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Desensitizing microcircuits to variations in temperature and production spread - tolerance in performance criteria due to production spread of parameters
A description is presented of a strategy for analyzing the combustion process and the degradation products which are formed. One of three primary objectives in the study of polymer degradation is related to the characterization of the material to be studied and the investigation of the thermal behavior of the material. Another objective is concerned with the definition of the nature of the decomposition process by identification and quantitation of the degradation products. The third objective involves the determination of the mechanism and kinetics of the decomposition process. The methods of sample degradation include pyrolysis, oxidative degradation, flaming combustion, and the use of large-scale combustion chambers. Methods of chemical separation and identification are considered, taking into account low-boiling volatiles, high-boiling volatiles, and ancillary techniques.
The feasibility of commercial manufacturing of pharmaceuticals in space is analyzed and the study results are presented. The chronology of the study process is discussed. The separation of serum proteins by the continuous flow electrophoresis process is investigated. The production requirements of twelve candidate products including antihemophilic factor, beta cells, erythropoietin, epidermal growth factor, alpha-1-antitrypsin, and interferon are evaluated.
The semiempirical photometric theory of cometary gas and dust production is recalibrated using UV observations from 14 comets and uniform visual photometry from 8 comets. The calibration is not changed significantly but becomes more secure. The complete theory is presented with all approximations evaluated and explained. Numerical calibration aspects are presented in tables. The theory is applied to P/Halley using a light curve without the artifact caused by the close approach to Earth in 1910. Gas production rates predicted for the 1985/86 apparition are similar to those for 1910.
Techniques for improving the productivity of white-collar workers while maintaining high product quality are examined in reviews and reports. The emphasis is on the application of strategies developed in the private sector to government-agency and aerospace-industry operations. Topics discussed include international competition, organizational attitudes and orientation, management practices, education and training, renewing large organizations, encouraging innovation, national initiatives, employee involvement, management involvement, and applications of new technology.
The findings are reported of the Jet Propulsion Laboratory (JPL)/Software Product Assurance (SPA) Metrics Study, conducted as part of a larger JPL effort to improve software quality and productivity. Until recently, no comprehensive data had been assembled on how JPL manages and develops software-intensive systems. The first objective was to collect data on software development from as many projects and for as many years as possible. Results from five projects are discussed. These results reflect 15 years of JPL software development, representing over 100 data points (systems and subsystems), over a third of a billion dollars, over four million lines of code and 28,000 person months. Analysis of this data provides a benchmark for gauging the effectiveness of past, present and future software development work. In addition, the study is meant to encourage projects to record existing metrics data and to gather future data. The SPA long term goal is to integrate the collection of historical data and ongoing project data with future project estimations.
A study focusing on oxygen production using resources indigenous to Mars is presented. A bank of solid zirconia electrolytic cells that will electrochemically separate oxygen from a high temperature stream of carbon dioxide is at the center of the oxygen production system. The experimental data are discussed with attention given to the cell operating temperature, the carbon dioxide flow rate, and the voltage applied across the cell.
The evolution of software assurance is discussed. The definition and implementation of standards are considered. It is recommended that requirements be clarified at the start of a project. The need for quality assurance in hardware is identified as the coming trend in the production of high cost single units which call for eradication of all errors during the early stages of development. The need to apply quality assurance throughout the whole mission is stressed. The dangers of overpricing product assurance services is stressed.
A reflectance model developed to estimate chlorophyll a concentrations in the presence of marine colored dissolved organic matter, pheopigments, detritus, and bacteria is presented. Nomograms and lookup tables are generated to describe the effects of different mixtures of chlorophyll a and these degradation products on the R(412):R(443) and R(443):R(565) remote-sensing reflectance or irradiance reflectance ratios. These are used to simulate the accuracy of potential ocean color satellite algorithms, assuming that atmospheric effects have been removed. For the California Current upwelling and offshore regions, with chlorophyll a not greater than 1.3 mg/cu m, the average error for chlorophyll a retrievals derived from irradiance reflectance data for degradation product-rich areas was reduced from +/-61 percent to +/-23 percent by application of an algorithm using two reflectance ratios rather than the commonly used algorithm applying a single reflectance ratio.
Volume 3 assists Earth Observing System (EOS) investigators in locating required non-EOS data products by identifying their non-EOS input requirements and providing the information on data sets available at various Distributed Active Archive Centers (DAAC's), including those from Pathfinder Activities and Earth Probes. Volume 3 is intended to complement, not to duplicate, the the EOSDIS Science Data Plan (SDP) by providing detailed data set information which was not presented in the SDP. Section 9 of this volume discusses the algorithm summary tables containing information on retrieval algorithms, expected outputs and required input data. Section 10 describes the non-EOS input requirements of instrument teams and IDS investigators. Also described are the current and future data holdings of the original seven DAACS and data products planned from the future missions and projects including Earth Probes and Pathfinder Activities. Section 11 describes source of information used in compiling data set information presented in this volume. A list of data set attributes used to describe various data sets is presented in section 12 along with their descriptions. Finally, Section 13 presents the SPSO's future plan to improve this report .
Spectral land surface albedo is an important parameter for describing the radiative properties of the Earth. Accordingly it reflects the consequences of natural and human interactions, such as anthropogenic, meteorological, and phenological effects, on global and local climatological trends. Consequently, albedos are integral parts in a variety of research areas, such as general circulation models (GCMs), energy balance studies, modeling of land use and land use change, and biophysical, oceanographic, and meteorological studies. The availability of global albedo data over a large range of spectral channels and at high spatial resolution has dramatically improved with the launch of the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument aboard NASA s Earth Observing System (EOS) Terra spacecraft in December 1999. However, lack of spatial and temporal coverage due to cloud and snow effects can preclude utilization of official products in production and research studies. We report on a technique used to fill incomplete MOD43 albedo data sets with the intention of providing complete value-added maps. The technique is influenced by the phenological concept that within a certain area, a pixel s ecosystem class should exhibit similar growth cycle events over the same time period. The shape of an area s phenological temporal curve can be imposed upon existing pixel-level data to fill missing temporal points. The methodology will be reviewed by showcasing 2001 global and regional results of complete albedo and NDVl data sets.
The new code to generate light curves for GRB observed with the XRT on Swift has been distributed with the latest software release. The code has been extensively tested compared with similar output from Penn State. Adjustments in both codes were made to best represent the latest calibration information and the latest software algorithms. In this talk will be highlighted the steps taken to produce the GRB light-curves, how it is been tested for non GRB sources and last the future adjustments to be made to include a better correction for the bad columns. In addition it will be presented as a new routine developed to automatically collect spectra at different phases of the GRB decay. This new routine will be included in the next software release. The XRT pipeline at GSFC will implement the production of the data files containing the level 3 products. The talk will discuss the current status and the additional data files planned.
The NASA/GEWEX Surface Radiation Budget (SRB) project has produced a 24.5-year continuous record of global shortwave and longwave radiation fluxes at TOA and the Earth's surface from satellite measurements. The time span of the data is from July 1983 to December 2007, and the spatial resolution is 11 latitude11 longitude. The inputs of the latest version (Release 3.0) include the GEOS Version 4.0.3 meteorological information and cloud properties derived from ISCCP DX data. The SRB products are available on 3-hourly, 3-hourly-monthly, daily and monthly time scales. To assess the quality of the product, we extensively validated the SRB data against 5969 site-months of groundbased measurements from 52 Baseline Surface Radiation Network (BSRN) stations. This paper describes first the characteristics of the BSRN data and the GEWEX SRB data, the methodology for quality control and processing of the shortwave BSRN data, and then the systematic SRB-BSRN comparisons. It is found that, except for occasional extreme outliers as seen in scatter plots, the satellite-based surface radiation data generally agree very well with BSRN measurements. Specifically, the bias/RMS for the daily and monthly mean shortwave fluxes are, respectively, -3.6/35.5 and -5.2/23.3W1 m2 under all-sky conditions.
The advent of geostationary satellites, starting with GEMS over South Korea, offer the potential for additional insight into urban air quality. In preparation for these satellites, the joint NIER-NASA KORUS-AQ field campaign in 2016 obtained a large dataset for understanding local air quality and the contribution of local emissions to ozone and PM2.5 pollution. Models partitioned NOx primarily into inorganic nitrate (HNO3 + nitrate aerosol) while observations suggest that acyl peroxy nitrates (PNs) should be an important sink. Models tended to produce ozone too efficiently, which may be due to insufficient alkyl/multifunctional nitrate (ANs) production. Models are unable to simulate the transport of NOx away from the urban center and its impact on ozone production downwind.
Production of cosmic gamma rays by annihilation of antimatter
Gamma ray production from cosmic proton-antiproton interactions
The complex Saturn S-2 welding processes and procedures required considerable development and refinement to establish a production capability that could consistently produce aluminum alloy welds within specified requirements. The special processes and techniques are defined that were established for the welding of gore-to-gore and manhole- or closeout-to-gore.
Laboratory-scale screening tests were carried out on coal from Harrison County, Ohio to establish chlorination and hydrodesulfurization conditions for the batch reactor production of chlorinolysis and chlorinolysis-hydrodesulfurized coals. In addition, three bituminous coals, were treated on the lab scale by the chlorinolysis process to provide 39 to 62% desulfurization. Two bituminous coals and one subbituminous coal were then produced in 11 to 15 pound lots as chlorinolysis and hydrodesulfurized coals. The chlorinolysis coals had a desulfurization of 29-69%, reductions in voltatiles and hydrogen. Hydrodesulfurization provided a much greater desulfurization (56-86%), reductions in volatiles and hydrogen. The three coals were combustion tested in the Penn State ""plane flame furnace'' to determine ignition and burning characteristics. All three coals burned well to completion as: raw coals, chlorinolysis processed coals, and hydrodesulfurized coals. The hydrodesulfurized coals experienced greater ignition delays and reduced burning rates than the other coals because of the reduced volatile content. It is thought that the increased open pore volume in the desulfurized-devolatilized coals compensates in part for the decreased volatiles effect on ignition and burning.