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Bearing provides continuous, smooth movement of the cat's-eye mirror, eliminating wear and deterioration of bearing surface and resulting oscillation effects in servo system. Design features self-aligning configuration; single-point, pivotal pad mounting, having air passage through it; and design of pads that allows for precise control of discharge path of air from pads.
Palomar data published by Wilson et al. (1959) on Orion Nebula wavelength 3726 and 5007 forbidden OII and OIII emission lines have been used to construct a presented pair of contour maps of isovelocities in intervals of 2.5 km/sec. The space motions of theta-1 and theta-2 Ori stars and nebula measurements are discussed.
The results of numerical integrations of three-dimensional equations of motion of ions subject to given electric and magnetic fields are presented. The fields represent those which may exist in the pinch phase of the plasma focus, although here they depend only on the radial coordinate. The ions initially have Maxwellian velocity distributions, and their trajectories are interpreted in terms of single-particle constants of the motion. Two models of the axial electric field Ez are considered. For strong Ez away from the axis, there is a cyclotron acceleration which leads to ion heating. For positive Ez on the axis, ions within a Larmor radius of the axis undergo very efficient acceleration; the results for this new model are in general agreement with experimental results.
Hyder advocated the idea that the optical (H-alpha) flares can be identified with the response of the solar chromosphere to an infalling material stream resulting from the 'disparition brusque' of a prominence. Since some flares are observed without any apparent association with infalling streams, in this paper we examine the possibility of identifying the optical flare with the response of the chromosphere to a supersonic disturbance, i.e., a shock, propagating downward. The undisturbed chromosphere is represented by the Harvard-Smithsonian Reference Atmosphere and the evolution of the shock is evaluated with the use of the CCW (Chisnell, Chester, Whitham) approximation based on the theory of characteristics. It is shown that the chromosphere is heated by the shock, that radiation is enhanced, and that the enhanced radiation terminates the shock around the height of the temperature minimum.
A solution is given to the problem of a transient vibration process in a fastened plate, during a sudden displacement of the edge. Some partial cases of excitation are examined in which the packing can be calculated and the explicit type of change in a deformation over time can be found. Some examples are presented.
The response of molten metals to mechanical and thermal driving forces in nominal and microgravity is analyzed both theoretically and experimentally. The magnitude and transient behavior of internal fluid circulations, surface deformations, and globule trajectories and their effects on solidification in the Skylab electron beam sphere forming and metals melting experiments are determined. The theoretical approach consists of dimensional analysis of the governing differential equations. Experimental aspects include evaluation of specimens from terrestrial, KC-135 research aircraft, and actual Skylab tests and analysis of high speed movies taken during the melting processes. Several gravity variations and gravity independent results were successfully predicted based on expected differences and similarities in fluid dynamics.
Examination of the velocity structure of J = 1 to J = 0 emission of CO in the Orion A molecular cloud, including a presentation of extended strip maps in both declination and right ascension intersecting at the position of peak intensity. The results in declination show evidence for large-scale rotation, while the right ascension maps show features which can be interpreted as gravitational condensations. The observed rotation is found to be sufficient to support a density equal to that estimated for the cloud (an H2 number density of about 2000 per cu cm).
Biomechanics were studied of locomotion in a rotating environment like that of a space station at various gravity levels. Comparisons were made of the walking gait patterns and the amplitudes of various leg muscle electrical outputs at different gravity levels. The results of these tests are applicable to planning future space missions by providing a part of the information that will be needed to determine the type of vehicle and the gravity level to be provided for the astronauts if it is decided that artificial gravity is to be utilized.
The particle density and the magnetic-field intensity and direction are calculated for volume elements of the solar wind as a function of the initial magnetic-field direction and the initial speed gradient. It is assumed that the velocity is constant and radial. These assumptions are approximately valid between about 0.1 and 1.0 AU for many streams. Time profiles of the particle density, field intensity, and velocity are calculated for corotating streams, neglecting effects of pressure gradients. The compression and rarefaction of the magnetic field depend sensitively on the initial field direction. By averaging over a typical stream, it is found that the average radial field intensity is inversely proportional to the square of the heliocentric distance, whereas the average intensity in the direction of the planets' motion does not vary in a simple way, consistent with deep space observations. Changes of field direction may be very large, depending on the initial angle; but when the initial angle at 0.1 AU is such that the base of the field line corotates with the sun, the spiral angle is the preferred direction at 1 AU. The theory is also applicable to nonstationary flows.
A strict lower limit is derived for the laboratory kinetic energy of a magnetic monopole produced from a target at rest. The production of a monopole-antimonopole pair via the collision of a projectile with a target at rest in the laboratory is analyzed in terms of the velocity of the zero-momentum frame, the velocity of the monopole in that frame, and the velocity of the monopole in the laboratory. The limit obtained is applied to the data of Price et al. (1975), and almost all means of producing the monopole in the atmosphere immediately above the balloon-borne detectors are ruled out. Some mechanisms for slowing a monopole following its production are briefly considered.
An estimate for the coefficient of self-diffusion can be derived whenever the Eulerian velocity spectrum is known. The result is more general than those previously obtained. A comparison is made with computed test-particle diffusion in an inviscid two-dimensional Navier-Stokes fluid.
The results of numerical integrations of the three-dimensional relativistic equations of motion of electrons subject to given electric and magnetic fields are presented. Fields due to two different models are studied: (1) a circular distribution of current filaments, and (2) a uniform current distribution; both the collapse and the current reduction phases are studied in each model. Decreasing current in the uniform current model yields 100 keV electrons accelerated toward the anode and, as for earlier ion computations, provides general agreement with experimental results.
Based on studies of ophiolitic complexes, a characterization of basaltic magmas at midocean ridges is proposed. A thin molten region about 3 km wide probably exists at the top of the magma chamber; primitive material enters the uppermost part of the chamber from below, and fractionated material is removed by the upward extrusion of dikes and settling of crystals to form a mush which probably fills the bulk of the chamber. The roof of the magma chamber is probably cooler than the melting temperature of primitive basalt. Secondary melts and the volume of the uppermost molten region are considered. Weaknesses along the line of dike intrusion and limited plating of material onto the roof of the chamber may restrict dike intrusion to the exceeding narrow zone inferred from ophiolitic complexes.
The possibility of using quaternions to describe the position of a gyroscope with a given rotating vector is discussed.
The concept evaluation shows that the four cylinder double acting U type Stirling engine with annular regenerators is the most suitable engine type for the 15 kW solar application with respect to design, performance and cost. Results show that near term performance for a metallic Stirling engine is 42% efficiency. Further improved components show an impact on efficiency of the future metallic engine to 45%. Increase of heater temperature, through the introduction of ceramic components, contribute the greatest amount to achieve high efficiency goals. Future ceramic Stirling engines for solar applications show an efficiency of around 50%.
A description is presented of the computational procedures used to obtain spatial fields of relative vorticity, advection of vorticity, horizontal divergence, and vertical motion. An investigation is conducted of the effectiveness of these procedures to reduce the effects of deliberately introduced random errors, giving attention to the confidence which can be placed on values of the derived parameters. It is concluded that fields of 500 mb vorticity and 700 mb vertical velocity, which are frequently used in synoptic scale forecasting schemes, show minimal effects of the deliberately introduced errors. Vorticity advection is found to be the most sensitive term to input data errors. Large fluctuations in fields of this parameter are evident both statistically and qualitatively.
The motion of the Jovian commensurability resonances during the early evolution of the solar system induced by the dissipation of the accretion disk results in fundamental differences in the celestial mechanics of objects over which a resonance passes from that observed for a stationary resonance. Objects experiencing resonance passage acquire irreversible increases of average eccentricity to large values accounting for the present-day random velocities of the asteroids. Semi-major axes are similarly irreversibly decreased by amounts capable of clearing the Kirkwood gaps. The gap widths are in agreement with observation.
Characteristics of good computerized analysis software are suggested. These general remarks and an overview of representative software precede a more detailed discussion of load support system analysis program structure. Particular attention is directed at a recent cylindrical roller bearing analysis as an example of the available design tools. Selected software modules are then examined to reveal the detail inherent in contemporary analysis. This leads to a brief section on current design computation which seeks to suggest when and why computerized analysis is warranted. An example concludes the argument offered for such design methodology. Finally, remarks are made concerning needs for model development to address effects which are now considered to be secondary but are anticipated to emerge to primary status in the near future.