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The gathering of surface potential profiles by computerized processing of electrocardiogram data is projected. These profiles are concerned with the detail of localized potentials on the human body and are obtained by voltages plotted against electrode positions with time as the variable held constant. Sample and hold circuits are considered for processing the multiplexed signal and to digitize and code it for the tape recorder.
Steady state diagnostic testing of an isolated orifice has shown the nature of the interaction between grazing and orifice flow causing the large increase in orifice resistance for both inflow and outflow. A simple inviscid interaction model is developed which uses thin aerofoil theory to account for pressure forces exerted at the interface between the orifice and grazing flow together with a one-dimensional discharge coefficient concept. The effect of grazing flow boundary layer thickness is also included in the model. Resistance measurements for each orifice tested, over a wide range of grazing flow speeds and flow rates, collapse into a single curve when plotted in terms of effective discharge coefficient against orifice to grazing velocity ratio. The correlation curves for inflow and outflow are different. Data for clustered orifices collapse in the same way as those for the single orifice. The effect of boundary layer thickness is compared with model predictions.
The B01 version of the United Subsonic Supersonic Aerodynamic Analysis program is the result of numerous modifications and additions made to the B00 version. These modifications and additions affect the program input, its computational options, the code readability, and the overlay structure. The following are described: (1) the revised input; (2) the plotting overlay programs which were also modified, and their associated subroutines, (3) the auxillary files used by the program, the revised output data; and (4) the program overlay structure.
The curved flow capability of a stability wind tunnel was used to investigate the lateral directional characteristics of an F-18 aircraft. The model is described and the procedures used to obtain and correct the data and a graphical presentation of the results are presented. The results include graphs of lateral directional derivatives versus sideslip or static plots, the lateral directional static stability derivatives versus angle of attack, and finally the lateral directional derivatives versus nondimensional yaw rate for different angles of attack and sideslip. Results are presented for several configurations including complete, complete without vertical tails, complete without horizontal tails, fuselage wing and fuselage alone. Each of these were tested with and without wing leading edge extensions.
It is pointed out that the type 3 (unequilibrated) ordinary chondrites provide a major source of information on the early solar system. However, the interpretation of the data is difficult because all but a few display signs of metamorphic alteration. The present investigation is concerned with the thermoluminescence (TL) sensitivity measurements on 58 chondrules separated from the Dhajala meteorites. The data were discussed briefly by Sparks and Sears (1982). In the current investigation particular attention is given to the constraints placed by these data on the mechanism by which metamorphism is related to TL sensitivity. Dhajala-normalized TL sensitivity of the separated chondrules is plotted against chondrule mass, and a histogram of the CaO contents of 15 chondrules is presented. Histograms showing the TL sensitivity of chondrules separated from the Dhajala meteorite are also provided.
Since the development of the last CIRA in 1972, the number of radars providing winds in the upper middle atmosphere has increased significantly. These systems fill the data gap between 60 km and 110 km. The radars include medium frequency (MF) radars or partial reflection systems giving data from 60/70 to 100/110 km; meteor radars, 80 to 110 km, and M.S.T. radars operating as meteor radars. Data from 12 locations are shown, which represent a good Northern Hemispheric (NH) North American chain, an Oceanian chain which is mainly in the Southern Hemisphere (SH), and some Western Europe data. Generally tidal oscillations have been removed from days or groups of days, and the remaining mean winds and longer period oscillations plotted as height-time contours. Composite cross sections from the years 1978 to 1982 were formed where possible so that only the major temporal features remain.
A capability is proposed that makes it feasible to apply to measured flow field data the visualization tools developed to display numerical solutions for computational fluid dynamic problems. The measurement monitor surface (MMS) methodology was used for the analysis of flow field measurements within a low-aspect-ratio transonic axial-flow fan rotor acquired with two-dimensional laser anemometry. It is shown that the MMS method may be utilized to generate input for the multidimensional processing and analytical tools developed for numerical flow field simulation data. Thus an experimenter utilizing an interactive graphics program could illustrate scalar quantities such as Mach number by profiles, contour lines, carpet plots, and surfaces employing various color intensities. Also, flow directionality can be shown by the display of vector fields and particle traces.
Results are reported of extensive and systematic measurements of hydrogen broadening of the ammonia (0,1,0,0)-(0,0,0,0) band at 200 K. The measured linewidths for each of the observed branches in this band were determined with an average rms of 5 percent or less. Plots of the K manifolds for four of the five branches that were measured are presented. It is suggested that these width data can be used for analyzing atmospheric spectra of the outer planets and for validating theories of foreign-gas broadening of ammonia.
High-resolution absorption measurements of the interstellar Ca II K line observed toward 46 early-type stars in the local ISM (LISM) are presented. Ca II was detected in 36 of the 46 stars with 82 individual cloud components identified. Ca II was detected to most of the stars closer than 50 pc, except in the region of the Galactic quadrant l = 180-270 degrees which also contains the empty line of sight to B CMa at 220 pc. The mean local standard of rest velocity of the 82 Ca II components implies that the LISM clouds are associated with the motion of the solar neighborhood and not the sun. If the present data are combined with other nearby Ca II component velocities taken from the literature, then a cloud centered approximately at l = 90 deg, b = -40 deg moving coherently with the local interstellar wind vector is supported at a significance level of 99 percent. The Ca II data have been combined with Na I data for the same stars to produce a N(Na I)/N(Ca II) ratio for each identified absorption feature. This ratio plotted against the local standard of rest velocities of the clouds shows that the Routly-Spitzer effect exists down to +/- 10 km/s, which supports grain desorption/destruction models that are efficient at returning calcium to the gas phase at these low velocities.
Results are reported on 26 high-resolution (16-51 steps) Ar-40/Ar-39 age spectra obtained on 12 Apollo-15 melt rocks of different composition using a continuous laser system on submg fragments of recrystallized melt and single-crystal plagioclase clasts from impact melt rocks collected at the Apennine Front where the Imbrium and Serenitatis basins intersect. A table is presented with the summary of the Ar-40/Ar-39 spectrum data, which represent 891 individual temperature step analyses. Also presented are 20 of the 26 age spectra along with their respective K/Ca plots. Melt rock fragments and plagioclase clasts from seven of the 12 samples analyzed yielded reproducible, intermediate-T Ar-40/Ar-39 age spectrum plateaus, which were interpreted as crystallization ages that represent the times of impact of bolides onto the lunar surface.
This slide presentation reviews the development of the Plots, Calculations and Graphics Tools (PCG2) system. PCG2 is an easy to use tool that provides a single user interface to view data in a pictorial, tabular or graphical format. It allows the user to view the same display and data in the Control Room, engineering office area, or remote sites. PCG2 supports extensive and regular engineering needs that are both planned and unplanned and it supports the ability to compare, contrast and perform ad hoc data mining over the entire domain of a program's test data.
We present WISE (Wide-field Infrared Survey Explorer) mid-infrared photometry of young stellar object candidates in the Canis Majoris clouds at a distance of 1 kpc. WISE has identified 682 objects with apparent 12 and 22 micron excess emission in a 7 deg x 10 deg field around the CMa Rl cloud . While a substantial fraction of these candidates are likely galaxies, AGB stars, and artifacts from confusion along the galactic plane, others are part of a spectacular cluster of YSOs imaged by WISE along a dark filament in the R1 cloud. Palomar Double Spectrograph observations of several sources in this cluster confirm their identity as young A and B stars with strong emission lines. In this contribution, we plot the optical -mid-infrared spectral energy distribution for the WISE YSO candidates and discuss potential contaminants to the sample . The data demonstrate the utility of WISE in performing wide-area surveys for young stellar objects.
The steady state, nearly sinusoidal behavior of the components in a Free Piston Stirling Engine allows for visualization of the forces in the system using phasor diagrams. Based on Newton's second law, F=ma, any phasor diagrams modeling a given component in a system should close if all of the acting forces have been considered. Since the Advanced Stirling Radioisotope Generator (ASRG), currently being developed for future NASA deep space missions, is made up of such nearly sinusoidally oscillating components, its phasor diagrams would also be expected to close. A graphical user interface (GUI) has been written in MATLAB by taking user input data, passing it to Sage, a 1-D thermodynamic modeling program used to model the Stirling convertor, running Sage and then automatically plotting the phasor diagrams. Using this software tool, the effect of varying different Sage inputs on the phasor diagrams was determined. The parameters varied were piston amplitude, hot end temperature, cold end temperature, operating frequency, and displacer spring constant. By using these phasor diagrams, better insight can be gained as to why the convertor operates the way that it does.
Advanced Air Mobility (AAM), Urban Air Mobility (UAM), and Unmanned Aerial Systems (UAS) vehicles will fly in similar airspace to Transport Category Rotorcraft, thereby requiring them to meet the most severe requirements for HighIntensity Radiated Fields (HIRF) certification. The environment is severe for rotorcraft, much more so than for fixed-wing aircraft, due to lower altitude operations, potentially exposing the vehicles to close and direct view of high-power transmitters on the ground. High-level HIRF exposure potentially leads to avionic system upsets, interference, and undesirable effects. Shielding and circuit protection against HIRF will be a significant barrier to size, weight, and cost, especially for emerging electric vertical take-off and landing (eVTOL) and electric short take-off and landing (eSTOL) vehicles. This paper proposes a novel approach to HIRF protection, which reduces costs by testing and certifying vehicles to a “vehicle tolerance level” that is lower than required for Transport Category Rotorcraft. The remaining protection is achieved by maintaining a safe distance from known HIRF sources, calculated based on the vehicle's tolerance level and transmitter characteristics such as transmit power, antenna beamwidth, and direction. Tailored maps are developed, identifying transmitters and avoidance zones within an operating area or along a flight path, allowing for restricted vehicle operations. The HIRF avoidance zones could be smaller for vehicles with higher tolerance levels, enabling them to operate closer to transmitters. Transmitter data can be extracted from regulatory databases like the FCC and NOAA. A map tool is developed in Matlab to calculate and plot HIRF avoidance zones from transmitters in FCC and NOAA databases as proof of concept. Illustrations are presented for AM/FM/TV transmitters, communication satellite dishes, and weather radars. Also illustrated are HIRF zones for smaller transmitters, including land-mobile radios, pagers, microwave links, and cellular towers. An example of flight planning around the transmitters is presented. This method is a substantial deviation from the standard approach and involves slightly higher flight-planning complexity, but the potential cost savings are significant. Future AAM/UAM/UAS aeronautical charts could include these new HIRF avoidance zones.
Advanced Air Mobility (AAM), Urban Air Mobility (UAM), and Unmanned Aerial Systems (UAS) vehicles will fly in similar airspace to Transport Category Rotorcraft, thereby requiring them to meet the most severe requirements for High Intensity Radiated Fields (HIRF) certification. The environment is severe for rotorcraft, much more so than for fixed-wing aircraft, due to lower altitude operations, potentially exposing the vehicles to close and direct view of high-power transmitters on the ground. High-level HIRF exposure potentially leads to avionic system upsets, interference, and undesirable effects. Shielding and circuit protection against HIRF will be a significant barrier to size, weight, and cost, especially for emerging electric vertical take-off and landing (eVTOL) and electric short take-off and landing (eSTOL) vehicles. This paper proposes a novel approach to HIRF protection, which reduces costs by testing and certifying vehicles to a “vehicle tolerance level” that is lower than required for Transport Category Rotorcraft. The remaining protection is achieved by maintaining a safe distance from known HIRF sources, calculated based on the vehicle's tolerance level and transmitter characteristics such as transmit power, antenna beamwidth, and direction. Tailored maps are developed, identifying transmitters and avoidance zones within an operating area or along a flight path, allowing for restricted vehicle operations. The HIRF avoidance zones could be smaller for vehicles with higher tolerance levels, enabling them to operate closer to transmitters. Transmitter data can be extracted from regulatory databases like the FCC and NOAA. A map tool is developed in Matlab to calculate and plot HIRF avoidance zones from transmitters in FCC and NOAA databases as proof of concept. Illustrations are presented for AM/FM/TV transmitters, communication satellite dishes, and weather radars. Also illustrated are HIRF zones for smaller transmitters, including land-mobile radios, pagers, microwave links, and cellular towers. An example of flight planning around the transmitters is presented. This method is a substantial deviation from the standard approach and involves slightly higher flight-planning complexity, but the potential cost savings are significant. Future AAM/UAM/UAS aeronautical charts could include these new HIRF avoidance zones.
Preliminary results of one phase of a control-motion study program are presented in the form of plots of load factor.and angular acceleration against indicated airspeed and of time histories of several measured quantities. The results were obtained from 197 maneuvers performed by an F-86A jet-fighter airplane during normal squadron operational training. Most of the tactical maneuver8 of which the F-86A is capable were performed at pressure altitudes ranging from 0 to 32,000 feet and at indicated airspeeds ranging from 95 to 650 miles per hour.
The Hopkins Ultraviolet Telescope (HUT) was a 0.9 m telescope and moderate-resolution (Delta)lambda equals 3 A) far-ultraviolet (820-1850 Å) spectrograph that flew twice on the space shuttle, in 1990 December (Astro-1, STS-35) and 1995 March (Astro-2, STS-67). The resulting spectra were originally archived in a nonstandard format that lacked important descriptive metadata. To increase their utility, we have modified the original datareduction software to produce a new and more user-friendly data product, a time-tagged photon list similar in format to the Intermediate Data Files (IDFs) produced by the Far Ultraviolet Spectroscopic Explorer calibration pipeline. We have transferred all relevant pointing and instrument-status information from locally-archived science and engineering databases into new FITS header keywords for each data set. Using this new pipeline, we have reprocessed the entire HUT archive from both missions, producing a new set of calibrated spectral products in a modern FITS format that is fully compliant with Virtual Observatory requirements. For each exposure, we have generated quicklook plots of the fully-calibrated spectrum and associated pointing history information. Finally, we have retrieved from our archives HUT TV guider images, which provide information on aperture positioning relative to guide stars, and converted them into FITS-format image files. All of these new data products are available in the new HUT section of the Mikulski Archive for Space Telescopes (MAST), along with historical and reference documents from both missions. In this article, we document the improved data-processing steps applied to the data and show examples of the new data products.
The properties of nano-crystalline materials are critically dependent on the structure of the constituent grains. Experimental conditions necessary to perform structural analysis of nanocrystalline materials as a two-phase core-surface shell system are discussed. It is shown, that a standard X-ray diffraction measurements and analysis are insufficient and may lead to incorrect conclusions as to the real structure of the materials. A new method of evaluation of powder diffraction data based on the analysis of the shift of the Bragg reflections from their perfect-lattice positions was developed. "Apparent lattice parameters" quantity, alp, was introduced and calculated from the actual positions of each individual Bragg reflection. The alp values plotted versus diffraction vector (Q) show characteristic features that are used for evaluation of the experimental results. The study was based on modeling of nano-grains and simulations of theoretical intensity profiles using the Debye functions. The method was applied to the analysis of synchrotron X-ray diffraction data of GaN and SiC nanocrystals. A presence of strained surface shell and a considerable internal pressure (GaN) in the nanoparticles was concluded.