13 research outputs found
Program for the transient response of ablating axisymmetric bodies including the effects of shape change
Governing differential equation, boundary conditions for the analysis on which computer program is based, and method of solution of resulting finite difference equations are discussed in the documentation
Solution of a large hydrodynamic problem using the STAR-100 computer
A representative hydrodynamics problem, the shock initiated flow over a flat plate, was used for exploring data organizations and program structures needed to exploit the STAR-100 vector processing computer. A brief description of the problem is followed by a discussion of how each portion of the computational process was vectorized. Finally, timings of different portions of the program are compared with equivalent operations on serial machines. The speed up of the STAR-100 over the CDC 6600 program is shown to increase as the problem size increases. All computations were carried out on a CDC 6600 and a CDC STAR 100, with code written in FORTRAN for the 6600 and in STAR FORTRAN for the STAR 100
Star adaptation for two-algorithms used on serial computers
Two representative algorithms used on a serial computer and presently executed on the Control Data Corporation 6000 computer were adapted to execute efficiently on the Control Data STAR-100 computer. Gaussian elimination for the solution of simultaneous linear equations and the Gauss-Legendre quadrature formula for the approximation of an integral are the two algorithms discussed. A description is given of how the programs were adapted for STAR and why these adaptations were necessary to obtain an efficient STAR program. Some points to consider when adapting an algorithm for STAR are discussed. Program listings of the 6000 version coded in 6000 FORTRAN, the adapted STAR version coded in 6000 FORTRAN, and the STAR version coded in STAR FORTRAN are presented in the appendices
Vectorization on the star computer of several numerical methods for a fluid flow problem
A reexamination of some numerical methods is considered in light of the new class of computers which use vector streaming to achieve high computation rates. A study has been made of the effect on the relative efficiency of several numerical methods applied to a particular fluid flow problem when they are implemented on a vector computer. The method of Brailovskaya, the alternating direction implicit method, a fully implicit method, and a new method called partial implicitization have been applied to the problem of determining the steady state solution of the two-dimensional flow of a viscous imcompressible fluid in a square cavity driven by a sliding wall. Results are obtained for three mesh sizes and a comparison is made of the methods for serial computation
A smoothing algorithm using cubic spline functions
Two algorithms are presented for smoothing arbitrary sets of data. They are the explicit variable algorithm and the parametric variable algorithm. The former would be used where large gradients are not encountered because of the smaller amount of calculation required. The latter would be used if the data being smoothed were double valued or experienced large gradients. Both algorithms use a least-squares technique to obtain a cubic spline fit to the data. The advantage of the spline fit is that the first and second derivatives are continuous. This method is best used in an interactive graphics environment so that the junction values for the spline curve can be manipulated to improve the fit
Piezoresistivity, mechanisms and model of cement-based materials with CNT/NCB composite fillers
Using 3-D GIS in Archaeology Classrooms: An Example from Hells Canyon, Oregon
Excavation data from an ancestral Nez Perce dwelling in Hells Canyon, Oregon (1600–500 B.P.) are used to integrate 3-D GIS and spatio-temporal problem-solving for university-level archaeology instruction. By working through three sequential projects, students learn visualization skills as well as archaeological methods, spatial thinking, and problem-solving. These projects include digital excavation of a house site with evaluation of the spatio-temporal relationships and patterns of artifacts, group analysis of different occupation layers, and 3-D visualization. Beyond this, students were encouraged to continue to explore areas of interest, develop new research questions, and complete more detailed studies as independent research efforts. Applications like 3-D GIS have the potential to reach many more students and dramatically increase student interest in and understanding of archaeology, using computer methods as a supplement to field work