5,447 research outputs found

    Granular discharge rate for submerged hoppers

    Get PDF
    The discharge of spherical grains from a hole in the bottom of a right circular cylinder is measured with the entire system underwater. We find that the discharge rate depends on filling height, in contrast to the well-known case of dry non-cohesive grains. It is further surprising that the rate increases up to about twenty five percent, as the hopper empties and the granular pressure head decreases. For deep filling, where the discharge rate is constant, we measure the behavior as a function of both grain and hole diameters. The discharge rate scale is set by the product of hole area and the terminal falling speed of isolated grains. But there is a small-hole cutoff of about two and half grain diameters, which is larger than the analogous cutoff in the Beverloo equation for dry grains

    Coherent control for the spherical symmetric box potential in short and intensive XUV laser fields

    Full text link
    Coherent control calculations are presented for a spherically symmetric box potential for non-resonant two photon transition probabilities. With the help of a genetic algorithm (GA) the population of the excited states are maximized and minimized. The external driving field is a superposition of three intensive extreme ultraviolet (XUV) linearly polarized laser pulses with different frequencies in the femtosecond duration range. We solved the quantum mechanical problem within the dipole approximation. Our investigation clearly shows that the dynamics of the electron current has a strong correlation with the optimized and neutralizing pulse shape.Comment: 11 Pages 3 Figure

    The Lure Crop Alternative

    Get PDF
    Lure crops are proposed as an alternative to scaring waterfowl. The lure crop works on the principle of permitting waterfowl to feed undisturbed for the duration of the damage season in an unharvested field of their choice thereby utilizing trampled grain. Waterfowl from adjacent areas are encouraged to use the lure crop through the use of scaring devices placed in protected fields. General criteria for implementation of a lure crop project and specific criteria for lure crop purchases are presented. Factors contributing to a successful lure crop and problems which reduced lure crop effectiveness are identified. Benefit/ cost analysis of lure crops was completed

    Ideal Bose gas in fractal dimensions and superfluid 4^4He in porous media

    Full text link
    Physical properties of ideal Bose gas with the fractal dimensionality between D=2 and D=3 are theoretically investigated. Calculation shows that the characteristic features of the specific heat and the superfluid density of ideal Bose gas in fractal dimensions are strikingly similar to those of superfluid Helium-4 in porous media. This result indicates that the geometrical factor is dominant over mutual interactions in determining physical properties of Helium-4 in porous media.Comment: 13 pages, 6 figure

    Parea: multi-view ensemble clustering for cancer subtype discovery

    Full text link
    Multi-view clustering methods are essential for the stratification of patients into sub-groups of similar molecular characteristics. In recent years, a wide range of methods has been developed for this purpose. However, due to the high diversity of cancer-related data, a single method may not perform sufficiently well in all cases. We present Parea, a multi-view hierarchical ensemble clustering approach for disease subtype discovery. We demonstrate its performance on several machine learning benchmark datasets. We apply and validate our methodology on real-world multi-view cancer patient data. Parea outperforms the current state-of-the-art on six out of seven analysed cancer types. We have integrated the Parea method into our developed Python package Pyrea (https://github.com/mdbloice/Pyrea), which enables the effortless and flexible design of ensemble workflows while incorporating a wide range of fusion and clustering algorithms
    • …
    corecore