1,566 research outputs found

    Korn, Harold L.

    Get PDF

    Korn, Harold L.

    Get PDF

    Geologic applications of thermal inertia image using HCMM data

    Get PDF
    The author has identified the following significant results. Comparison of a simulated HCMM image of the Pisgah Crater, California test site obtained from aircraft data with an image generated from the preliminary satellite data tape of the area indicates that the HCMM satellite data appears much as predicted by the simulation

    Temporal and dimensional effects in evolutionary graph theory

    Full text link
    The spread in time of a mutation through a population is studied analytically and computationally in fully-connected networks and on spatial lattices. The time, t_*, for a favourable mutation to dominate scales with population size N as N^{(D+1)/D} in D-dimensional hypercubic lattices and as N ln N in fully-connected graphs. It is shown that the surface of the interface between mutants and non-mutants is crucial in predicting the dynamics of the system. Network topology has a significant effect on the equilibrium fitness of a simple population model incorporating multiple mutations and sexual reproduction. Includes supplementary information.Comment: 6 pages, 4 figures Replaced after final round of peer revie

    On L2L^2 -functions with bounded spectrum

    Full text link
    We consider the class PW(Rn)PW(\mathbb R^n) of functions in L2(Rn)L^2(\mathbb R^n), whose Fourier transform has bounded support. We obtain a description of continuous maps φ:Rm→Rn\varphi : \mathbb R^m\rightarrow\mathbb R^n such that f∘φ∈PW(Rm)f\circ\varphi\in PW(\mathbb R^m) for every function f∈PW(Rn)f\in PW(\mathbb R^n). Only injective affine maps φ\varphi have this property

    Golden Sands Of Waikiki : Song

    Get PDF
    https://digitalcommons.library.umaine.edu/mmb-vp/1527/thumbnail.jp

    Multi-vehicle Control in a Strong Flowfield with Application to Hurricane Sampling

    Full text link
    A major obstacle to path-planning and formation-control algorithms in multi-vehicle systems are strong flows in which the ambient flow speed is greater than the vehicle speed relative to the flow. This challenge is espe-cially pertinent in the application of unmanned aircraft used for collecting targeted observations in a hurricane. The presence of such a flowfield may inhibit a vehicle from making forward progress relative to a ground-fixed frame, thus limiting the directions in which it can travel. Using a self-propelled particle model in which each particle moves at constant speed relative to the flow, this paper presents results for motion coordination in a strong, known flowfield. We present the particle model with respect to inertial and rotating reference frames and provide for each case a set of con-ditions on the flowfield that ensure trajectory feasibility. Results from the Lyapunov-based design of decentralized control algorithms are presented for circular, folium, and spirograph trajectories, which are selected for their potential use as hurricane sampling trajectories. The theoretical results are illustrated using numerical simulations in an idealized hurricane model. Nomenclature N Number of particles in the system k Particle index k = 1,..., N rk Position of k th particle with respect to inertial frame r̃k Position of k th particle with respect to rotating fram

    Conductance Phases in Aharonov-Bohm Ring Quantum Dots

    Full text link
    The regimes of growing phases (for electron numbers N~0-8) that pass into regions of self-returning phases (for N>8), found recently in quantum dot conductances by the Weizmann group are accounted for by an elementary Green function formalism, appropriate to an equi-spaced ladder structure (with at least three rungs) of electronic levels in the quantum dot. The key features of the theory are physically a dissipation rate that increases linearly with the level number (and tentatively linked to coupling to longitudinal optical phonons) and a set of Fano-like meta-stable levels, which disturb the unitarity, and mathematically the change over of the position of the complex transmission amplitude-zeros from the upper-half in the complex gap-voltage plane to the lower half of that plane. The two regimes are identified with (respectively) the Blaschke-term and the Kramers-Kronig integral term in the theory of complex variables.Comment: 20 pages, 4 figure
    • …
    corecore