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The theoretical basis for a new version of the SPLIT routine for CLASSY is described. (The SPLIT routine is used to guess the positions of the parts of a cluster which is not normally distributed). The proposed routine would be a faster, more accurate replacement for the existing SPLIT routine, which was developed on an ad hoc basis.
A detailed description of the machine-readable version of the atlas as it is currently beng distributed from the Astronomical Data Center is given. The data were obtained with the Oke multichannel scanner on the 5-meter Hale reflector for purposes of synthesizing galaxy spectra, and the digitized atlas contains normalized spectral energy distributions, computed colors, scan line and continuum indices for 175 selected stars covering the complete ranges of spectral type and luminosity class. The documentation includes a byte-by-byte format description, a table of the indigenous characteristics of the magnetic tape file, and a sample listing of logical records exactly as they are recorded on the tape.
A two-dimensional implicit finite-difference code is applied to the inviscid Euler equations to compute transonic flow past airfoils in order to provide well-documented standard test cases for the general user community. The code is an improved version of Steger's 1976 implicit code. Enhancements include the use of up-wind differencing in supersonic regions before shocks and a variable time step to accelerate convergence. An airfoil grid generation routine based on algebraic techniques is employed. The grids are clustered near shocks to improve resolution. Computed results are compared with other numerical results from the literature.
The new edition of the AFGL trace gas compilation is described. The latest version provides the necessary parameters for the computation of absorption or emission spectra of major bands of twenty-one gases in the region from 0 to 10,000 per cm. Emphasis in this edition has been on the addition of numerous millimeter and submillimeter transitions, the inclusion of bands of significance in upper atmospheric processes, and strong IR bands of trace constituents likely to be used for remote detection. The sources for the additions and modifications of the absorption parameters are summarized.
Integrated Procurement Management System, Version II (IPMS II) is online/ batch system for collecting developing, managing and disseminating procurementrelated data at NASA Johnson Space Center. Portions of IPMS II adaptable to other procurement situations.
Detailed descriptions of the three files of the machine-readable catalog are given. The files of the original tape have been restructured and the data records reformatted to produce a uniform data file having a single logical record per star and homogeneous data fields. The characteristics of the tape version as it is presently being distributed from the Astronomical Data Center are given and the changes to the original tape supplied are described.
The machine readable catalog, as it is distributed from the Astronomical Data Center, is described. Some minor reformatting of the magnetic tape version is received to decrease the record size and conserve space; the data content is identical to the sample shown in Table VI of the source reference.
The machine readable catalog is described. The machine version contains the same data as the published table, which includes a second file with the notes. The computerized data files are prepared at the Astronomical Data Center. Detected discrepancies and cluster identifications based on photometric estimators are included.
A revised and corrected version of the machine-readable catalog has been prepared. Cross identifications of the GC stars to the HD and DM catalogs have been replaced by data from the new SAO-HD-GC-DM Cross Index (Roman, Warren and Schofield 1983), including component identifications for multiple SAO entries having identical DM numbers in the SAO Catalog, supplemental Bonner Durchmusterung stars (lower case letter designations) and codes for multiple HD stars. Additional individual corrections have been incorporated based upon errors found during analyses of other catalogs.
The existence of local a posteriori error indicators for the p-version of the finite element method is demonstrated through numerical examples. It is shown that it is possible to construct reliable error indicators from the residuums and tractions which have the same rate of convergence as the strain energy. The error indicators contribution of an element can be estimated by considering only the element and its immediate neighbors. The optimal sequence of p-distributions can be closely followed by the indicators even when there are only a very few elements, the elements vary greatly in size, the polynomial orders vary, the mesh grading is poor, and the smoothness indices and relative errors vary between wide limits.
A new general-purpose optimization program for engineering design is described. ADS-1 (Automated Design Synthesis - Version 1) is a FORTRAN program for solution of nonlinear constrained optimization problems. The program is segmented into three levels, being strategy, optimizer, and one-dimensional search. At each level, several options are available so that a total of over 100 possible combinations can be created. Examples of available strategies are sequential unconstrained minimization, the Augmented Lagrange Multiplier method, and Sequential Linear Programming. Available optimizers include variable metric methods and the Method of Feasible Directions as examples and one-dimensional search options include polynomial interpolation and the Golden Section method as examples. Emphasis is placed on ease of use of the program. All information is transferred via a single parameter list. Default values are provided for all internal program parameters such as convergence criteria, and the user is given a simple means to over-ride these, if desired. The program is demonstrated with a simple structural design example.
A proposed total strainrange version of strainrange partitioning (SRP) to enhance the manner in which SRP is applied to life prediction is considered with emphasis on how advanced reliability technology can be applied to perform risk analysis and to derive safety check expressions. Uncertainties existing in the design factors associated with life prediction of a component which experiences the combined effects of creep and fatigue can be identified. Examples illustrate how reliability analyses of such a component can be performed when all design factors in the SRP model are random variables reflecting these uncertainties. The Rackwitz-Fiessler and Wu algorithms are used and estimates of the safety index and the probablity of failure are demonstrated for a SRP problem. Methods of analysis of creep-fatigue data with emphasis on procedures for producing synoptic statistics are presented. An attempt to demonstrate the importance of the contribution of the uncertainties associated with small sample sizes (fatique data) to risk estimates is discussed. The procedure for deriving a safety check expression for possible use in a design criteria document is presented.
The machine-readable version of the Astronomical Netherlands Satellite ultraviolet photometry catalog is described in detail, with a byte-by-byte format description and characteristics of the data file given. The catalog is a compilation of ultraviolet photometry in five bands, within the wavelength range 155 nm to 330 nm, for 3573 mostly stellar objects. Additional cross reference data (object identification, UBV photometry and MK spectral types) are included in the catalog.
The machine-readable version of the Atlas as it is currently being distributed from the Astronomical Data Center is described. The data were obtained with the Oke multichannel scanner on the 5-meter Hale reflector for purposes of synthesizing galaxy spectra, and the digitized Atlas contains normalized spectral energy distributions, computed colors, scan line and continuum indices for 175 selected stars covering the complete ranges of spectral type and luminosity class. The documentation includes a byte-by-byte format description, a table of the indigenous characteristics of the magnetic tape file, and a sample listing of logical records exactly as they are recorded on the tape.
A detailed description of the machine-readable revised catalog as it is currently being distributed from the Astronomical Data Center is given. This catalog of star images was compiled from imagery obtained by the Naval Research Laboratory (NRL) Far-Ultraviolet Camera/Spectrograph (Experiments S201) operated from 21 to 23 April 1972 on the lunar surface during the Apollo 16 mission. The documentation includes a detailed data format description, a table of indigenous characteristics of the magnetic tape file, and a sample listing of data records exactly as they are presented in the machine-readable version.
The machine-readable finding list, as it is currently being distributed from the Astronomical Data Center, is described. This version of the list supersedes an earlier one (1977) containing only Sections 1 through 7 of the NSRDS-NBS 3 multiplet tables publications. Additional sections are to be incorporated into this list as they are published.
A new general-purpose optimization program for engineering design is described. ADS (Automated Design Synthesis - Version 1.10) is a FORTRAN program for solution of nonlinear constrained optimization problems. The program is segmented into three levels: strategy, optimizer, and one-dimensional search. At each level, several options are available so that a total of over 100 possible combinations can be created. Examples of available strategies are sequential unconstrained minimization, the Augmented Lagrange Multiplier method, and Sequential Linear Programming. Available optimizers include variable metric methods and the Method of Feasible Directions as examples, and one-dimensional search options include polynomial interpolation and the Golden Section method as examples. Emphasis is placed on ease of use of the program. All information is transferred via a single parameter list. Default values are provided for all internal program parameters such as convergence criteria, and the user is given a simple means to over-ride these, if desired.
An updated procedure for characterizing an alloy and predicting cyclic life by using the total strain range version of strainrange partitioning (TS-SRP) has been developed. The principal feature of this update is a new procedure for determining the intercept of time dependent elastic strain range versus cyclic life lines. The procedure is based on an established relation between failure and the cyclic stress-strain response of an alloy. The stress-strain response is characterized by empirical equations presented in this report. These equations were determined with the aid of a cyclic constitutive model. The procedures presented herein reduce the testing required to characterize an alloy. Failure testing is done only in the high strain, low life regime; cyclic stress-strain response is determined from tests conducted in both the high and low strain regimes. These tests are carried out to stability of the stress-strain hysteresis loop but not to failure. Thus both the time and costs required to characterize an alloy are greatly reduced. This approach was evaluated and verified for two nickel base superalloys, AF2-1DA and Inconel 718.