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Plots of absorption line strength versus line position for wavenumbers from 0 to 17,900 cm(-1) are shown for 20 atmospheric gases (H2O, CO2, O3, N2O, CO, CH4, O2, NO, SO2, NO2, NH3, HNO3, OH, HF, HCl, HBr, HI, ClO, OCS, H2CO). Also shown are similar plots of lower-state energy values for adsorption lines for the strongly adsorbing atmospheric gases (H2O, CO2, O3, and CH4) for wavenumbers from 0 to 5000 cm(-1).
A near diffraction-limited telescope requires that tolerance analysis be done on the basis of system wavefront error. One method of analyzing the wavefront error is to represent the wavefront error function in terms of its Zernike polynomial expansion. A Ramsey-Korsch ray trace package, a computer program that simulates the tracing of rays through an optical telescope system, was expanded to include the Zernike polynomial expansion up through the fifth-order spherical term. An option to determine a 3 dimensional plot of the wavefront error function was also included in the Ramsey-Korsch package. Several assimulation runs were analyzed to determine the particular set of coefficients in the Zernike expansion that are effected by various errors such as tilt, decenter and despace. A 3 dimensional plot of each error up through the fifth-order spherical term was also included in the study. Tolerance analysis data are presented.
Processing continued on the data set covering the first three months of the mission. Orbits were selected over a specified range of longitude and latitude and those orbits falling within the geographical boundaries were stored on a disk and a listing made. To verify the quality of the data, plots were made showing altitude vs latitude, anomalous field vs latitude, and corrected anomalous field vs latitude. Results of the plotting showed that: (1) data from the first day of the mission are not usable because they are too noisy; (2) some orbits contain spikes, no doubt a processing error on the tape; (3) some orbits contain a 20 deg region in latitude, offset roughly 30 nT from the rest of the anomalous field profiles; and (4) the correlation between the adjacent orbits is poor. Even the new ring current coefficients provided with a later, corrected set of data tapes did not not yield the desired correlations.
A software interface package was written for use with a desktop computer and two models of single channel Fast Fourier analyzers. This software features a portable measurement and analysis system with several options. Two types of interface hardware can alternately be used in conjunction with the software. Either an IEEE-488 Bus interface or a 16-bit parallel system may be used. Two types of storage medium, either tape cartridge or floppy disc can be used with the software. Five types of data may be stored, plotted, and/or printed. The data types include time histories, narrow band power spectra, and narrow band, one-third octave band, or octave band sound pressure level. The data acquisition programming includes a front panel remote control option for the FFT analyzers. Data analysis options include choice of line type and pen color for plotting.
A computerized data bank system was developed for utilization of large amounts of vibration and acoustic data to formulate component random vibration design and test criteria. This system consists of a computer, graphics tablets, and a dry silver hard copier which are all desk top type hardware and occupy minimal space. Currently, the data bank contains data from the Saturn 5 and Titan 3 flight and static test programs. The vibration and acoustic data are stored in the form of power spectral density and one third octave band plots over the frequency range from 20 to 2000 Hz. The data were stored by digitizing each spectral plot by tracing with the graphics tablet. The digitized data were statistically analyzed, and the resulting 97.5 percent confidence levels were stored on tape along with the appropriate structural parameters. Standard extrapolation procedures were programmed for prediction of component random vibration test criteria for new launch vehicle and payload configurations. A user's manual is included to guide potential users through the programs.
Numerical methods were used to determine the effects of lubricant starvation on the minimum film thickness under conditions of a hydrodynamic point contact. Starvation was effected by varying the fluid inlet level. The Reynolds boundary conditions were applied at the cavitation boundary and zero pressure was stipulated at the meniscus or inlet boundary. A minimum-film-thickness equation as a function of both the ratio of dimensionless load to dimensionless speed and inlet supply level was determined. By comparing the film generated under the starved inlet condition with the film generated from the fully flooded inlet, an expression for the film reduction factor was obtained. Based on this factor a starvation threshold was defined as well as a critically starved inlet. The changes in the inlet pressure buildup due to changing the available lubricant supply are presented in the form of three dimensional isometric plots and also in the form of contour plots.
The magnetic disturbance fields caused by global external current systems are considered with particular emphasis on improving the understanding of the physical processes which control high latitude current systems. Following processing the MAGSAT data were routinely plotted in the Universal Time (UT) format as well as in a polar plot format. The H'D'U' coordinate system, was adopted as the standard for representing the MAGSAT residual magnetic field vectors. A data file was generated and the TPOLAR computer code was developed to determine from the orbital elements, the time, latitude, and MLT of the extremum latitude of each transpolar segment of orbit. The precision of the vector data set from MAGSAT prompted an extended exploratory phase for data analysis procedures, modeling techniques and phenomenology.
The effect of bearing thermal growth on the effectiveness of the bearing preload springs on the space shuttle main engine high pressure oxygen turbopump (SSME HPTOP) were examined. The SSME HPTOP turbine end bearings, preload spring, and bearing mounting design were evaluated relative to spalling, excessive ball wear, possible thermal problems, and cage delamination. The magnitude of the thermal stresses required to cause high levels of ball wear were calculated. Plots of maximum sheer stress and maximum reversing shear versus the axial load for the 57 mm SSME HPTOP bearing were created. A plot of the bearing thermal growth versus preload spring deflection was generated. It was determined that metallic wear, rather than thermal growth, caused enlargement of the contact zone between ball and races, that high fatigue-inducing shear stresses are generated under increased loads, and that at temperatures between 100 and 150 deg C, the springs bottom out and very high loads are developed in the bearing. Allowance for adequate spring movement after assembly is recommended.
A software package was developed for use with micro and minicomputers, particularly the LSI-11/DPD-11 series. The package has a number of Fortran-callable subroutines which perform a variety of frequently needed tasks for biomedical applications. All routines are well documented, flexible, easy to use and modify, and require minimal programmer knowledge of peripheral hardware. The package is also economical of memory and CPU time. A single subroutine call can perform any one of the following functions: (1) plot an array of integer values from sampled A/D data, (2) plot an array of Y values versus an array of X values; (3) draw horizontal and/or vertical grid lines of selectable type; (4) annotate grid lines with user units; (5) get coordinates of user controlled crosshairs from the terminal for interactive graphics; (6) sample any analog channel with program selectable gain; (7) wait a specified time interval, and (8) perform random access I/O of one or more blocks of a sequential disk file. Several miscellaneous functions are also provided.
User instructions for the Tektronix Graphics Package of the Automated Paneling Technique (APT) and the Wing and Body Aerodynamic Technique (WABAT) Programs are provided. Responses to plot package messages which the user must make to activate plot package operations and options are described. Modifications to the APT and WABAT input run streams, to affect the graphic interface, are also covered.
The 3-day images from the Nimbus 5 electrically scanning microwave radiometer were combined to form monthly average maps and contour plots. These show clearly the yearly cycle from minimum ice extent in February to maximum ice extent from August to September and the spatial distribution of ice 15 to 50 percent concentrated, 50 to 85 percent concentrated, and 85 to 100 percent concentrated. The yearly cycle of the monthly extent of ice is plotted for each of the four years (1973-76). The total 4-year range in monthly mean concentrations (over the 30 km x 30 km grid elements with ice present) is 50 to 80 percent, and the yearly cycle is far less distinct than that for the ice areas.
user instruction and software descriptions for the base program of the coupled rotor/airframe vibration analysis are provided. The functional capabilities and procedures for running the program are provided. Interfaces with external programs are discussed. The procedure of synthesizing a dynamic system and the various solution methods are described. Input data and output results are presented. Detailed information is provided on the program structure. Sample test case results for five representative dynamic configurations are provided and discussed. System response are plotted to demonstrate the plots capabilities available. Instructions to install and execute SIMVIB on the CDC computer system are provided.
The RF communications capabilities and nominally expected performance for the ascent phase of the second orbital flight of the shuttle are provided. Predicted performance is given mainly in the form of plots of signal strength versus elapsed mission time for the STDN (downlink) and shuttle orbiter (uplink) receivers for the S-band PM and FM, and UHF systems. Performance of the NAV and landing RF systems is treated for RTLS abort, since in this case the spacecraft will loop around and return to the launch site. NAV and landing RF systems include TACAN, MSBLS, and C-band altimeter. Signal strength plots were produced by a computer program which combines the spacecraft trajectory, antenna patterns, transmit and receive performance characteristics, and system mathematical models. When available, measured spacecraft parameters were used in the predictions; otherwise, specified values were used. Specified ground station parameter values were also used. Thresholds and other criteria on the graphs are explained.
A boundary element method computer program developed for heat transfer analysis of two dimensional composite structures is described. The program runs on a time share mode and interacts with the user for multirun analysis. During a run, the geometry can be modified interactively by the user as many times as desired by using various options available and the new results printed or plotted. A concept of plotting the results for boundary element method is introduced. The advantage of such a program over the finite element method for simple design problems is demonstrated.
The rate constants for the reaction CH3O2 + CH3O2 yields products (1) were measured in the temperature range from 248 to 417 K, taking into consideration pressures in the range from 60 to 700 torr of N2. The experimental investigation was carried out in a Pyrex flash photolysis system employing ultraviolet absorption detection. Methylperoxy radicals (CH3O2) were produced by the photolysis of Cl2-CH4-O2 mixtures. Rate constants were measured by observing the second-order disappearance of CH3O2 radicals. Plots of 1/(CH3O2 optical density) vs. time were observed to be linear over a concentration change of a factor of 10-50. Results of the kinetic runs at each temperature are summarized in a table, and an Arrhenius plot of the data is shown in a graph.
Von Rosenvinge and Paizis (1981) have discussed the amplitude variations of low energy cosmic rays, taking into account intensity-time variations which occurred starting in late 1973 and continued into mid-1975. The present investigation is concerned with the occurrence of so-called hysteresis effects during the considered period. A graph is presented which shows a comparison of the time-intensity plots for 35.3-82 MeV protons (340 MV) and the Deep River neutron monitor. A time lag can be observed between the neutron monitor intensity and the 35.3-82 MeV proton intensity. The same data is replotted to show a hysteresis loop. A plot for 35.1-82 MeV/n helium is also provided. It is found that all measured values of the time lag for protons and helium are consistent with those reported by Klecker et al. (1980). It is pointed out that the time lag for the anomalous helium is not consistent with the model of O'Gallagher (1975).
Method devised to obtain static shear stiffness data for membranes. Shear deflection of membrane measured under various applied static shear loads, and measurements plotted. Match attempted between experimental plot and predicted load-vs.-deflections curves until best fitting theoretical curve is found.
Curve-fitting procedure ensures high confidence levels. Threedimensional plot represents performance of small automatic transmission coasting in second gear. In equation for plot, PL power loss, S speed and T torque. Equations applicable to manual and automatic transmissions over wide range of speed, torque, and efficiency.