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Transfer of dye shows quality of contact between two mating parts. Mating parts checked for fit by spreading fluorescent dye on one, making brief light contact with other, and looking (under UV light) for transferred dye. Dye offers greater visibility under ultraviolet illumination, allowing better indication of how precisely parts match and what areas interfere.
A new instrument capable of computing in real time the per-cycle indicated mean effective pressure (IMEP) of internal combustion engines and compressors was designed and tested. The values of IMEP obtained with the new instrument were found to be in excellent agreement with values obtained by previous postrun data reduction techniques.
A method and apparatus are provided for indicating the altitude at which an aircraft should fly so the W/d ratio (weight of the aircraft divided by the density of air) more closely approaches the optimum W/d for the aircraft. A passive microwave radiometer on the aircraft is directed at different angles with respect to the horizon to determine the air temperature, and therefore the density of the air, at different altitudes. The weight of the aircraft is known. The altitude of the aircraft is changed to fly the aircraft at an altitude at which is W/d ratio more closely approaches the optimum W/d ratio for that aircraft.
Aircraft control-position indicator cockpit-mounted instrument that displays positions of elevator and ailerons to pilot. Display is cruciform array of lights: horizontal row of amber lights and vertical row of green lights representing aileron and elevator positions, respectively. Display used extensively in spin testing and has been trouble-free, with no maintenance required after about 30 hours of operation.
Indicator for valves or other control mechanisms easy to mount, reliable, and explosion proof. Replaces slidewires expensive and difficult to mount. Used in hazardous areas that require nonexplosive electrical contacts, and controlling highly flammable fuels. Readily adapted to oil-refining and other chemical processing plants.
Linear variable differential transformer (LVDT) incorporated within cylinder of hydraulic actuator gives precise readout of position of piston relative to cylinder. LVDT contained completely within actuator. System requires precise positioning and position readout for computer control of model motions. Minimal space available for motion cylinders, and precise, continuous position readout (with no steps or pulses) required. Device provides continuous and accurate position indication of a hydraulic cylinder by means of integral, coaxially mounted LVDT.
A battery charge/state of charge indicator (BC/SCI) system for electric vehicle use was developed. The original and subsequent objectives for the BC/SCI and the rationale for those objectives are described. The requirements generated from the objectives are listed and a description of the BC/SCI is provided. The power section problem, the tests, and the test results are discussed.
An indicating device designed to provide an electrical signal relative to the position of a load is described. The device has a central housing with two wing structures on each side which support conventional switch means having cantilevered arms. Extending through the housing is a movable shaft that is spring biased to a forward extended position and adapted to respond against a load being positioned. The rear end of the movable shaft has an adjustable cam means which acts upon the cantilevered ams to cause a switching action upon shifting of the movable shaft by a load.
Circuit produces PPI display on conventional X-Y oscilloscope. Circuit requires three inputs. First is once-per-scan pulse to synchronize display to north, relative heading, or another reference direction. Second is once-per-degree-of-rotation pulse to advance sweep rotation. Third input is normal sweep ramp. Duration of ramp corresponds to maximum displayed range. Changing ramp duration, while holding its peak amplitude constant, changes maximum displayed range. Conventional methods to accomplish this task use mechanically-driven deflection coils or mechanically-driven sine and cosine potentiometers, requiring mechanical preventive maintenance plus dedicated display indicator. New method displays radar sweep on any conventional storage oscilloscope.
Measurements of stable and radioactive spallation products in meteorites allow to investigate their histories, especially with respect to the exposure to galactic cosmic ray particles and the pre-atmospheric size of the object. While the concentrations of spallation products lead to the determination of exposure and terrestrial ages, production rate ratios are characteristic for the location of the sample in the meteorite. So, one of the aims of this investigation on meteorites is to obtain depth indicators from suitable pairs of cosmogenic nuclides. Because of the different depth profiles for nuclide productions it is necessary to determine the concentrations of a larger number of spallation products in aliquots of a single small sample. Such same sample measurements of Be-10 and light noble gases were performed on 15 ordinary chondrites (7 H- and 8 L-chondrites. Be-10 was determined by accelerator mass spectrometry and the noble gases were measured by static mass spectrometry. The results are summarized and discussed.
Many previous studies of both behavioral and physiological correlates of cognitive workload have burdened subjects with a contrived secondary task in order to assess the workload of a primary task. The present study investigated event-related potential (ERP) indices of workload in a single task paradigm. Subjects monitored changing digital readouts for values that went 'out-of-bounds'. The amplitude of a long-latency positivity in the ERPs elicited by readout changes increased with the number of readouts being monitored. This effect of workload on ERPs is reported, along with plans for additional analyses to address theoretical implications.
The Kronecker indices of smooth affine-nonlinear control systems presently defined are noted to determine the collection of controllable linear systems that are obtainable on the basis of local feedback equivalences and state-space reductions. Because attention is given to the invariants of systems under equivalences, and the behavior of these invariants under mappings that arise from state submersions, local representations of systems are used wherever possible to render cases more accessible.
Different techniques which can be used to indicate the quality of the mixing ratios retrieved from spectral radiance measurements made by the CLAES instrument for 11 different atmospheric gases are discussed. A key to retrieval from noisy data is the Singular Value Decomposition (SVD), which is described. The use of the SVD with simulated data and radiance measurements from a balloon floating at 30 km is discussed.
Ocular-motor correlates of visual fatigue have remained elusive. Performance of ocular-motor tracking with a wide-band white noise input and the response of the dual-mode, smooth pursuit-saccadic eye movement system as output was used to test visual fatigue. A new visual fatigue indicator, VFI, was defined as the nonlinear remnant after subtracting an identified impulse response contribution to the output. Subjects were required to perform very fatiguing CRT screen reading tasks, and the VFI correlated well with the subjective reports of visual fatigue.
The paper analyzes 28 plasmapause crossings made by the DE1 satellite in the night local time sector (from January to March 1982). Different signatures obtained by the Retarding Ion Mass Spectrometer instrument have been used for this analysis. The observed plasmapause positions (Lpp) have been organized as a function of geomagnetic indices. They are compared with the empirical relationship deduced by Carpenter and Parks (1973) from whistler observations. Moreover, the dependence of Lpp versus Kp has been inferred from model calculations using Kp dependent electric and magnetic fields derived from McIlwain's (1974) E3H electric field model and M2 magnetic field model respectively. Stationary models as well as time dependent ones, have been used to determine the positions of the plasmapause. The results of the model calculations are compared to the observations.
To elucidate the nature of infrared-luminous galaxies discovered with the IRAS satellite, the optical and infrared luminosities of 1161 Markarian galaxies and 2146 'normal' galaxies from the CfA redshift survey are compared. Survival analysis statistical methods that take upper limits fully into account are used. It is found that L(IR)/L(B) is statistically correlated with L(60) in both samples, though they differ in the distribution at low luminosities. The derived correlation shows that L(IR)/L(B) provides an indicator for L(60). Since galaxies selected in unbiased IRAS surveys will have higher L(IR)/L(B) than optically selected galaxies, they are therefore also selected for high L(60).
The infrared absorption spectra of thin crystalline films of sulfur dioxide at 90 K are reported in the 2700 to 450/cm region. The observed multiplicity of the spectral features in the regions of fundamentals is attributed to factor group splittings of the modes in a biaxial crystal lattice and the naturally present minor S-34, S-36, and O-18 isotopic species. Complex refractive indices determined by an iterative Kramers-Kronig analysis of the extinction data, and absolute band strengths derived from them, are also reported in this region.
Factors most important in determining fountain height in Hawaiian-type basaltic eruptions were assessed on the basis of theoretical calculations and observations at Pu'u 'O'o vent, east rift zone of Kilauea, Hawaii. It is shown that fountain height is very sensitive to changes in exsolved gas content (and, thus, can be used to estimate variability in exsolved gas content) and relatively insensitive to large variations in volume flux. Volume flux was found to be the most important parameter determining the equilibrium vent diameter. The results of calculations also indicate that there was a general increase in magma gas content over the first 20 episodes of the Pu'u 'O'o eruption and that gas depletion took place in the conduit beneath the vent during repose periods.