Geometric, aerodynamic, and kinematic characteristics of two twin keel parawings during deployment
Flight test data on geometric, aerodynamic, and kinematic characteristics of two twin keel parawings during deployment
Churchill, F. T.↗
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Problems of internal constitution and kinematics of main sequence stars
Internal constitution and kinematics of main sequence stars regarding age, evolution and formation place during hydrogen burning phase
Stroemgren, B.↗
Kinematic wave theory
Jacobian calculation in kinematic theory of wave propagation, using ray equation
Hayes, W. D.↗
Time-of-flight experiments in molecular motion and electron-atom collision kinematics
Time-of-flight measurements for relationship between velocity, mass and temperature in molecular gas motion and electron-atom collision kinematics
Donnelly, D. P.↗
Kinematic-dynamo action under incompressible, isotropic velocity turbulence
Regenerative kinematic-dynamo action under incompressible isotropic velocity turbulence, noting turbulent Lorentz force role
Lerche, I.↗
Kinematic reversal schemes for the geomagnetic dipole.
Fluctuations in the distribution of cyclonic convective cells, in the earth's core, can reverse the sign of the geomagnetic field. Two kinematic reversal schemes are discussed. In the first scheme, a field maintained by cyclones concentrated at low latitude is reversed by a burst of cyclones at high latitude. Conversely, in the second scheme, a field maintained predominantly by cyclones in high latitudes is reversed by a fluctuation consisting of a burst of cyclonic convection at low latitude. The precise fluid motions which produce the geomagnetic field are not known. However, it appears that, whatever the details are, a fluctuation in the distribution of cyclonic cells over latitude can cause a geomagnetic reversal.
Levy, E. H.↗
A sample computation of kinematic properties from cloud motion vectors.
Distributions of relative vorticity and balanced height have been computed from the cloud velocities associated with the cloud structure of an extratropical cyclone over the continental United States during a three-day period in March 1970. Cloud motions are assigned either to a 'mid-level,' or to a 'high level.' Derived vorticity and balanced height are compared with concurrent National Meteorological Center (NMC) analyses and also with similar kinematic quantities obtained from rawins at three constant-pressure levels. The computations of relative vorticity using mid-level cloud motion vectors show encouraging results. Patterns of computed cyclonic vorticity are related to the development, location, and movement of the surface cyclone. The analyses suggest that the 'mid-level' corresponds best to the 700-mb level. The vorticity analysis from the 'high-level' motion vectors presented difficulties.
Viezee, W.↗
SPACEBAR: Kinematic design by computer graphics
The interactive graphics computer program SPACEBAR, conceived to reduce the time and complexity associated with the development of kinematic mechanisms on the design board, was described. This program allows the direct design and analysis of mechanisms right at the terminal screen. All input variables, including linkage geometry, stiffness, and applied loading conditions, can be fed into or changed at the terminal and may be displayed in three dimensions. All mechanism configurations can be cycled through their range of travel and viewed in their various geometric positions. Output data includes geometric positioning in orthogonal coordinates of each node point in the mechanism, velocity and acceleration of the node points, and internal loads and displacements of the node points and linkages. All analysis calculations take at most a few seconds to complete. Output data can be viewed at the scope and also printed at the discretion of the user.
Ricci, R. J.↗
Kinematic stability of roller pairs in free rolling contact
A set of generalized stability equations was developed for roller pairs in free rolling contact. A symmetric, dual contact model was used. Four possible external contact profiles that possess continuous contacting surfaces were studied. It was found that kinematic stability would be insured if the larger radius of transverse curvature, in absolute value, and the smaller rolling radius both exist on the roller that has the apex of its conical surface outboard of its main body. The stability criteria developed are considered to be useful for assessing axial restraint requirements for a variety of roller mechanisms and in the selection of roller contact geometry for traction drive devices.
Savage, M.↗
Kinematical constraints on the observation of slow monopoles at the top of the atmosphere
Relativistic kinematics of monopole production and propagation in earth's atmosphere and magnetic field have been examined in the light of the observation of a magnetic monopole by Price et al. It has been shown that the observed monopole cannot result from nuclear interactions in the atmosphere and that the extraterrestrial origin of this monopole is very unlikely.
Badhwar, G. D.↗
Kinematics and spectra of planetary nebulae with O VI-sequence nuclei
Spectral features of NGC 5189 and NGC 6905 are tabulated. Fabry-Perot profiles around H alpha and O III lambda 5007 of NGC 5189, NGC 6905, NGC 246, and NGC 1535, are illustrated. The latter planetary nebula is a non-O VI-sequence, comparison object of high excitation. The kinematics of the four planetary nebulae are simply analyzed. Discussion of these data is motivated by the possibility of collisional excitation by high-speed ejecta from broad-lined O VI-sequence nuclei, and by the opportunity to make a comparison with conditions in the supernova remnant or ring nebula, G2.4 + 1.4, which contains an O VI-sequence nucleus of Population I.
Johnson, H. M.↗
Kinematic capability in the SVDS
The details of the Remote Manipulator System kinematic model implemented into the Space Vehicle Dynamics Simulation are given. Detailed engineering flow diagrams and definitions of terms are included.
Flanders, H. A.↗
Compatibility check of measured aircraft responses using kinematic equations and extended Kalman filter
An extended Kalman filter smoother and a fixed point smoother were used for estimation of the state variables in the six degree of freedom kinematic equations relating measured aircraft responses and for estimation of unknown constant bias and scale factor errors in measured data. The computing algorithm includes an analysis of residuals which can improve the filter performance and provide estimates of measurement noise characteristics for some aircraft output variables. The technique developed was demonstrated using simulated and real flight test data. Improved accuracy of measured data was obtained when the data were corrected for estimated bias errors.
Klein, V.↗
The local complex of O and B stars. II - Kinematics
The observed space velocities of O-B5 stars lying within about 1 kpc of the sun are analyzed. Motions examined include local solar motion, differential galactic rotation, mean peculiar stellar velocities, and systematic stellar motions parallel and perpendicular to the galactic plane. Kinematical determinations of the Oort constant and the K term for stars previously classified as members of the Gould and galactic belts are found to confirm earlier results that the Gould belt (or at least its youngest component) comprises a local perturbation in the general galactic velocity field. It is shown that if the Gould belt is expanding as a unit, its expansion age must be about 70 million years. The analyses also indicate negligibly small translational motion of the Gould belt relative to the galactic belt and parallel to the galactic plane as well as an approximate 'seesaw' motion of the Gould belt about the Cassiopeia-Carina line in the galactic plane. The age of the Gould belt is inferred to be either 20 or 60 million years from the vertical motions, which would imply the existence of either one or two waves of star formation as the Gould belt passed through the galactic belt either once or twice.
Frogel, J. A.↗
Coronal mass-ejections-kinematics of the 19 December 1973 event
A detailed description of the observed kinematics of the coronal disturbance of December 19, 1973, is presented along with inferences about the temperatures, densities, magnetic fields, and electric currents within the event. This disturbance consisted of the eruption of a previously quiescent prominence, an associated ejection of coronal material, and the destruction of a large coronal streamer. Observations of the prominence and the corona with a scanning spectroheliometer and a white-light coronagraph aboard Skylab before, during, and after the prominence eruption are discussed, and the temperature and density in the eruptive prominence are traced as the prominence rose to a height of 3 solar radii over 7 hr. The results obtained are shown to reinforce previous arguments that the material comprising the bulk of the mass ejected from the corona in transient events arises from the low corona rather than from the eruptive prominence, which may accompany the coronal mass ejection.
Schmahl, E.↗
A kinematic investigation of the influence of anvil air flow over convective nephsystems on high-level horizontal flow
The interactions between horizontal ambient flow and divergent wind fields, such as those that obtain atop cumulonimbus complexes, were investigated (theoretically) kinematically. The following were observed from the results of the analyses. First, for a particular divergent field, the relative mass flux over the area of the nephsystem decreased as the strength of the horizontal flow increased. Secondly, while in some of the cases analyzed the interaction between the two flows only resulted in the fanning out of streamlines and a slight redistribution in the wind speed, in many cases backflows and a total reorganization of the wind field occurred. Backflows have a blocking effect on the horizontal flow. Some of the computed patterns were compared with upper level cloud vectors (from geostationary satellite photographs). The comparison indicated that the computed resultant wind field could be used to explain some features of such satellite-derived wind fields.
Balogun, E. E.↗
Kinematic correction for roller skewing
A theory of kinematic stabilization of rolling cylinders is developed for high-speed cylindrical roller bearings. This stabilization requires race and roller crowning to product changes in the rolling geometry as the roller shifts axially. These changes put a reverse skew in the rolling elements by changing the rolling taper. Twelve basic possible bearing modifications are identified in this paper. Four have single transverse convex curvature in the rollers while eight have rollers with compound transverse curvature composed of a central cylindrical band of constant radius surrounded by symmetric bands with both slope and transverse curvature.
Savage, M.↗
On the combination of kinematics with flow visualization to compute total circulation - Application to vortex rings in a tube
To date the computation of the total circulation, or strength of a vortex has required detailed measurements of the velocity field within the vortex. In this paper a method is described in which the kinematics of the vortical flow field is exploited to calculate the strength of a vortex from relatively simple flow visualization measurements. There are several advantages in the technique, the most important being the newly acquired ability to calculate the transient changes in strength of a single vortex as it evolves. The method is applied to the study of vortex rings, although the development can be carried over directly to study vortex pairs, and it is expected that it can be generalized to other flows which contain regions of concentrated vorticity. The accuracy of the method as applied to vortex rings, assessed in part by comparing with the laser Doppler velocimeter (LDV) measurements of Sullivan et al., is shown to be excellent.
Brasseur, J. G.↗