The equivalence of rank permutation codes to a new class of binary codes
Rank permutation codes equivalence to binary code class capable of generation and detection through direct and inverse transformations respectively
Chadwick, H. D.↗
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Observations of anomalous radiation at long wavelengths from Ic class variables
Ic class variables long wavelength anomalous radiation, discussing emission from circumstellar dust shell
Gehrz, R. D.↗
A class of nonlinear functions and the convergence of Gauss-Seidel and Newton-Gauss-Seidel iterations
Class on nonlinear functions and convergence of Gauss-Seidel and Newton-Gauss-Seidel iterations
More, J. J.↗
Control of a class of nonlinear distributed parameter systems via direct search on the performance index
Direct search of performance index for optimal control of class of nonlinear distributed parameter systems
Fan, L. T.↗
On classes of n-dimensional nonlinear mappings generalizing several types of matrices
Classes of n dimensional functions nonlinear matrix mapping, emphasizing block-Jacobi and block-Gauss-Seidel process convergence for continuous surjective M functions
Rheinboldt, W. C.↗
On classes of n-dimensional nonlinear mappings generalizing several types of matrices
Function classes of n-dimensional nonlinear mappings generalizing matrices, including convergence for Jacobi and Gauss-Seidel process
Rheinboldt, W. C.↗
Attitude control systems for load relief of Saturn-class launch vehicles
The effectiveness of attitude control laws that are designed to reduce bending moment loads and improve the controllability of large Saturn class boosters is discussed. These laws are referred to as load relief control systems. The two factors are assessed by simulations of varying degrees of complexity, from 2-D rigid body to 6-D with flexible body. A load relief control system, nicknamed AGE, is selected as the most effective of the various proposed schemes. This system is compared with other load relief laws and with simple attitude control. Most nominal vehicles use attitude control laws since their goal is to stay on the flight path without regard to the induced loads.
Sharp, J.↗
Calculative techniques for transonic flows about certain classes of wing body combinations
Procedures based on the method of local linearization and transonic equivalence rule were developed for predicting properties of transonic flows about certain classes of wing-body combinations. The procedures are applicable to transonic flows with free stream Mach number in the ranges near one, below the lower critical and above the upper critical. Theoretical results are presented for surface and flow field pressure distributions for both lifting and nonlifting situations.
Stahara, S. S.↗
Microscale photo interpretation of forest and nonforest land classes
Remote sensing of forest and nonforest land classes are discussed, using microscale photointerpretation. Results include: (1.) Microscale IR color photography can be interpreted within reasonable limits of error to estimate forest area. (2.) Forest interpretation is best on winter photography with 97 percent or better accuracy. (3.) Broad forest types can be classified on microscale photography. (4.) Active agricultural land is classified most accurately on early summer photography. (5.) Six percent of all nonforest observations were misclassified as forest.
Aldrich, R. C.↗
A passive balancer for a class of rotating spacecraft
Equations of motion are derived for a flexibly connected dual-spin spacecraft equipped with four pendulumlike passive controllers for mass balance and spin axis control. These equations are constrained and used to determine the conditions required for successful steady-state operation of the controllers with a spinning, rigid-body spacecraft. Generalized controller sizing criteria are derived and related to limiting values of system time constant for an example spacecraft unbalance condition. A generalized real-time computer simulation of a large, slowly spinning rigid-body spacecraft equipped with passive controllers is also presented. Numerical results of this simulation show that passive controllers can successfully balance a class of rotating rigid bodies undergoing large internal mass and inertial disturbances. The ratio of total controller mass to spacecraft mass need not be greater than 1 to 2 percent.
Martz, C. W.↗
Minimum-energy control of a class of electrically driven vehicles.
A minimum-energy controller is designed and built for a class of electrically driven vehicles according to the theoretical concepts determined by the application of modern control theory. Theoretical results are obtained by making several justifiable assumptions in the dynamical equations of the system and solving the resulting stochastic optimal control problem by Bellman's dynamic programming technique. Several practical and economical considerations are taken into account for the mechanization of the minimum-energy control law.
Sahinkaya, Y. E.↗
Isolated output for class-D dc amplifiers
Transformer-coupled output stage is used with pulse-width modulated class-D dc amplifiers. Circuit is comprised of two channels corresponding to negative and positive input signals. Amplitude of secondary-current triangular pulse is function of duration of driving pulse. Therefore, circuit converts pulse-width modulated driving signal to pulse-amplitude modulated signal.
Honnel, M. A.↗
Performance evaluation of a class of systematic, rate (M-1)/M, convolutional codes
The implementation and performance evaluation are described for a class of rate (M-1)/M, systematic, convolutional codes being decoded with a simple majority logic decoder. The encoding logic appends one parity bit for each PCM telemetry word. It is shown that over the critical range of received PCM telemetry signal-to-noise ratios, this coding procedure produces a net coding gain of from 1.5 to 2.5 db relative to an equal power transmission of uncoded PCM telemetry. Being a low-redundancy systematic code, it is possible to process this data without convolutional decoding with a small rate loss penalty of about 0.5 db.
Greene, E. P.↗
Comparing complexity classes of formal languages
A property of polynomial complete languages is extended in order to better compare various classes of formal languages defined by time- or tape-bounded turing machines.
Book, R. V.↗
Equivalence Classes of Constant Divergence and Related Results
The maximum likelihood procedure is used for dealing with the problem of classifying into one of m distinct n-variate classes, an arbitrary n-channel multispectral measurement vector x.
Decell, H. P., Jr.↗
A convergence theory for a class of nonlinear programming problems.
A recent convergence theory of Elkin concerning methods for unconstrained minimization is extended to a certain class of nonlinear programming problems. As in Elkin's original approach, the analysis of a variety of step-length algorithms is treated entirely separately from that of several direction algorithms. This allows for their combination into many different methods for solving the constrained problem. These include some of the methods of Rosen and Zoutendijk. We also extend the results of Topkis and Veinott to nonconvex sets and drop their requirement of the uniform feasibility of a subsequence of the search directions.
Rauch, S. W.↗
Cygnids and Taurids - Two classes of infrared objects.
In a study of the anonymous objects from the IRC Survey, we have found that about 10 percent have large long wave excesses. These infrared stars seem to belong to two classes, one group like NML Cygni (Cygnids) and the other like NML Tauri (Taurids).
Strecker, D. W.↗
On the controllability of a class of discrete bilinear systems.
The subject of this paper is the controllability of a class of time invariant discrete bilinear systems. Bilinear systems are classified into two categories: homogeneous and inhomogeneous. Necessity as well as the sufficiency results are obtained by means of decomposing the bilinear system into a linear system and a multiplicative feedback. By-products of the decomposition are the notions of multiplicative feedback compensation and the multiplicative feedback with bias compensation which may prove to be alternatives for the classical linear feedback compensation.
Goka, T.↗