^(-1), and shows pseudo-first-order kinetics at high hydroxide concentrations. The chemical reaction data demonstrate that the silicon device is capable of initiating and quenching chemical reactions in time intervals as short as 110 μs. The performance of these mixers was further confirmed by visualization using acid-base indicators