Optimization of structures based on fracture mechanics and reliability criteria
Spacecraft structures weight optimization based on fracture mechanics and reliability cost constraints applied to pressure vessel design
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Spacecraft structures weight optimization based on fracture mechanics and reliability cost constraints applied to pressure vessel design
Optimal reliability of system with nonlinear constraints, using mathematical model and sequential unconstrained minimization technique
NASA reliability program provisions for aeronautical and space system contractors, reviewing evolution process
OAO 2 thermal test reliability analysis, using filtering process to eliminate component and subsystem level failures
Service life testing and reliability estimation, using ordinary and empirical Bayes approach in failure model with gamma probability distribution
Reliability prediction of narrow band structures under random excitations, considering catastrophic and fatigue failure modes
Spacecraft system design with long life reliability for outer planet exploration missions
Reliability in key project decision making, including failure mode/effect analyses, design tradeoff, baseline meetings, hardware storage and data bases
Three phase code transformation task reliability and correlation, representing general/factor analytic intellectual abilities and personality characteristics
NASA NHB reliability engineering provisions for aeronautical and space system contractors, considering criteria for program management, system engineering, manufacturing and facilities.
Modular design techniques improve methods of error detection, diagnosis, and recovery. Theoretical computer (MARCS (Modular Architecture for Reliable Computer Systems)) study deals with postulated and modeled technology indigenous to 1975-1980. Study developments are discussed.
Detector and indicator system, utilizing commercial perforated germanium cryogenic thermometer as level sensor containing adjustable level discriminator with indicators, operates reliably over pressure range from 50 to 900 mm Hg without electronic adjustments.
Failure Modes, Effects, and Criticality Analysis Model disregards failures of insignificant components. Assumptions used to establish baselines for reliability prediction and analytical method are listed. Techniques are applicable to any commercial design and can be extended into software or management systems.
A general form of a comprehensive reliability modeling rationale was formulated for the integrated circuit. Integrated device failure models amenable to long term applications were investigated.
In the proposed modeling approach, when any of the essential key factors are not known initially, they can be approximated in various ways with a known impact on the accuracy of the final predictions. For example, on any program where reliability predictions are started at interim states of project completion, a-priori approximate estimates of the key factors are established for making preliminary predictions. Later these are refined for greater accuracy as subsequent program information of a more definitive nature becomes available. Specific steps to develop, validate and verify these new models are described.
Advanced methods of reliability engineering and quality assurance for aerospace application
Analysis of radio observations of Jupiter were changed to take into account the antenna resolution. A dipole magnetic field with a surface equatorial value of 7 gauss is assumed. The electron temperature is found to increase for r 2.5 Jupiter radii with decreasing r as 1/r cubed, reaching a peak of about 100 MeV at r = 2.5 Jupiter radii. For r 2.5 Jupiter radii, the electron temperature goes as r to the 6th power because of energy lost to radiation. The consequences of making an upper estimate on the proton flux by assuming the magnetic field is loaded with all the energetic protons it can hold are described. The upper limits of proton energy, density, flux, and energy flux are calculated for 1, 2, 2.5, 3, and 6 Jupiter radii. The proton energy and velocity estimates are considered to be fairly reliable; the upper limit to the number density is probably much higher than actuality.
Computer techniques for increasing the stability and reliability of executive and supervisory systems were studied. Program segmentation characteristics are discussed along with a validation system which is designed to retain the natural top down outlook in coding. An analysis of redundancy techniques and roll back procedures is included.