Solid state switch provides high input-to-output isolation

Switch uses a combination of N-channel and P-channel Metal Oxide Semiconductor Field Effect Transistors /MOSFET/ to obtain a normally open switch with no power applied. Series-shunt-series MOSFET switching achieves high input-output isolation

Preparing for the future

Summary of remarks by E. A. Trowbridge, Jr., vice-president, Wilson & Co., Inc., May 13, 1962, at the Block and Bridle Club spring awards banquet, University of Missouri, Columbia, Missouri--P. [3].Cover title

The use of a limited amount of molasses in fattening yearling steers

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Corn versus oats for work mules

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Fertilizer inspection, analysis and use, 1946

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Low velocity impact analysis with NASTRAN

A nonlinear elastic force-displacement relationship is used to calculate the transient impact force and local deformation at the point of contact between impactor and target. The nonlinear analysis and transfer function capabilities of NASTRAN are used to define a finite element model that behaves globally linearly elastic, and locally nonlinear elastic to model the local contact behavior. Results are presented for two different structures: a uniform cylindrical rod impacted longitudinally; and an orthotropic plate impacted transversely. Calculated impact force and transient structural response of the targets are shown to compare well with results measured in experimental tests

Near field performance of staged diffusers in shallow water

This work was performed by John H. Trowbridge as part of his masters thesis in the M.I.T. Dept. of Civil Engineering, 1979.Submerged diffusers are commonly used to dilute condenser cooling water from coastal power plants. A staged diffuser, in which the diffuser centerline is perpendicular to shore and the nozzles are direc- ted essentially offshore, is often used at sites where there is a long- shore, reversing current. Because of the symmetry of this design, dilution is improved by a longshore current in either direction, and the diffuser's position perpendicular to shore allows it to intercept a crossflow effectively. The performance of a staged diffuser in shallow water of constant depth has been analysed previously by treating the diffuser as a continuously distributed line source of momentum (Almquist and Stolzen- bach, 1976). This theory has been reviewed and extended to consider the case of a sloping bottom and to compute the external (entrainment) flow field set up by the diffuser. In these analyses the important parameters are the gross diffuser dimensions, including total flow rate, discharge velocity, water depth and diffuser length. Length scales are on the order of one diffuser length, and the characteristics of the individual jets are assumed to be insignificant in describing diffuser performance at this level. A more detailed analysis of staged diffuser performance in the near field is useful if one wishes to describe the temperatures and shear stresses experienced by organisms that are entrained into the diffuser plume. Length scales in this problem are on the order of the port spacing, and characteristics of the individual jets are very important at this level. Relevant diffuser dimensions are discharge velocity, port diameter D , port spacing, port elevation h, water depth H, and discharge orientation. A description of the near field at this level has been obtained by solving for the trajectories, velocities, temperatures and flow rates of individual jets. Boundary layer approximations are made similar to those used in the classical analysis of free turbulent jets, and the analysis includes the effects of shallow water, the flowfield set up by adjacent jets, and an ambient current. Theoretical predictions are compared with the results of an experimental program. The analysis is then used to evaluate different diffuser designs from the stand- point of temperature and shear stress exposure of entrained organisms

Agricultural research in Missouri : annual report of the Missouri Experiment Station, 1945-1946

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The cospectrum of stress-carrying turbulence in the presence of surface gravity waves

Author Posting. © American Meteorological Society, 2017. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Physical Oceanography 48 (2018): 29-44, doi:10.1175/JPO-D-17-0016.1.The cospectrum of the horizontal and vertical turbulent velocity fluctuations, an essential tool for understanding measurements of the turbulent Reynolds shear stress, often departs in the ocean from the shape that has been established in the atmospheric surface layer. Here, we test the hypothesis that this departure is caused by advection of standard boundary layer turbulence by the random oscillatory velocities produced by surface gravity waves. The test is based on a model with two elements. The first is a representation of the spatial structure of the turbulence, guided by rapid distortion theory, and consistent with the one-dimensional cospectra that have been measured in the atmosphere. The second model element is a map of the spatial structure of the turbulence to the temporal fluctuations measured at fixed sensors, assuming advection of frozen turbulence by the velocities associated with surface waves. The model is adapted to removal of the wave velocities from the turbulent fluctuations using spatial filtering. The model is tested against previously published laboratory measurements under wave-free conditions and two new sets of measurements near the seafloor in the coastal ocean in the presence of waves. Although quantitative discrepancies exist, the model captures the dominant features of the laboratory and field measurements, suggesting that the underlying model physics are sound.This research was supported by National Science Foundation Ocean Sciences Division Award 1356060 and the U.S. Geological Survey Coastal and Marine Geology Program

Silage for horses and mules

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