Synthesis of improved feeds for large circular paraboloids.
Improved feed synthesis using multimodes for large circular paraboloids at Parkes
PARABOLIC REFLECTOR↗
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Shock and vibration response of multistage structure
Study of the shock and vibration response of a multistage structure employed analytically, lumped-mass, continuous-beam, multimode, and matrix-iteration methods. The study was made on the load paths, transmissibility, and attenuation properties along a longitudinal axis of a long, slender structure with increasing degree of complexity.
Lee, S. Y.↗
Measurements on a near-confocal optical resonator.
Near confocal optical resonator measurements for multimode power output of carbon dioxide laser
Mcelroy, J. H.↗
Mode locking and ultrashort laser pulses by anisotropic molecular liquids.
Anisotropic molecular liquid in optical resonator of multimode laser
Laussade, J. P.↗
Improved circularly polarized planar-array antenna
Slots sitting astride the virtual wall in a multimode wave guide can be used for generation of one component of a circularly polarized beam. There is a high degree of efficiency without the use of a slow-wave structure.
Seaton, A. F.↗
Experiments and a model for pilot dynamics with visual and motion inputs
Multimodality pilot model for visual and motion feedbacks derived from simulator program
Alex, F. R.↗
Preliminary report on recent improvements in the analysis of surface waves.
Moving window analysis digital technique for complex seismic surface waves in presence of noise and multimode propagation
Dziewonski, A.↗
Aerospace sensor systems.
Aerospace sensor systems, discussing adaptive multimode sensors and multispectral sensing, electronic recognition of image components, laser radar and Raman scattering technique
Mannella, G. G.↗
A technique for the analysis of transient seismic signals.
Multiple filter technique for seismic multimode dispersed signals, checking time and frequency resolution by diagnostic diagram
Bloch, S.↗
Adaptive computing techniques
Adaptive local algorithm and convergence speed of multimodal multidimensional function
Schmitt, E.↗
Radiometric evaluation of antenna-feed component losses
Radiometric method for calibrating loss of multimode antenna-feed components with linear or circular polarization, deriving calibration and error analysis equations
Otoshi, T. Y.↗
Composite antenna feed system operates from VHF to X-band
System has high radiation efficiency and minimal interaction between elements when inserted between a multimode, multifrequency transponder and a parabolic reflector in an airborne communications system.
Jakstys, V.↗
Development of a satellite microwave radiometer to sense the surface temperature of the world oceans
A proposed S-band radiometer for determining the ocean surface temperature with an absolute accuracy of + or - 1 Kelvin and a resolution of + or - .1 Kelvin was placed under the Advanced Applications Flight Experiment for further development into Nimbus readiness state. The results of assessing the following are described: effects due to the state of the sea surface, effects caused by the intervening atmosphere, and effects associated with imperfections in the instrument itself. An extensive sea truth program is also described for correlation of aircraft test flight measurements or of satellite remote measurement to in-situ data. An improved radiometer design is a modified Dicke-switch type with temperature stabilized, microwave integrated circuit, front-end and with a pulsed injection-noise nulling system. The radiometer has a multimode rectangular horn antenna with very low ohmic losses and a beam efficiency of 98% or better.
Hidy, G. M.↗
Application of the Galerkin Method in the Design of Stable Liquid Rocket Motors
A brief description of results obtained in the continuing investigations is presented. The following areas are covered: (1) the development of the third-order, multimode theory to study the behavior of large amplitude transverse instabilities, (2) nonlinear axial mode instability, and (3) the influence of the functional form of the unsteady combustion response function upon the stability characteristics of rocket motors. Also a study was begun to improve the second order potential theory in order to provide a better approximation to the nozzle boundary condition.
Zinn, B. T.↗
Development of a model of machine hand eye coordination and program specifications for a topological machine vision system
A unified approach to computer vision and manipulation is developed which is called choreographic vision. In the model, objects to be viewed by a projected robot in the Viking missions to Mars are seen as objects to be manipulated within choreographic contexts controlled by a multimoded remote, supervisory control system on Earth. A new theory of context relations is introduced as a basis for choreographic programming languages. A topological vision model is developed for recognizing objects by shape and contour. This model is integrated with a projected vision system consisting of a multiaperture image dissector TV camera and a ranging laser system. System program specifications integrate eye-hand coordination and topological vision functions and an aerospace multiprocessor implementation is described.
Source record↗
Comparison of genetic algorithms with conjugate gradient methods
Genetic algorithms for mathematical function optimization are modeled on search strategies employed in natural adaptation. Comparisons of genetic algorithms with conjugate gradient methods, which were made on an IBM 1800 digital computer, show that genetic algorithms display superior performance over gradient methods for functions which are poorly behaved mathematically, for multimodal functions, and for functions obscured by additive random noise. Genetic methods offer performance comparable to gradient methods for many of the standard functions.
Bosworth, J. L.↗
Sonic-boom-induced building structure responses including damage.
Concepts of sonic-boom pressure loading of building structures and the associated responses are reviewed, and results of pertinent theoretical and experimental research programs are summarized. The significance of sonic-boom load time histories, including waveshape effects, are illustrated with the aid of simple structural elements such as beams and plates. Also included are discussions of the significance of such other phenomena as three-dimensional loading effects, air cavity coupling, multimodal responses, and structural nonlinearities. Measured deflection, acceleration, and strain data from laboratory models and full-scale building tests are summarized, and these data are compared, where possible, with predicted values. Damage complaint and claim experience due both to controlled and uncontrolled supersonic flights over communities are summarized with particular reference to residential, commercial, and historic buildings. Sonic-boom-induced building responses are compared with those from other impulsive loadings due to natural and cultural events and from laboratory simulation tests.
Clarkson, B. L.↗
Testing techniques and comparisons between theory and test for vibration modes of ring stiffened truncated-cone shells.
Vibration tests were carried out on truncated-cone shells with widely spaced ring stiffeners. The models were excited by an air shaker for LF modes and by small electrodynamic shakers for HF modes. The Novozhilov thin shell theory according to which a ring is an assembly of an arbitrary number of segments, each being a short truncated-cone shell of uniform thickness, is used in the analysis of the results. A mobile, noncontacting, displacement-sensitive sensor system developed by the author was used in the tests. Tests results are given for a free-free 60-deg cone and for a clamped-free 60-deg cone. The tests are characterized as having considerable value for the classification of prevalent multimode responses in shells of this type.
Naumann, E. C.↗