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Easily made, pen-light battery operated production check gauge has probe-activated switch with fail-safe features to insure proper operation. Parts can be reliably and quickly checked. Gauge is equipped with tolerance band adjustment and can use interchangeable probes for different applications. Accompanying tester permits frequent check of calibration.
Ride quality research to determine criteria to describe vehicle performance characteristics which will insure passenger comfort is discussed. The manner in which disciplines of vehicle environmental dynamics, structural dynamics, and electromechanical measurements are combined to define passenger environments is described. The activities of many governmental and private agencies in the field of passenger comfort are examined.
A full order adaptive observer is described for observing the states of a single-input single-output observable continuous differential system with unknown parameters. Convergence of the observer states to those of the system is accomplished by directly changing the parameters of the observer using an adaptive law based upon Liapunov stability theory. Observer eigenvalues may be freely chosen. Some restriction is placed upon the system input in that it must be sufficiently rich in frequencies in order to insure convergence.
A 0.05-scale model of the NASA-MSC Orbiter 040A Configuration was tested. Test duration was approximately 80 hours during which the model was tested in and out of ground effect with a stationary and moving ground belt. Model height from ground plane surface was varied from one and one-half wing span to landing touchdown while angle of attack varied from -4 to 20 degrees. Eleven effectiveness and alternate configuration geometries were tested to insure complete analysis of low aspect ratio wing aircraft in the presence of ground effect. Test Mach number was approximately 0.067 with a corresponding dynamic pressure value of 6.5 psf.
Experimental and theoretical investigations were undertaken to determine the role of gravity-induced free convection upon the liquefaction dynamics of a cylindrical paraffin slab under normal gravity conditions. The experimental equipment consisted of a test cell, a fluid-loop heating system, and a multipoint recorder. The test chamber was annular in shape with an effective radius of 1.585 cm and a length of 5.08 cm. The heating chamber was a 1.906 cm diameter tube going through the center of the test chamber, and connected to the fluid loop heating system. All experimental runs were made with the longitudinal axis of the test cell in the vertical direction to insure that convection was not a function of the angular axis of the cell. Ten melting runs were made at various hot wall temperatures. Also, two pure conduction solidification runs were made to determine an experimental latent heat of fusion.
A method is presented to investigate the atmospheric energy budget as related to cyclogenesis. Energy budget equations are developed that are shown to be advantageous because the individual terms represent basic physical processes which produce changes in atmospheric energy, and the equations provide a means to study the interaction of the cyclone with the larger scales of motion. The work presented represents an extension of previous studies because all of the terms of the energy budget equations were evaluated throughout the development period of the cyclone. Computations are carried out over a limited atmospheric volume which encompasses the cyclone, and boundary fluxes of energy that were ignored in most previous studies are evaluated. Two examples of cyclogenesis over the eastern United States were chosen for study. One of the cases (1-4 November, 1966) represented an example of vigorous development, while the development in the other case (5-8 December, 1969) was more modest. Objectively analyzed data were used in the evaluation of the energy budget terms in order to minimize computational errors, and an objective analysis scheme is described that insures that all of the resolution contained in the rawinsonde observations is incorporated in the analyses.
Industrial health measures to ensure worker productivity constitute physical examinations as well as environmental control systems. Considered are automatic record keeping facilities for case histories, preventive medical and mental counselling, development of safety standards, and health insurance and disability benefit plans. Cooperation of industry health programs with community health aspects is required to eliminate the loss of manpower capability through alcoholism or mental disease.
This is a preliminary study of possible necessary and sufficient conditions to insure stationarity in the solution process for a stochastic differential equation. It indirectly sheds some light on ergodicity properties and shows that the spectral density is generally inadequate as a statistical measure of the solution. Further work is proceeding on a more general theory which gives necessary and sufficient conditions in a form useful for applications.
The problems inherent in the design and construction of a hydrostatic azimuth thrust bearing for a tracking antenna of very large size were studied. For a load of 48,000,000 lbs., it is concluded that the hydrostatic bearing concept is feasible, provided that a particular multiple pad arrangement, high oil viscosity, and a particular load spreading arrangement are used. Presently available computer programs and techniques are deemed to be adequate for a good portion of the design job but new integrated programs will have to be developed in the area of the computation of the deflections of the supporting bearing structure. Experimental studies might also be indicated to ascertain the life characteristics of grouting under cyclic loading, and the optimization of hydraulic circuits and pipe sizes to insure the long life operation of pumps with high viscosity oil while avoiding cavitation.
A set of requirements is presented to insure the highest practical standard of safety for the Apollo 17 Calibration Facility in terms of identifying all critical or catastrophic type hazard areas. Plans for either counteracting or eliminating these areas are presented. All functional operations in calibrating the ultraviolet spectrometer and the testing of its components are described.
The asymptotic properties of feedback systems are discussed, containing uncertain parameters and subjected to stochastic perturbations. The approach is functional analytic in flavor and thereby avoids the use of Markov techniques and auxiliary Lyapunov functionals characteristic of the existing work in this area. The results are given for the probability distributions of the accessible signals in the system and are proved using the Prohorov theory of the convergence of measures. For general nonlinear systems, a result similar to the small loop-gain theorem of deterministic stability theory is given. Boundedness is a property of the induced distributions of the signals and not the usual notion of boundedness in norm. For the special class of feedback systems formed by the cascade of a white noise, a sector nonlinearity and convolution operator conditions are given to insure the total boundedness of the overall feedback system.
Quality control procedures are established for personnel who are concerned with receiving, storage, transfer, inspection, and use of flight or mission related hardware for the electron/proton spectrometer (EPS) program. While general guidelines, designed to cover all situations, exist, this document provides guidelines and procedures specifically designed to supplement the quality assurance activity on the EPS Program. It is the purpose of this document to insure that all equipment, parts and other hardware received and/or used in the EPS program meet or surpass the standards and requirements established by cognizant authorities.
A centrifugal impeller based on an existing backswept design was defined. In addition, a vaned diffuser was designed to match this impeller and also to be compatible with an existing 6:1 compressor test rig. The mechanical integrity of this design was verified by analysis. Hardware was procured and inspected to insure conformity with design tolerances. An overspeed test was successfully conducted on one of the impellers fabricated under this program.
The author has identified the following significant results. Numerous previously unmapped faults in central Oregon have been distinguished on ERTS-1 imagery. Tectonic mapping of fault-controlled linears demonstrates the utility of ERTS-1 imagery as a mean of illustrating and studying the regional tectonics of the state. Soil colors observed on ERTS-1 frame 1075-18150-5 at the eastern end of the Columbia basin correlate very well with those from descriptions of soils from that area. Digital output from frame 1021-18151 has shown the enhanced ability to interpret such features as joint patterns, shadowed landslide blocks, bottomlands, and drainage patterns. Widespread use of wheat-fallow rotation in northern Umatilla County, Oregon, insures that nearly one-half of the cultivated soil is devoid of vegetation much of the time. On ERTS-1 imagery, fallow fields are only slightly darker than fields of wheat stubble at the western end of the transect. Similar climate-related contrasts in soil color are visible on ERTS-1 Imagery from several other portions of the Columbia Basin. Absence of steep topography in the area mentioned, however, minimizes the disturbing effect caused by shadows.
Safety procedures and devices used to insure superconducting magnetic suspension system reliability are outlined. Power supplies and system failure are included.
The steering system of the space shuttle vehicle is presented for the several hundred miles of flight preceding landing. The guidance scheme is characterized by a spiral turn to dissipate excess potential energy (altitude) prior to a standard straight-in final approach. In addition, the system features pilot oriented control, drag brakes, phugoid damping, and a navigational capacity founded upon an inertial measurement unit and an on-board computer. Analytic formulas are used to calculate, represent, and insure the workability of the system's specifications
The development, manufacture, and testing of an optical steerer intended for use in spaceborne optical radar systems are described. Included are design principles and design modifications made to harden the device against launch and space environments, the quality program and procedures developed to insure consistent product quality throughout the manufacturing phase, and engineering qualification model testing and evaluation. The delivered hardware design is considered conditionally qualified pending action on further recommended design modifications.
The physics of accelerometer applications are reviewed, and details are given on accelerometer instruments and the principles of their operations. The functions to which accelerometers are applied are listed, and terms commonly used in accelerometer reports are defined. Criteria guides state what rule, limitation, or standard must be imposed on each essential design element to insure successful design. Elaboration of these criteria in the form of recommended practices show how to satisfy each of these criteria, with the best procedure described when possible.