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Lorenzo, C. F.

Publications and source records attributed to Lorenzo, C. F..

30 records · Page 2
All sourcesNASA NTRSDOE OSTI
NASA NTRS1971

Variable sweep-rate shortens dynamic testing time

Method adjusts sweep frequency of tested system such that sweep is nominal when selected dynamic event occurs, but is rapid otherwise. Technique achieves time reductions of 7.5 to 1, maintains 0.5 percent accuracy in the results, and has several industrial applications.

Lorenzo, C. F.↗
NASA NTRS1971

Applications of symbolic computing methods to the dynamic analysis of large systems

Since the symbolic computing language is very well suited to the operations with algebraic equations, techniques use the transfer function concept as a tool for the analysis of large linear dynamic systems. Techniques were coded in the experimental symbolic computer language FORMAC. The first of these approaches, REDUCE 1, establishes the techniques and a computer program to symbolically reduce arbitrary block diagrams associated with large systems for desired transfer functions. Symbolic closed form solutions are determined in several forms including an expanded form in terms of the driving frequencies and system constants. Programs are also written to numerically evaluate the symbolic solutions. A second computer program, REDUCE 2, is also based on the use of symbolic computing methods and was written to accommodate large engineering systems.

Lorenzo, C. F.↗
NASA NTRS1968

Symbolic reduction of block diagrams using FORMAC

Two computer programs - one written in FORMAC to generate the desired symbolic expressions, the other in FORTRAN 4 to numerically evaluate the expressions are announced. The FORTRAN program accepts the symbolic punched output from the FORMAC program in either unexpanded or expanded form. It numerically evaluates the expressions.

Lorenzo, C. F.↗
NASA NTRS1968

Computer program determines system stability /DIGSTA/

Computer program implements a stability criterion that can be applied directly to the numerical solutions of systems of differential equations. The program accepts as input the time function of the system, a time to view the transient, and an acceptable amplitude boundary for any steady-state oscillation.

Lorenzo, C. F.↗