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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Universal multiplanar position indicating, rotating boom for mounting various instruments or sensors is described. Boom is telescoping, and apparatus is capable of 3 types of rotation controlled by electric motors. Movement may be continuous or incremental.
Thermocouple implanted in metal mass simulates heat transfer characteristics of connection which is to be soldered. Light signals indicate whether temperature is right, too high, or too low.
The effort expended in developing the following indicators is summarized: (1) event timer; (2) secondary display; and (3) 4 digit display (metabolic). The mechanical design, vibration analysis, and thermal analysis of all these units are identical, and descriptions pertain to all three units. All problems incurred during the program are discussed along with the recommendations, conclusions, and actions taken to rectify the situations.
Techniques of computer calculations used to analyze the potential for improving visual acquisition of collision threats by means of Pilot Warning Indicator systems (PWI) are described. The quantitative effects of PWI resolution and effective range upon the average cumulative probability of detection are presented.
This experiment examined the ability of observers to determine, as quickly as possible, whether a visual indicator was steadily on or flashing. Six flash rates (periods) were combined factorially with three duty cycles (on-off ratios) to define 18 ?types' of intermittent signals. Experimental sessions were divided into six runs of 100 trials, each run utilizing one of the six flash rates. On any given trial in a run, the probability of a steady signal occurring was 0.5 and the probability of a flashing signal occurring was 0.5. A different duty cycle was employed daily for each experimental session. In all, 400 trials were devoted to each of the flash rates at each duty cycle. Accuracy and latency of response were the dependent variables of interest. The results show that the observers view the light for an interval of time appropriate to the expected flash rate and duty cycle; whether they judge the light to be steady or intermittent depends upon whether the light is extinguished during the predetermined waiting period. Adoption of this temporal criterion delays responding in comparison to those tasks involving responses to light onset. The decision or response criteria held by the observers are also sensitive to the parameters of the flashing light: observers become increasingly willing to call a flashing light ?steady' as flash duration increases.
Three pilot warning indicator concepts for collision hazard avoidance are analyzed using computer fast-time simulation. A hazard measure is defined based on a 1/2-g maximum horizontal acceleration, a maximum climb or dive angle of 10 deg for each aircraft, and a 20-sec warning time, through escape completion. The traffic model is based on flight tracks recorded in the Atlanta terminal area over an 11 hr period during August 1967. The basic PWI concept studied alarms on range to flashing beacons mounted on intruder aircraft as a function of relative azimuth and elevation. The alarm-hazard epoch ratio is about 17/1 to maintain the missed-alarm rate below 10%. Beacon vignetting or range-rate discrimination are shown to reduce the false-alarm rate by about 75%.
Demonstration that dye penetrant indications on the heat-affected zone of 2014-T6 aluminum GMA weldments are frequently caused by superficial surface conditions and are less than 0.007 in. deep. The following methods are suggested for minimization of these surface defects: stabilization of the arc, application of dc ?GTA' welding procedures, reduction of the caustic etch time, and use of fine grain materials.
The ratio of intensities of hydrogen Balmer lines H-alpha/H-beta is proposed as an indicator of electron temperature in a nonequilibrium plasma. Although different from the equilibrium case, the intensity ratio is a unique function of electron temperature provided that the optical depth is small for the visible lines and the plasma is far out of equilibrium. For such a plasma, the H-alpha/H-beta intensity ratios are computed. The results are tabulated in the form of a conversion table between the measured excitation temperature and the true electron temperature. The ranges of applicability of the conversion table are also computed and are presented in separate tables. An example is shown in which particle densities are consistent with the Saha equilibrium condition at the apparent excitation temperature even though the plasma is in nonequilibrium at a different true electron temperature.
Weighing device measures loads as a function of its elongation. Device is compact, simple, and inexpensive. It does not require presetting and will measure any load from zero to its yield point. Because of its low cost relative to other load indicators such as strain gauges, device can be used as turnbuckle for tensioning straps, rods, or cables where accurate preloading is critical.
Unit automatically charges batteries to desired state-of-charge levels, monitors functional battery parameter data both on meters and printer, and automatically activates alarm in event of battery malfunctions. Unit consists of state-of-charge indicator panel, control panel, monitor panel, power panel, charging-current power supply, and load panel.
Published report discusses feasibility of ultrasonic techniques; neutron techniques; X-radiography; optical devices; gamma ray devices; and conventional displacement sensors. Use of signal transmitters in place of slip rings indicated possible improvement and will be subject of futher study.
The method of pseudo-resonance cross sections is used to analyze published temperature-dependent neutron transmission and self-indication measurements on tantalum in the unresolved region. In the energy region analyzed, 1825.0 to 2017.0 eV, a direct application of the pseudo-resonance approach using a customary average strength function will not provide effective cross sections which fit the measured cross section behavior. Rather a local value of the strength function is required, and a set of resonances which model the measured behavior of the effective cross sections is derived. This derived set of resonance parameters adequately represents the observed resonance hehavior in this local energy region. Similar analyses for the measurements in other unresolved energy regions are necessary to obtain local resonance parameters for improved reactor calculations. This study suggests that Doppler coefficients calculated by sampling from grand average statistical distributions over the entire unresolved resonance region can be in error, since significant local variations in the statistical distributions are not taken into consideration.
The indicated failures of the inertial coupling unit were investigated. The coupling data unit assembly failure detection circuits and the diagnostic tests are described. It is concluded that conductive contamination in a zener diode in the failure-detect circuit of the coupling data unit assembly most likely caused the problem.
Device facilitates pilot control of g-load maneuvers and provides immediate indication of g-load constraint violations. It may be used in test flights, in aircraft simulators, or in displays of performance of remotely piloted aircraft.
Neutron transmission and self-indication ratio measurements have been carried out at the RPI LINAC on depleted U up to 100 KeV in order to investigate the temperature dependence of resonance self-shielding. These measurements were performed at three sample temperatures (77 deg k, 295 deg k, and 973 deg k) and with sample thicknesses ranging from 0.0076 to 0.0621 atom/barn. Both stochastic sampling and analytical methods have been used to interpret these data. Average resonance parameters have been obtained and temperature dependence as well as sample thickness dependence of the data have been extensively studied.
The author has identified the following significant results. Land use change, water quality, and air quality indices have been calculated from analysis of ERTS-1 multispectral scanning imagery and computer compatible tapes. Specifications have been developed and discussed for an ERTS-1 environmental monitoring system which help to serve the information needs of environmental managers at the Federal, state, regional, and local level. General conclusions of the investigation are that ERTS-1 data is very useful in land use mapping and updating to 10-15 categories, and can provide an overall measure of air and water turbidity; however, more and better ground truth and possibly additional spacecraft sensors will be required if specific air and water pollutants are to be quantified from satellite data.
Data are presented on the use of the method of magnetobiological indication for defining the immunobiological state of patients with very serious diseases. It has been found that the enzymes of a patient react more sensitively to the energy from a magnetic field. It is important that the magnetoreactivity of the enzymes, like the cell forms of the blood in the patients, have a certain relationship to the clinical-nosological forms and the dynamics of the illness of the subject.
It is shown that the daily quick look solar wind velocities based on the Ames Research Center solar wind plasma data obtained on the Pioneer spacecraft are surprisingly reliable indicators of interplanetary activity. These velocities can appropriately be used in correlation studies with an average accuracy of plus or minus 5%. This accuracy reflects the 'jitter' in the solar wind velocity during quiescent intervals and across high-speed streams.