515 research outputs found

    Laser measuring system for incremental assemblies

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    Wire-wrapped frame assemblies used in spark chambers and the like can be measured using a system which utilizes a laser, an interferometer, and a retroreflector to precisely measure distance. A light source and a photodetector are located adjacent the incremental assembly and mounted on a movable carriage. The interferometer is also mounted on the movable carriage, while the laser and retroreflector are positioned at either end of the carriage track. The carriage is moved along one edge of the incremental assembly between the retroreflector and the laser, and as the carriage is moved, the light from the light source to the photodetector is interrupted. This produces a trigger command to a control unit which in turn causes a distance measurement to be made. A printout is provided for each sampling trigger command to list such items as ideal position, actual position and amount of error

    Laser measuring system for wire-wrapped frame assemblies

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    The laser measuring system is designed to automatically measure and record the distances between small diameter wires on a wire wrapped grid frame assembly to an accuracy of 0.00635 mm (0.00025 in.). The system utilizes a helium-neon gas laser beam as the measuring instrument with a remote interferometer and retroreflector, a light source and photodetector to detect the wire positions, in conjunction with recording, display and printout units. The laser measuring system is utilized to perform precise automatic measurements for wire application machines or as an automatic feedback device for positioning wires and/or to adjust them for out of tolerance conditions

    Manufacturing and test procedures for Aerobee 350 burst diaphragms

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    Manufacturing and test procedures for fuel and oxidizer burst diaphragms for Aerobee 350 propellant start valve

    GSFC Venus atmosphere simulator

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    The design and preliminary testing of a Venus Atmosphere Simulation System are described. The system was designed for testing a quadrupole mass spectrometer proposed for the Pioneer-Venus Experiment. The system is capable of providing programmed temperature cycles up to 550 C, and manually controlled pressure up to 100 atmospheres

    Evaluation of meta-benzenedisulfonic acid as a stress-reducing additive in a Watts nickel electroplating bath

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    Internal stress and deposit hardness of nickel electrodeposited containing controlled quantities of meta-benzenedisulfonic aci

    Areas of irregular, discontinuous patterns rapidly and accurately measured

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    Simple, rapid method measures the surface area of a pattern such as comprised by the conductors on a printed circuit board. A negative or positive film of the circuit layout is placed over a uniformly illuminated translucent surface and the proportion of light transmitted to silicon solar cells is determined

    Multidimensional Gaussian sums arising from distribution of Birkhoff sums in zero entropy dynamical systems

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    A duality formula, of the Hardy and Littlewood type for multidimensional Gaussian sums, is proved in order to estimate the asymptotic long time behavior of distribution of Birkhoff sums SnS_n of a sequence generated by a skew product dynamical system on the T2\mathbb{T}^2 torus, with zero Lyapounov exponents. The sequence, taking the values ±1\pm 1, is pairwise independent (but not independent) ergodic sequence with infinite range dependence. The model corresponds to the motion of a particle on an infinite cylinder, hopping backward and forward along its axis, with a transversal acceleration parameter α\alpha. We show that when the parameter α/π\alpha /\pi is rational then all the moments of the normalized sums E((Sn/n)k)E((S_n/\sqrt{n})^k), but the second, are unbounded with respect to n, while for irrational α/π\alpha /\pi, with bounded continuous fraction representation, all these moments are finite and bounded with respect to n.Comment: To be published in J. Phys.

    On Density of State of Quantized Willmore Surface-A Way to Quantized Extrinsic String in R^3

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    Recently I quantized an elastica with Bernoulli-Euler functional in two-dimensional space using the modified KdV hierarchy. In this article, I will quantize a Willmore surface, or equivalently a surface with the Polyakov extrinsic curvature action, using the modified Novikov-Veselov (MNV) equation. In other words, I show that the density of state of the partition function for the quantized Willmore surface is expressed by volume of a subspace of the moduli of the MNV equation.Comment: AMS-Tex Us

    Statistical Mechanics of Elastica on Plane as a Model of Supercoiled DNA-Origin of the MKdV hierarchy-

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    In this article, I have investigated statistical mechanics of a non-stretched elastica in two dimensional space using path integral method. In the calculation, the MKdV hierarchy naturally appeared as the equations including the temperature fluctuation.I have classified the moduli of the closed elastica in heat bath and summed the Boltzmann weight with the thermalfluctuation over the moduli. Due to the bilinearity of the energy functional,I have obtained its exact partition function.By investigation of the system,I conjectured that an expectation value at a critical point of this system obeys the Painlev\'e equation of the first kind and its related equations extended by the KdV hierarchy.Furthermore I also commented onthe relation between the MKdV hierarchy and BRS transformationin this system.Comment: AMS-Tex Us
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